So do I need to find a vacuum advance that can fit a Ford distributor that will advance timing less? If so, which one should I look for? Or is my next step to go up one size on the carburetor main gets?

what is your vacuum source for the vac advance, direct intake manifold or ported / timed vacuum?

square bore or spreadbore 4V intake, what carb?

It's a squarebore intake with a 600 CFM Holley Street Warrior on it with I believe #68 main jets. Carb is on a phenolic spacer to cut down on the gas smell after shutting off the engine.

Is there a chance the 4V intake runners to 2V head port mismatch could be making things a little lean due to turbulence?

and you're at 2800' ? that should make it near impossible to ping a combo that's not extremely out of whack, actually you can get away with an extremely out of whack combo that would knock like Orville Redenbacher near sea level. you're sure there's no vacuum leak / lean condition? is the carb heat circuit in the manifold carb pad drilled or is it unmachined / blocked / non-operational?

if you turn the vac pod screw inwards does that limit the amount of vac travel to less than 20* ?

I guess my next step then is to go from 68 to 70 on the main jets?

For the heat circuit on the carb pad, I'd have to pull the carb to look.

my thinking the adjuster affects load on a spring, making it more or less difficult for the vacuum to pull on? if you were to add tension to the spring in the can, your given amount of vacuum would be able to pull it less? being all the way loose the spring is at it's easiest position to be pulled on so you're getting the full travel. but anyway the 12* you're seeing is still workable for where i was going, to convert to direct manifold vac but you say it doesn't make a difference either way ATM, i'm thinking something else is going on that the vac adv can't affect

is this your carb give or take for the finish? they're showing a 66 jet in front

https://www.holley.com/products/fuel_systems/carburetors/street/parts/0-80457S" rel="nofollow - https://www.holley.com/products/fuel_systems/carburetors/street/parts/0-80457S

what do the plugs look like, do they need more color? are you familiar with the timing line on the ground strap?

https://www.motortrend.com/how-to/spark-plug-reading-101-dont-leave-hp-table/" rel="nofollow - https://www.motortrend.com/how-to/spark-plug-reading-101-dont-leave-hp-table/

That is indeed the carb I have. It came with 66 jets but I swapped them for 68 at some point a few years back. The plugs are mostly white with a little bit of tan at the bottom, and all 8 are pretty similar.

I just put the springs on last night. Before that, it had one "medium" and one "light" out of that kit.

I've been taking carb off and switching the jets as we post here, so I'll see how 70 jets do.

But also, I went to look into the thing about the carb pad, and found out it's actually aluminum and thus aftermarket. Grabbed a magnet and it won't stick to it (but it does stick to the steel valve cover). No brand name or numbers anywhere that I can find, but it looks like an Edelbrock 2750 from on top. I can say I feel like an idiot for all those times I said it was a 4V intake.

Would changing distributors possibly help me out? Maybe a hotter spark, better controlled, more adjustability, etc.? If so, which would people recommend?

how sure are you that your balancer inertia ring (and the timing scale) hasn't slipped?

i'd find 2 heavy Ford springs before swapping the entire dizzy. what's the rest of your ignition, is it Duraspark Hall / shutter effect electronic pick-up, any MSD 6A thing going on? asking because there's a possibility of polarity causing significant advance if reversed, and it depends if the box is analog or digital as to which polarity is correct. wire colors are often not matched for correct polarity even though that's the way they're set in the connectors from NIB

So the duraspark hall effect distributor is controlled by an unlabeled duraspark box with a blue wire strain relief, spliced directly into wiring instead of having the plugs that can plug in to make swapping a dead unit easy. No MSD box or anything like that. It has a stock-looking coil, but I can't see the labeling to tell if it requires a resistor.

The reason I was thinking of swapping distributors is because I found a Summit Racing ready-to-run distributor with the small diameter cap, which would get the springs to just below the rotor, saving time on getting it dialed in, and the vacuum advance adjustment adjusts the advance amount instead of the rate. It's designed to start advancing at 6 inches of vacuum and max out at 18 inches. The instructions say it's set at the factory to advance timing 5-7 crankshaft degrees at 15 inches. I can dial that back if I get pinging. It's getting hard to find a vacuum advance for the duraspark that will work for my needs -- the ones I find almost always don't say in the description how many degrees they advance, and most don't have a number stamped on the arm for me to double to find out the crankshaft degrees of advance. I only bought the one for a 1974 F100 with 390 because someone on one of the 429/460 forums said that one only advances by 12 degrees, and I was looking to step down from the 20 or more degrees I had before. Then I was thinking I could run the Pertronix Flamethrower coil I already have to get a more powerful spark since I wouldn't be running through a resistor wire anymore.

With the 2 heavy HEI springs, I get no pinging with the vacuum advance unhooked. But I want the vacuum advance because I struggle to get 12 mpg as it is, so I don't want to make my fuel economy worse.

I'm also considering doing the trick of dribbling water down the throat while revving the engine to steam clean out any carbon that might be in the cylinders. I've sprayed in SeaFoam before, but not the whole can. I don't know how much carbon might be in there from prior ownership, and I don't have a boroscope to look in through the spark plug holes.

I was looking around at distributor units, and I can get an Autoline rebuild of an original distributor for 335 and 385 series engines (D4006), which would be cheaper and would *hopefully* come curved close to my application. I don't suspect any issues with the duraspark control box because it starts and runs at any temperature (but I do carry a spare box just in case). I just don't know if I'd still have too much vacuum advance that way.

I still like the Summit one, but my hesitation is that if the module goes, I'd have to take the whole distributor apart to change it. I would like to buy a spare module in case I have to swap one on the side of the road, but having to pull the distributor, remove the gear, and pull out the shaft doesn't seem like a "roadside repair" to me.

The Pertronix distributors all seem to have a steel gear. I can't seem to find a definitive answer one way or the other whether the Pertronix gear will play nice with the gear on a factory cam. If it will, the "stock look" is available with the Ignitor I module, which appeals to me because I bought one of those earlier but never used it, so I already have a spare. But I can't find info on the adjustable vacuum advance. Their billet ones move the weights and springs up top, but only come with Ignitor II or III, so I'd have to buy another module if I want to have a spare. (And again with the steel gear.)

