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Initial Ignition Timing Setting Question.

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dave302 View Drop Down
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    Posted: 17-July-2014 at 2:48PM

I want to ask a question about the base (initial ignition) timing adjustment on later model (1972 through 1985) ford 429 and 460 engine's that have had an early (1968 through 1971) timing gear set installed on them.
 

There is also another question written below, it is highlighted in red. the question is about how the ford motor company had retarded their crankshaft sprockets/gears on the 1972 and newer 429 and 460 engines, to reduce exhaust emissions. Do you know how this could be possible? How can retarding the the crankshaft gear eight degrees reduce emissions? I have done many long exhaustive searches on the following subjects, but i could not find any answers.

The reason that i am asking you this, is because i have a friend with a 1975 ford 460 engine and his engine has an early timing gear set installed on it. His timing gear set is exatly like the timing gear sets that are installed on the 1968 through 1971 ford 429 and ford 460 engines from the factory. These timing sets are almost always referred to as "straight up timing sets".


Many aftermarket timing chain/gear set's will have an option for setting the camshaft to 4* retarded (which is like the 1972 and newer 429 and 460 engines were set to from the factory). and it will also have an option to set it to 0* "straight up" timing, (which is like the 1968 through 1971 429 and 460 engines from the factory). and it will also have an option to set to 4* advanced timing.


We are trying to diagnose if his base (initial) ignition timing is set too far advanced at idle, because after his engine has reached operating temperature (warm/hot), it sounds like the starter motor is almost trying to turn the engine backwards when he tries to restart it. I have seen this problem happen many times in the past, when the base timing of an engine is set too far advanced. But this warm/hot starting problem could also possibly be related to a starter motor that has worn parts inside of it, and that is what we are trying to figure out.


We will not need help diagnosing if there is a starter problem, but we do want to make sure that his base timing is not set too far advanced.


I am not an expert on adjusting initial ignition timing, so please forgive me if i am wrong about any of the following statements.

Most of the following information has been taken from professional repair manuals of the 1968 through 1978 ford, lincoln and mercury 429 and 460 engines.


The following information only refers to the standard 429 and 460 engines. it does not refer to the cobra jet, super cobra jet or police engines.

We believe that the early style "straight up" timing chain and gear set (that is installed on my friends engine), has already advanced the valve timing on it. So it will now need a lower/more retarded initial ignition timing setting, like on the earlier (1968 through 1971) engines. But i do understand that we could be wrong about this.

My friends engine has it's initial base timing adjusted to 10* BTDC (which is 10 degrees before top dead center) at idle. But the 1968, 1969 and 1970 429 and 460 engines had their base timing set at 6* BTDC from the factory. The 1971 429 and 460 engines had their base timing set at 4* BTDC from the factory.


The 1968 through 1971 429 and 460 engines had a crankshaft sprocket/gear that was advanced 8 degrees (when compared to the 1972 and newer crankshaft sprockets) originally from the factory. it opened the intake valves at 16* BTDC on the intake stroke.

Starting in 1972 the ford motor company had installed a crankshaft sprocket that was retarded 8 degrees (when compared to the 1971 and older crankshaft sprockets) on these engines, to reduce exhaust emissions. Question: Do you know exactly how this would have reduced exhaust emissions? After the crankshaft sprocket was retarded 8 degrees in 1972, the intake valves would then open at 8* BTDC on the intake stroke. So 1971 was the last year of these "Straight up" timing gears from the factory.


1972 was also the first year that these 429 and 460 engines had their base (initial ignition) timing advanced to 10* BTDC from the factory. This is the reason that i think my friends base initial timing should be timed between 4* to 6* BTDC, instead of 10* BTDC like it is now. But i do understand that i could be wrong about this part.


The 1974 460 engines had their base timing set to 14* BTDC from the factory. This was also the first year that the spark plugs started to be gapped at .044" from the factory. They used to be gapped at .034" before 1974. 1974 was also the first year that electronic ignitions were installed on the 460 engines.


The base timing on the 1975 460 engines (in the 49 states of the U.S.A.) was set to 10* BTDC from the factory and it was set to 14* BTDC on the california 460 Engines.


The 1976 and 1977 460 engines had their base timing set to 14* BTDC from the factory in all 50 states.


The 1978 460 engines had their base timing set to 10* BTDC from the factory in all 50 states.


I do understand that with the addition of a high performance camshaft and high performance engine parts (like high compression pistons and high performance/high compression cylinder heads), a high performance intake manifold, a high performance ignition system and a high performance exhaust system, will all change the need for different initial base timing settings on different engines. So there is no real "correct" initial base timing settings for any engine.


My friends engine (that i am talking about here) is almost all stock original, with an original equipment/stock type camshaft, original equipment pistons, original equipment cylinder heads, an original equipment crankshaft, an original equipment carburetor and original 8 to 1 compression ratio.