Jegs has a few nice looking house-brand distributors, but they don't give info about things like how much vacuum advance or how easy it is to swap a module, and their site doesn't make it as easy as Summit to find replacement parts to help me figure that stuff out myself.

I want to stay away from MSD because I've seen too many stories about quality going in the toilet but prices still being high.

There's a ProComp unit including a coil for $150, but I can't tell what material the gear is, I don't know about long-term reliability, and I can't tell if the vacuum advance is adjustable (I kind of doubt it because the vacuum hooks to the top of the canister instead of the front.) But ProComp is apparently Australian in origin, and I know Cleveland V8s were a big deal down under.

i'd be leery of the 'house brand' offerings being offshore and proprietary guts, but i haven't studied on them much yet. Pertronix in Fords just seems to always end up a PITA. there are new units out there that look like OEM but are completely different internally, IIRC they had some nice features but cheesy AF on others. not sure i'm a fan of those either. not long ago i was keen to get a genuine Aus Bosch unit because i like the flat mounting surface to use a GM module, mostly all i found was aftermarket / offshore copies and yes no telling what the vac pod is set up to do. can't a guy just get a decent Lightning Whirler?

FWIW i think the MSD's are Ford pattern as far as the pick-up modules and reluctors go so replacements are easy to find, and the distributor housings/ shafts / bearings are said to be pretty good stuff it's just their spark boxes that have earned the moniker Most Suddenly Die. and yes they're still proud of their work regardless of where it's done. an MSD Whirler can run your existing Dura-module or they have Ready To Run's with i'm guessing a GM module inside?

Thoughts?

Also, I went and got an inspection camera so I can pull the plugs and look for carbon deposits in the combustion chambers.

I looked in two of the cylinders with the new camera, and there's just a little bit of carbon in a few spots. Otherwise, I can even see the concentric ring design on the flat-top pistons. I unfortunately can't get the angle to look at the combustion chambers to judge their condition, but I don't think carbon deposits are raising my compression ratio.

I'm 99% sure the engine had never been apart before I got it, except to install the aluminum 4-barrel intake, replace the timing chain with a double roller, and put in the Duraspark. (I found pieces of the nylon timing set in the oil pan when I went to change the rear main seal.) I'd be extremely surprised if the cam that's in it now isn't the one that it left the assembly line with.

Given the hackjobs on this car I've found, I'd almost want to verify the prior owner didn't install the camshaft gear to the 4-degree retarded position or something, except I don't feel like removing all the accessories if the water pump isn't leaking. But side question: could futzing with how advanced or retarded the cam is make an engine want less timing? I thought Clevelands were supposed to want lots of timing early, but mine seems like the opposite of that.

As for fuel, premium in California is 91 octane. I'd been running that exclusively until very recently because I figured the 2V used regular fuel when it was new. It was after I put in 87-octane that I noticed the noise went away when I'd give it more or less throttle, but it had been making the noise for a long time before that. I thought it was the speedometer cable (the speedo needle does shake a little bit up to 20-30 mph). I used up half a tank so I could put premium back in, and put 10 gallons of it into my 20-gallon tank to make 89 octane (half 87, half 91). It made no difference.

Here is a picture of the wiring for the Duraspark box. The power wires are connected to the + and - terminals at the coil, and come in through that blue wire conduit you can see a tiny bit of at the edge of the photo. The red and white wires come from the box, are spliced into black wires, and run to a plug. It looks like the white-then-black wire just isn't plugged into anything, so I think the timing retard at start just never happened. I don't know what to make of the other four wires coming out of the module, other than that you can see where two wires are spliced into the phone cable and head toward the distributor.

i thought i had more schematics but this should do for a start pun intended. red & White are Ign switch IDK why Dude has them on the coil or why it works like that? if the White is not connected you should have no spark during crank but it's getting power during crank from the Re wire off the coil

So as hacked together as this is, other than not getting retard at start, my only worries are voltage drop between the distributor and the box due to a long run of thin wire, and having too little voltage at the box because it's being fed through the resistor wire, which I'd think would have ruined the box. I believe the resistor wire is still there because the 1972 yellow-top coil would have burned out if it were fed the entire 12V full-time for this long.

But once the new distributor shows up, I'll use the resistor wire to trigger a relay, remove this other stuff to clean up the engine bay, and hopefully enjoy good timing and a hotter spark from the 40,000V coil.

This is exactly what I was going to suggest.  I'd scrap that mess and start from scratch.  Running the relay you can get a clean 12 volts to the ignition.  I have used the setup on both my ignitions, first with the Pertonix and now with my Duaspark/HEI hybrid. 

And yes, a 1972 would have a resistor wire because the coil and points needed to run on the lower voltage.  Only when the ignition switch was in "start" did it get the full 12 volts.

this might be what i was looking for, Duraspark 101, retrofit schematics inside

https://pantera.infopop.cc/topic/parts-needed-to-convert-duraspark" rel="nofollow - https://pantera.infopop.cc/topic/parts-needed-to-convert-duraspark

George says somewhere in the link in the above post that some resistance is needed 

here's more info ...

https://pantera.infopop.cc/topic/duraspark-ignition-question" rel="nofollow - https://pantera.infopop.cc/topic/duraspark-ignition-question

But it looks like by switching to the Pertronix Flamethrower coil, I'll get the benefit of the hotter spark that the red Duraspark I setup provides.

So I got the new distributor in, and unfortunately, it's the newer style where you stick a hex wrench into it to adjust it instead of the kind with shims and a spring. But I got the distributor installed and the Pertronix wired up, and found the vacuum advance only pulls 8 degrees of advance when I apply vacuum with the Mitivac. (New distributor has 13 and 18 weights, set to 13, so 26 degrees of mechanical advance.)

So even with the vacuum advance turned 10 turns out to have advance late, and base timing set to just 8 degrees, I still get the ping at cruise. A little bit with vacuum advance disconnected, and mote with vacuum advance. Kind of annoying since with the new distributor, the probably factory original style of curve, the hotter Flamethrower coil, etc., it feels stronger now with 8 degrees of base timing than it did before with the hack-job Duraspark even with 12 degrees of base timing.

BUT... I tried checking for vacuum leaks again. I had sprayed around before and didn't find anything, but this time, I was more specific and sprayed brake cleaner on top of where each intake runner attaches to the head, and I found that when I spray the intake-head union right over there the exhaust crossover would have been, my idle drops by 40-50 RPM. It does it more on the driver's side than the passenger's side. So now I'm thinking I've had an intake vacuum leak all this time and am going lean on some of the cylinders. Looks like time to order new intake gaskets. Hopefully I can then advance the base timing to 10-12 degrees and enjoy the power.

Edited to add: I got the idea to try retorquing the intake bolts to the spec in the 1972 shop manual. I went with 30 ft-lb for the larger bolts and 24 for the smaller ones. All the bolts tightened up at least some before getting to spec. Two weren't much more than hand tight, and another one was straight up loose. I'll take it for a drive either this afternoon or tonight and see if things improve before I buy a new gasket set. 

So today I bent back the tab on what looks like the heavier of the two advance springs (from what I can see through the hole in the breaker plate) and I'll see if that helps tonight. If not, the next step is to build a bushing for the advance weight stop pin by building up layers of heat shrink tubing to limit total mechanical advance.

Oddly enough, I seem to get the most power (quickest 0-60 time  on a nearby back road) with base timing at 6-8 degrees. We'll see how tightening the spring to make advance come later changes that. Also, I still get pinging (albeit less) with the vacuum advance unplugged. New vacuum advance only advances it by 8 degrees, and I have it set to come in as late as it'll let me.

I got out the timing light, and I'm still at 6 degrees btdc initial. I grabbed a heavy tool box to hold down the throttle, and found that my mechanical advance after bending the tab is such that it's only at 12 degrees btdc at 1,500 rpm, which is the rpm where it's doing 40 mph in top gear. Even if the vacuum advance is adding its full 8 degrees, I'd only be at 20 degrees btdc at 1,500 rpm at cruise. Surely it shouldn't be pinging in one cylinder at just 20 degrees at 1,500 rpm, should it?

Is there anything else that could make a loud tick noise at cruise between 40 mph and 50-55 or so (maybe higher, but road and wind noise gets too loud), which is 1,500 to 2,000 rpm, when vacuum is about 15 inches or so on the gauge, but goes away when I give it more throttle OR less throttle?  Speedometer cable? I did one drive where I hadn't hooked it back up correctly after changing the instrument cluster bulbs to LED, and I could hear the cable end spinning against the back of the speedometer hookup, but also heard the ticking noise separately when I was doing 40 as indicated by my phone's GPS speedometer app. Exhaust leak? I'd think that would get louder when I give it more throttle.

I do have a vibration when it revs between 1,500 and 2,000 in park or neutral but that I don't feel when driving at those RPMs in any gear. I think that might be the torque converter. I don't remember that vibration happening before I pulled the transmission to change the front input seal and pump gasket. Can I remove the nuts and push the converter back far enough to turn it 180 degrees and reinstall the nuts without having to unbolt the transmission from the engine? I did try removing the nuts and reinstalling them by torquing them in a criss-cross pattern rather than in a circular pattern to ensure it was straight. But could this vibration also be the source of my noise? Seems weird that it would instantly stop making the noise with any change in throttle.

I did order a new intake gasket set and it'll be in tomorrow morning (Friday), but I don't think the weather will let me install it this weekend. Other than changing that, I'm not sure what else to do.

I was going to suggest to use a piston stop to check TDC is correct on your balancer, but based on your latest post maybe it is not ignition ping?  When did the ping start?  Was it around the same time as the vibration?  Do you get the noise under load only or will it make it when revving in neutral?

The speedometer cable can make a noise, but it usually sounds like it's coming from inside the car, not the engine.  I would also agree that exhaust leaks generally get louder with more throttle, and sometimes go away with some heat in the engine.  If you have exhaust manifolds, they do crack, in particular the passenger side.  I don't think the convertor would be the issue, unless it was bad/out of balance and reorienting it likely wouldn't fix that.  You could unbolt the converter and try firing up the engine to see if it still has the vibration.

Can you do a video so we can hear the sound too? 

On the intake, if you do have port mismatch, I am not sure how great of a seal you will get with the gaskets.  That could be part of the vacuum leak issue.  15 inches seems a little lower than what I would expect for a stock 351C 2-V engine at low RPM. 

I don't really notice the noise in neutral. Maybe a few taps here and there, but nothing like when it's on the road.

So I was searching up the symptoms last night, and apparently some guys on a Subaru forum had similar and it turned out to be the rod bearings. Is that a possibility here too?

I uploaded an unlisted youtube video where the noise actually comes through:

https://youtube.com/shorts/vCoVoQP-I18?si=RyRhYNmJW6L11ulh" rel="nofollow - https://youtube.com/shorts/vCoVoQP-I18?si=RyRhYNmJW6L11ulh

Inkara1 wrote: ... I verified TDC by rotating it until the pointer was at 0, then stuck a camera in the No.1 cylinder spark plug hole. It's either right on or extremely close. ...

The TDC is the one for #1 cylinder on its compression stroke. Put your finger over the hole as it approaches TDC, if it doesn't blow your finger out then it's on the exhaust stroke(the exhaust valve is open at that time).

So I think I have an idea to determine if I'm getting a little rod knock. I think I'll pour in a quart of Lucas oil stabilizer. If the noise goes away, I know it's time to do bearings. If the noise doesn't go away, then I'll just change the oil to get the Lucas back out of it (it's probably due for a change anyway) and keep searching for my cause.

I can get a set of rod bearings for like $9. I already have main bearings because of where I replaced the thrust bearing, so the rest of the main bearings are still in the box ready to install. I figure the Lucas is relatively cheap enough that I can do this test without having to take the time to do the work to change out the bearings until I know that's the actual issue.

So I'm happy I don't need to go through the work of changing the bearings, but sad that I'm no closer to finding the issue.

On a C6 transmission, can I get the converter pushed back far enough to be able to run the engine without it hooked up without having to unbolt the bellhousing from the engine?

When I changed the valve seals, I torqued the rocker arms to the head to shop manual spec (non-adjustable). I did so after I did each cylinder, so the torquing was always done with the valves not being opened. I have a leaking rubber valve cover gasket, so I need to swap the gaskets anyway, so I guess I could retorque the rocker arms while the covers are off. Anything special to torquing them? Is it best to torque with the valves at rest or with them opened?

For inspecting the flexplate, do I just remove the converter nuts, push it back as far as I can, and then shove the inspection camera up there? (It looks like a stock converter, with studs and nuts.)

and i'll throw this out there, my winter daily salt eater has what i believe to be an extremely broken flex plate. it makes a of a racket that i suppose could be on a lesser scale mistaken for ignition ping? as it is it sounds as if the engine identifies as a diesel and who am i to question that? it sounds like it's ready to kick out a rod but shows good oil pressure and goes down the road 80mph playing it's beat. fine with me, keep rollin baby, eat that salt! keeps my summer daily from having to chew on it

if the flex is cracked up near around the crank bolt circle you might still get a glean on it through the inspection cover with a flashlight?

retorquing the nonadjustable rocker arms won't change anything but if you're game have a look at how much preload is on your lifter plungers. as you described go through the firing order each cylinder at a time with the lifters on the cam base circle. i really need to find out for myself where that is but until then i guess TDC on the compression stroke is generally accepted? so loosen the 2 rockers on the cylinder that is in TDC firing position (chalk the balancer for each 90*ish) and now it's time to get a feel for what is called Zero Lash. this is when the rocker is just snug enough that any more tightening of the bolt will begin to depress or preload the lifter plunger, send a couple minutes getting the feel, just the bare socket or even no socket just your fingers turning the rocker bolt and your other hand your fingers slightly rotating the pushrod back & forth. snug the bolt and you'll feel a miniscule drag on the pushrod, that point is zero lash. paint pen or chalk mark the bolt on 1 side your choice top bottom whatever so you can count how much revolution the bolt turns from zero lash to bottom tight. maybe not necessary to go to TQ spec but snug hard enough that the bolt has effectively stopped turning. the distance from Zero Lash to bottom tight is your lifter plunger preload. bolt rotation can be converted to decimal fractions of an inch by using the thread pitch of the bolt and a little math. IIRC the bolt is 5/16-18 so 18 threads (revolutions) per inch. 1 / 18 =  .055" per 1 full revolution of the bolt. if the bolt turned 1/2 a turn from Zero Lash to bottom tight your LPP is .0275" give or take because of the rocker ratio and i've never sat down and figured out how that affects the deal. document each rocker and you can shim the pedestal to equalize your preload. shim kits are available or you can use almost any metal to make your own, some guys even use brass and that gets criticized but i guess it works. sandwiched between the pedestal and the head it doesn't take abuse
https://www.summitracing.com/parts/fms-m-6529-a302/make/ford" rel="nofollow -
https://www.summitracing.com/parts/fms-m-6529-a302/make/ford

Would flat-top pistons be stock for a 1972 2V engine? Mine look exactly like the one in this ebay listing:  https://www.ebay.com/itm/166319298175?chn=ps&_trkparms=ispr%3D1&amdata=enc%3A1LwXORTiyQ2GdVHpKSB8QPQ24&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mkscid=101&itemid=166319298175&targetid=1644837435963&device=c&mktype=pla&googleloc=9031792&poi=&campaignid=20125739985&mkgroupid=149128855676&rlsatarget=pla-1644837435963&abcId=9312975&merchantid=6336834&gad_source=1&gclid=CjwKCAiAuYuvBhApEiwAzq_YiZJ-QgwFOhf-npTmC-QuUkZOPdhKltQHrW9dn-ok_9LzhDcgT3-XNBoCus0QAvD_BwE" rel="nofollow - https://www.ebay.com/itm/166319298175?chn=ps&_trkparms=ispr%3D1&amdata=enc%3A1LwXORTiyQ2GdVHpKSB8QPQ24&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mkscid=101&itemid=166319298175&targetid=1644837435963&device=c&mktype=pla&googleloc=9031792&poi=&campaignid=20125739985&mkgroupid=149128855676&rlsatarget=pla-1644837435963&abcId=9312975&merchantid=6336834&gad_source=1&gclid=CjwKCAiAuYuvBhApEiwAzq_YiZJ-QgwFOhf-npTmC-QuUkZOPdhKltQHrW9dn-ok_9LzhDcgT3-XNBoCus0QAvD_BwE

Also, I can verify my heads aren't Australian 302C. The numbers on the top corners appear to have been ground off, but the dot is still there. What's left of the base of the number looks like it's probably a 2. Plus, the exhaust manifolds have a part number that returns to a 2V setup. My understanding is that you can get a 4V intake to seal against 2V heads, but absolutely cannot get a 4V exhaust to seal. 

so the end head bolt bosses are round at the top? IDK what the Aus heads did for the 2 & the dot

yes all 1972 engines came with the same flat top pistons. today's calculation a 72 2V should make 8.6:1 static squeeze, it would take a Very small cam to make trouble from there

https://youtu.be/h8RrW1xLeoY?si=o0D8dDjf2RzwXHsa" rel="nofollow - https://youtu.be/h8RrW1xLeoY?si=o0D8dDjf2RzwXHsa

I also verified that I have a C4 flexplate with the C6 transmission. I pulled the starter to put the camera in there, and while I had it that way, I stuck a finger in there and felt the offset the C4 flexplate has. As far as I've been able to find, the flat part of the C4 plate is nearly 1/4-inch closer to the engine block and the converters are sized along with that. Using a C4 transmission with a C6 plate will bolt up and work, but will press against the trans pump insides and press the crankshaft against the thrust bearing. But I have the opposite mismatch: C6 transmission with C4 flexplate. I can't find any info on whether that would damage anything, or whether the converter would just engage the pump a little less. I know my pump works because the trans shifts and I have a temperature gauge on the trans fluid, which heats up and cools down depending on situation. 

So does it look like it's worth buying a new flexplate? Would it be worth changing the converter too? 

I plan to install them on Saturday. I got a couple of 24-inch 7/16-14 threaded rods, so I figure I'll put those in place of the bottom two bellhousing bolts, then just pull the trans back as far as I can get it with the jack still jacked up. I hope that's far enough to swap the converters so then I don't have to undo the exhaust or the parking brake cable, thus saving lots of time. Then the threaded rods will help align it back into place.

I really hope it gets rid of the noise and the 1500-2000 RPM shake in park.

The new converter has bolts instead of nuts, so I could check if the vibration goes away with it disconnected. But I'm wondering now if this is caused by my crankshaft that has outrageous end play because the thrust bearing wore a groove into the crank as deep as the bearing itself. Either that or check the valvetrain to make sure everything is torqued to spec.

That thrust bearing and the crank end play are the biggest worries. That is usually created by a mismatched torque converter, or improper install of the TC, not into the pump all the way.

Look at the old oil carefully, cut open the filter and see how much metal is in it. Usually with big end play, the engine has to come out and be rebuilt due to the bearing and crank wear.

The torque converter should move freely when the nuts are not on, back and forth. The crank should move a little too, but just a hair, the thrust spec is likely around .006 as a guess, if it's 1/4" then it's bad.

crankshaft free end play is called out at .004" - .010" in the factory shop manual

The car originally had a C4 in it but got switched to a C6 at some point (with the C4 flexplate). I wonder if something happened to the C4 that made the converter swell.

When I pulled the oil pan to change the rear main seal, I found the chunks of bearing foil from the thrust bearing in the pan. I swapped the thrust bearing out for a new one so I'd at least have some bearing material in hopes to keep the crank from rubbing the block. I had been worried that the damage was something I did, but I still had the oil filter that was on the car when I got it, so I cut it open and found bits of bearing in there. It definitely needs a new crank, but I drove it ~500 miles last October, and it used barely any oil, so it seems like the rings are good. But with the trashed crank, I didn't want to put in the time/money to replace all the bearings.

The idle is a little bit shaky in park/neutral. I bought a compression tester but hadn't gotten around to using it yet. But the power feels fine, so it seems like I'm running on all eight cylinders.

it's amazing what will run fairly well but when you get your peepers on it you're like How The did that work?

from what you say about the excessive crank free play nothing good can happen from this point if you keep running it

My main worry is that the Fairlane Club shows I go to can be pretty far away. It's a six-hour drive to the new Nor-Cal meet in May, and then the one I'm hosting in October in the LA area is 2.5-3 hours away. I just want to be reasonably sure the bottom end won't explode on the freeway hours away from home.

Also, could replacing the engine and transmission mounts help with the shake between 1,500 and 2,000 RPM in park/neutral? I haven't gotten a good look at the rubber on the motor mounts. The rubber on the trans mount *looks* OK, but I also don't know what I might be searching for on that.

I am wondering I the previous owners swapping of transmissions buggered up the crank. I know you said the c4 flex has clearance, but maybe there was a combo in there that put too much pressure on the crank. It sounds like who ever owned your car before really cobbled things together, and now you are cleaning up his mess.

I think the engine needs to be pulled and a deeper dive inside it needs to happen. Maybe a used 351 is a good alternative. Or even a 400 or 460 if you can find a donor car. Any midzied 70s full frame Ford or Tbrid and Lincoln Mark IV and V can supply what you need for a swap.

The manifold connections can be helped with a normal other application donut seal. People often get them from any parts store that can show their variety of sizes.

I would take the engine back apart soon, that crank wear is too much, it won't run like that for long before it creates more damage.

The thing with engines from private sellers is not knowing if they're hiding the same issues (whether known or unknown to the seller). Or there's a fully rebuilt 351C-2V on eBay from "Five Star Engine Exchange" out of Arizona for $5,995 with free shipping if paying that price. Only thing is they don't say if the valves have been replaced (just that the heads have been completely remanufactured including new guides and seals and performance 3-angle valve job). So almost $6K, which I think I'd struggle to get the OK from the wife on. There's also a 351C-2V long block from Mabbco out of Texas for $2,839.98 plus $525 shipping, but same question about the valves.

Are you planning on pulling the engine?  I think you got to tear into it and see what is going on before you decide what the best course of action is.  Maybe the used crank will work ok, but I'd want to find out what is going on in the lower end first before just dropping a new crank and bearings in.  If the rings and cylinders are good, you might be able to get away with the new crank and bearings.  I don't think a balancing is mandatory if you are just replacing a stock crank with another, but Rockatansky can probably speak to that. 

If you do go with a long block or a short block, you could always swap the valves yourself if you are concerned about the 2-piece valves. It's not hard to change the valves if you have the heads off.  Of course this can turn into a pretty deep rabbit hole the more you dig into this engine. 

For sure, I assumed you were going to pull the engine to change the crank.  I just didn't know if you planned to pull the engine at all, as I knew you were still bouncing around some different ideas.  For the engine stand and crane, you can probably rent them.  Or check marketplace/CL and see if you can find used ones at reasonable prices, then resell when done the job so you don't have to store them.

I am sure Rokatansky will chime in with some additional advice.  Good luck and keep us posted on the progress. It sucks that you have to go through this job, but maybe tearing into the engine and giving it a once over is a good idea to ensure it's up to the task of long distance towing.

The used crank should be okay. I'd be more concerned about what ither damage has been done because of the glittler. Hopefully the filter caught it all.

Keep your stock cam and lifters. If they are in spec and in good shape, I'd leave them alone. I agree...the "new" stuff out there is questionable. 

Reusing very old stock pistons isn't a very good idea. Not many factory pistons are worth keeping, not counting super rare low mileage examples. I've rebuilt two 302 HO's using the old pistons, one whole set was fine(112k miles), and the other had one cracked piston(137k miles). The cylinders were still fine and they used no oil before rebuilding. But those were OEM forged pistons, which was uncommon in any Fords.

I'd be most concerned about the cost and machine work for a different crank, and the pistons etc.The valves of course you want to replace if possible, high rpm's caused most of those failures.

Pistons seem to cost way more than the old days, cheap end stuff can be $400 a set, while nice forged pistons are more like $600+. New pistons should mean balancing the assembly again.

Cost go up fast. $6k for a rebuilt stock level 351C is crazy. I can do that for $3k easily, they are overcharging for both the core parts, and the machine work etc. The refresh I'm planning for my 4V will be $1100ish for the roller cam upgrade, the heads may be under $400, but maybe $750 depending on the valves and wear. Mine may not need balancing or cylinder work, if it does then that's another $500. The oiling system to hit 5500 may be nothing it it's already done, plus depending on what shift rpm(5500 or 6500), could be another $400-$900(roller rockers).

But if I put in a new (refurbished) crank, am I likely to be able to get away with it for a few years until time and budget allow for a full and proper rebuild?

The crank I found for $250 is pictured wrapped in plastic and is marked as being ground 20 under for the mains and the rods, so it appears the machine work is done. The hope is to have the car running again by mid-May to drive 6 hours to a Fairlane Club show, and I'm concerned that if I get a short block for $2K, the lead time will be too long (plus I'd assume I'd want to have heads gone through, valve guides replaced, in addition to aftermarket valves, etc.). Where I live is rather isolated, so machine work isn't exactly convenient out here.

Maybe - that is the big question. I think until you get it apart to examine the bottom end it will be hard to say for sure.  Hopefully nothing else is damaged.  Replacing only the crank and bearings is something we would have done back when I worked at a dealership garage.  We wouldn't rebuild an entire engine for one bad component. Often times it worked out, so if you go that route maybe it would for you too.  It sounds like the rest of your engine is in decent shape.

The rebuilt crank is a possibility, but the risk is the machine work done to it. If they did not alter the stock balance of it during the machining process, then it should bolt in if the machine work was really good. If they didn't work it just right, the actual bearing clearances might be off a little, or the balance not quite right.

Take it apart first if you can, to get a good idea of what needs help now and what looks okay.

the thought of a new production flat tappet cam & lifters is absolutely cringeable and understandable to not want to go there at all. and rollers aren't cheap. stick with / hold on to / reuse the current possibly 50 year old cam? i'm still on the SS Cringe. even if it's technically still good "ran well when pulled" how much time does it have left in it and will it survive being uprooted & replanted? i say uprooted & replanted because Me, if i'm pulling the donk and swapping the crank, i'm going to take it all the way down and minimum berrybush hone & ring it. rings bearings timing set that's my minimum if it's coming out. 1 washer shim on the original oil pump, freeze plugs, RTV & a nice thick coat of Ford Dark Blue. the heads are a problem, why do the crank if you're gonna let a valve drop & destroy it all? cheapest decent stainless valves, retainers & locks (because single groove vs multi groove) and a bargain valve job. i know it's starting to add up. and the damn cam. i'm still seeing older production NOS cams up for sale, lifters are a problem too. there's a Craigslist ad near me for lightweight Ford race lifters i might check out, the ad's been running forever. another idea'r popped up, Rhoads lifters may still have some quality / control going on IDK? 

i keep coming back to a saying from a wise man, "At The End Of The Day Ya Gotta Piss With The Ya Got"

and the con rod nuts. not the bolts, just the nuts, because the threads fracture out causing a failure that always gets blamed on the con rod bolts. the bolts are decent, the nuts are gahbage. cheap insurance that makes it easy to sleep at night, like the valves. why they don't sell a 16 pack IDK, maybe they do now?

check Advance Auto and any others near you for a crank kit, Advance shows a kit but won't commit to fitting a Cleveland. $332 / 50 core IIRC eliminates risk of buying gahbage from a scammer online

https://shop.advanceautoparts.com/p/crankshaft-rebuilders-remanufactured-crankshaft-kit-15590/5950481-P" rel="nofollow -

https://shop.advanceautoparts.com/p/crankshaft-rebuilders-remanufactured-crankshaft-kit-15590/5950481-P" rel="nofollow - https://shop.advanceautoparts.com/p/crankshaft-rebuilders-remanufactured-crankshaft-kit-15590/5950481-P

 

I'm driving to Bakersfield tomorrow to meet with a guy who has a bunch of different Ford cranks to see if there's a Cleveland crank, hopefully already ground. But I do have a machine shop in my town that's well reviewed, so I should be OK there.

I assume the heads are a lot easier to remove from the engine if it's out of the car. Are the "stock replacement" valves from Enginetech, Melling, etc. one-piece? To get stainless valves with single-groove keepers means spending like $400 on valves plus new keepers. The "stock replacement" ones would reuse the old keepers. All I'm looking for is to be as sure as I can that a valve head won't drop off, and if I can do that for $55 for valves and like $40 for gaskets, I'd like to do that and save up for a new short block, aluminum heads, a roller cam with the retrofit roller lifters (Howard's and Melling offer those), etc. I'd be looking at like $6K for that, so if I can under $500 now and be as sure as I can reasonably be that I won't have my bottom end explode on the freeway until I have the budget for the all new engine, that's really attractive. 

My rear main bearing is in the photo below. The main surface of the center bearing was a lot better, but the thrust surface was gone. I didn't remove the other three bearing caps to look at those. I only replaced the center bearing so I'd at least have some thrust surface. So I'm guessing the glitter in the oil is from this. The oil pump is new (I accidentally screwed up mounting the old one, so the drive shaft was pushing against it and it broke the pump neck, so I got a new Melling pump and shaft).

any stock replacement and even some performance valves are 2 piece friction welded. Qualcast is an entry level brand that Tim Meyer and Alex's Parts have carried, Goodson currently lists them so that says something to their quality. they have your intakes available but the X's are out of stock ATM

Qualcast on ebay w/hardware, not sure if the retainers are right for your springs though

https://www.ebay.com/itm/276281197029?itmmeta=01HS4PXCBHH0Z3NK3XJEYFQZ6E&hash=item4053a481e5:g:9NIAAOSwW3llodqN&itmprp=enc%3AAQAJAAAA0FFn8fRRVHIu91%2BvzPHGBCavKupSM2u1CtLE5KUm8kmpkUKTdIMM0mUAu5EAT95xcqH3%2FH6EwF37SFpmmqtUBvZ2pp3R5IOqUDJhHFb79UV1CAKBAv1Yu8c4crEv7EL8IcW2A2SnmwTB9wXTbpgdVAAC9DMHk6Mp7LO%2B7o5q%2BeW5R7yQZF1TUcPli7GNJIkMlM%2Fg9z0P2g9MHxj70v6aWIW1Nhb39dnusiZLbSL3nB5iAj%2BtF%2B84NE7lbgilLs3CRuT75S5PU9GafvhAImu5DEk%3D%7Ctkp%3ABk9SR_rF9ZbJYw" rel="nofollow - https://www.ebay.com/itm/276281197029?itmmeta=01HS4PXCBHH0Z3NK3XJEYFQZ6E&hash=item4053a481e5:g:9NIAAOSwW3llodqN&itmprp=enc%3AAQAJAAAA0FFn8fRRVHIu91%2BvzPHGBCavKupSM2u1CtLE5KUm8kmpkUKTdIMM0mUAu5EAT95xcqH3%2FH6EwF37SFpmmqtUBvZ2pp3R5IOqUDJhHFb79UV1CAKBAv1Yu8c4crEv7EL8IcW2A2SnmwTB9wXTbpgdVAAC9DMHk6Mp7LO%2B7o5q%2BeW5R7yQZF1TUcPli7GNJIkMlM%2Fg9z0P2g9MHxj70v6aWIW1Nhb39dnusiZLbSL3nB5iAj%2BtF%2B84NE7lbgilLs3CRuT75S5PU9GafvhAImu5DEk%3D%7Ctkp%3ABk9SR_rF9ZbJYw

or step up to Ferrea

https://www.ebay.com/itm/332058372784?epid=1437442197&itmmeta=01HS4PXCBHZ45P2P8V2YEFGQD9&hash=item4d5038aab0:g:TGAAAOSwX6VTyX8k&itmprp=enc%3AAQAJAAAA8E6REtgWZVTkkc%2Bhgjfdp73YcgkWe7nx1Of9%2B%2FYiDi3as0ICaoBrNGcMjXnbytp%2FK8Lgkt9DjqDp7KQyflRHvJ%2BtyrGtTx28xVGuY1R%2Bz%2BxBh70KKMLbEZ0rk0ACAzmEX7tbZN%2FIPUBkkqxSBrVq8SFyJAwSnem%2BdF2FjaQscWqQjvLdldE1CBlsxIHuKmZYX8kov%2BzBrF2UgV2B4CMrcs1iDLErHkVuiDfjr1HJFrR9VmySu4LUNnapwBuW2px13WmYA14LiCtI09WMIDBcCeEhtj9g5xMst8swJNqUyLEkRNaIiNE%2FoQTBdbI2mPZgng%3D%3D%7Ctkp%3ABk9SR_rF9ZbJYw" rel="nofollow - https://www.ebay.com/itm/332058372784?epid=1437442197&itmmeta=01HS4PXCBHZ45P2P8V2YEFGQD9&hash=item4d5038aab0:g:TGAAAOSwX6VTyX8k&itmprp=enc%3AAQAJAAAA8E6REtgWZVTkkc%2Bhgjfdp73YcgkWe7nx1Of9%2B%2FYiDi3as0ICaoBrNGcMjXnbytp%2FK8Lgkt9DjqDp7KQyflRHvJ%2BtyrGtTx28xVGuY1R%2Bz%2BxBh70KKMLbEZ0rk0ACAzmEX7tbZN%2FIPUBkkqxSBrVq8SFyJAwSnem%2BdF2FjaQscWqQjvLdldE1CBlsxIHuKmZYX8kov%2BzBrF2UgV2B4CMrcs1iDLErHkVuiDfjr1HJFrR9VmySu4LUNnapwBuW2px13WmYA14LiCtI09WMIDBcCeEhtj9g5xMst8swJNqUyLEkRNaIiNE%2FoQTBdbI2mPZgng%3D%3D%7Ctkp%3ABk9SR_rF9ZbJYw

FWIW all Cleveland cranks are '4M' cast code, some are 4MA, 4MAB all the same as far as interchangeability. nobody knows what the engineering changes were

4: 132 □ 8: 128

3: 110 □ 7: 117

2: 124 □ 6: 130

1: 147 □ 5: 137

There is a good bit more carbon on top of the pistons in cylinders 3 and 7.

Then I put a little leftover oil into cylinder 3, and instead of 110 psi, I got 140.

So I think I need to tell the crankshaft guy I shouldn't go over there until some decisions get made, since my understanding is that if oil makes the compression jump by that much, it's the rings. I'm surprised I'm not getting blowby or oil consumption.

...or since there's carbon on those two pistons, might the water down the carb trick loosen the compression rings?

I'm thinking the block would need work because of this (also cylinder 3):

Just my 2 cents worth

Rock Auto actually has the Qualcast valves. The single-groove is stock for 1977-up 400s, or they have Qualcast multi-groove available as well. I'll just get the single-groove valves for a 1979 Bronco with 400.

Can I just leave the cam in and not worry about the cam bearings?

Its sounds like you got a decent deal on the crank.  Like I said, I am not expert, but if I were in your situation, I'd take a chance and leave the cam and lifters and cam bearings as is.   Like 78FordLTD2 says, do a freshen up as best as you can and hope it stays together until you can do a proper build. 

I forgot to ask, when you did the torque converter earlier, did you idea to move the trans back with threaded rod work?  Or did you just end up dropping it?

I ended up having to drop it. The exhaust got in the way of the part of the bellhousing that sticks out to hold the starter, and if not for that, I think I would have had enough room for the body of the converter but not also the snout that goes into the trans to make it out. But I was able to drop it enough to get the converter out without having to undo the exhaust other than from the manifolds and without having to undo the parking brake cables, so that saved a lot of time. I cut one of the threaded rods to make basically a longer bolt to help line up the trans to make it easier to put on. Plus, the Hughes converter uses bolts instead of studs/nuts, which is nice because I didn't have to worry about the converter being lined up with the flexplate bolt holes.

The guy I bought the crank from said someone else had recently bought a bunch of other Cleveland stuff, so I think the pickings were slim. So he polished the rod and main journals, but the sides by the main where the thrust bearing would be against didn't get polished. Do I need to try to polish those two areas so the new thrust bearing doesn't wear out quickly?

So last night I dribbled some water down the carb to steam clean the carbon. I didn't really see the ugly black smoke I thought I would, but today I looked at the twomost carboned pistons and they're not fully clean but a lot better than they were before. I can see the concentric circles on the piston top through the black now. The idea was to also see if it would free up the rings. I ran the compression test again. The engine was cold but only sitting one day instead of a week. This time I got these numbers:

4: 135 □ 8: 130

3: 125 □ 7: 125

2: 128 □ 6: 135

1: 140 □ 5: 143

I'm kind of on the fence about whether to rering the pistons because I was hoping to save some work somewhere, but also, I did order new rings with all the other stuff. Should be here in various shipments between Thursday and Monday. Fortunately, I work from home, so that protects against porch pirates.

Oh, I guess my other question is if my valve springs are OK to reuse. Rock Auto didn't have 16 springs of any one single brand for the 2V head. I assume it can't be good to mix brands since different manufacturers might have slightly different spring rates.

You can re-use the valve springs as long as they are in service spec. Measure their hieight and test the strengrh of the spring using a valve spring tester. Some guys don't like using the old springs and will swap them out with new ones but I don't see anything wrong with using anything that is still in spec.

I don't think your cam bearing will be an issue. To you would feel better changing them, then by all means replace them. Easier to do it now than later. The same with your rings. Was it burning a lot of oil before?

If thus is basically a stock rebuild, you should be okay.

the springs will be subject to how the new valves and retainers set up for installed height, and what their pressure is at that installed height. new retainers are required because the stock multi-groove retainers are more like / if not actually  for 3/8" stem valves vs 11/32". the multi-groove locks take up the difference between the 3/8" retainers and the 11/32" valve stems. the springs also need to be checked for clearance at max lift / coil bind height. Surprise! Surprise! Surprise!, Alex has drop in spring kits listed 30 days out

https://alexsparts.com/ford-351-cleveland-valve-spring-kit-drop-in-fit-351c-w-hyd-flat-tappet-custom-built-ships-around-30-days-after-ordering/" rel="nofollow - https://alexsparts.com/ford-351-cleveland-valve-spring-kit-drop-in-fit-351c-w-hyd-flat-tappet-custom-built-ships-around-30-days-after-ordering/

Are the threads in an aluminum intake strong enough that I can put a plate on the carb mount and lift the engine that way? Or do I need to find mounting points elsewhere to lift it? I don't have the lift points that I've seen on the exhaust manifold bolts on some other engines.

is this the thread?

https://www.speed-talk.com/forum/viewtopic.php?t=49112" rel="nofollow - https://www.speed-talk.com/forum/viewtopic.php?t=49112

I used a plate on my aluminum intake to lift my engine to install the headers.  It worked fine.  When I pulled the engine and trans out, I used a leveler and use installed a bolt on the front an rear head to lift it out.  When I worked in a shop, we typically just used a couple of bolts in the heads to pull an engine.

Inkara1 wrote: On the new crank or the old one?

the new one

that's what i was afraid of, i might've passed on this crank, may be a core or an unfinished reman in progress? 

IMO it needs to be seen by the nearest crank doctor for evaluation, that thrust surface looks like Joe chowdered on it with his sawzall. 

i don't see how it's even measurable?

One question for when I complete the work and put the engine back together:

I bought a water pump for it a couple of years ago, but the pump that was on it was good, turns well, is quiet, and doesn't leak, so I left it alone. Those properties still apply. But given what a pain it is to get to the pump, and also given the spotty quality of replacement parts, would I be best advised to stick with the current pump or put on the new one? The brand of the new pump is "Airtex."

The passenger side is the usual culprit for cracking and can cause exhaust noise like your original sound.  There won't be any shorty headers that will bolt on without some mods to the head pipes, at least not that I know of.  You could try to find used manifolds, but just hope you don't end up with another set with cracks.

As for the water pump, there is to be a lot said for if it ain't broke, don't fix it.  But if it is the original and since you plan to tow, it might be good insurance, especially since you already have a new one.

I'd think about welding that one crack up, but then I'd worry that the other cracks would work their way through. 

Checking eBay, there's not much. I do see a 1971 right-side manifold for $100, but not enough pictures to see if it's cracked, and shipping from Anchorage, Alaska, might be slow and expensive. There's a pair of 72-73 Mustang manifolds for $300 in Arizona, but shipping is $100 to my zip code, so at $400, I'm almost to a new pair of shorty headers at Summit for $480 plus tax with free shipping.

Question: if the passenger side manifold is prone to cracking, are there any steps I can take to keep the "new" one from also cracking? Anything I need to avoid happening to it?

IIRC, it was partially because of the heat stove for the intake which kept the heat around the manifold.  If you get the new ones ceramic coated that might help keep the temperature done to avoid them cracking.