My friend has spoken to the employees of a few different car repair shops, and they had all said that they can adjust his initial base timing to 10* BTDC (like it says to adjust it to on the valve cover decal/sticker), but none of them seem to know how to adjust it to compensate for the early style timing gear set that is installed on it now.
 
If any of you have a later model 429 or 460 engine (or an earlier one), with a straight up timing chain and gear set installed on it, what do you have your base initial timing set to?
 
It also might be possible that the ford motor company had also retarded the crankshaft gears on all of their 250, 302, 351W, 351C and 400 engines, on or after the year of 1972, so i would appreciate it if anyone who has one of these engines will also answer to this subject.
 
Thank you for any information that you can give to us.

 



Edited by dave302 - 17-July-2014 at 9:03PM
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 17-July-2014 at 3:12PM
difficult cranking & bucking when hot is a sign that the base or initial ignition timing is too advanced,
it can also be a symptom of a heat damaged starter &/or both
 
one point you haven't mentioned is Total Timing, or Initial + Mechanical
 
the amount of mechanical advance that the distributor dials in with rpm will not be the same for distributors with different initial timing specs. if the initial spec is 16* for example, the mechanical will be around 20* for a Total of 36*. if the Initial is 10*, the mechanical will be around 26* for a Total of around 36*. again, not specific to the 429/460 but probably in the ballpark
 
performance years the Initial was high & the mechanical was low to achieve the desired total, then in the emissions years they reduced the initial & increased the mechanical to compensate. and along came ported vacuum. these poor dogs are running off initial only at idle & the vacuum kicks in just above idle as the car tries to pull off from a stop
 
I'd check to see what the total his dizzy is kicking out & decide from there what you want to set the base at... maybe a custom curve job by Scotty J at Re-Incarnation Automotive? Wink
 
too bad he changed his site, I like the old one http://www.reincarnation-automotive.com/home
 
IMO there's no rule of thumb to setting base timing for smog or non-smog cam timing, the spark in all cases is in relation to the crank/piston position in regards to TDC. the timing sprockets are no different than various performance or stock camshaft valve timing events being different, they dictate the cylinder filling characteristic of the engine... the initial & mechanical need to produce a total that makes best power, doesn't destroy the engine & allows it to crank hot


Edited by Rockatansky - 17-July-2014 at 3:17PM
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Big Bird Quote  Post ReplyReply Direct Link To This Post Posted: 17-July-2014 at 3:32PM
Other possibility for the kicking back is overheating/heat soak which will also occur if pinging due to crap gas (87 octane may be a problem, early 429/460 liked premium gas 91-93 octane).
As Rockatansky stated, the initial timing is based on the distributor advance curve, and isn't directly related to the crank gear being retarded. Retarding the crank gear retards the camshaft, which delays the intake event, which makes the engine's volumetric efficiency go down, which makes the engine act like it has a lower compression ratio, which reduces hydrocarbons and oxides of nitrogen and makes the car run like Censored. (This was a half-assed strategy for smog control, Essentially, the car ran so poorly that you didn't want to drive it)
If you are still running the original distributor, start with the factory setting and retard it, or advance it until you find the sweet spot. Personally, I would find a distributor for thr 67-71 era engines.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote californiajohnny Quote  Post ReplyReply Direct Link To This Post Posted: 17-July-2014 at 5:19PM
i'd go with the zero on the timing chain setup. if in fact some gears were retarded, then maybe they had different balancers with different timing marks? to compensate for the retarded gear??? IDK just a thought. are you running  points or electronic dist.? i ask because point settings can alter your timing readings slightly. and is your idle setting extra high,as that can cause the centrifugal advance to add to the timing, just another thought. and also how is your vacuum advance routed? to the port on the carb that only pulls vacuum when the throttle is opened off of idle? or is it pulling vacuum all the time while idling?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dave302 Quote  Post ReplyReply Direct Link To This Post Posted: 17-July-2014 at 6:49PM
Thank you for all of the answers, we appreciate it.
 
Originally posted by californiajohnny californiajohnny wrote:

Are you running points or an electronic distributor? He has an electronic ignition. And is your idle set extra high? as that can cause the centrifugal advance to add to the timing. No, his curb idle is set to 725 RPM's with the transmission in park and 625 RPM's with the transmission in drive, while the engine is warm/hot at operating temperature.  How is your vacuum advance routed? to the port on the carb that only allows vacuum while the throttle is opened or off idle? or is it pulling vacuum all the time while idling? The vacuum advance diaphram rubber hose is routed correctly, it is connected to the ported vacuum on the carburetor, that only allows vacuum while the throttle is opened or off idle. Thank you for asking.


Edited by dave302 - 17-July-2014 at 6:56PM
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 18-July-2014 at 3:52AM
you can't even trust the '0' on aftermarket multi key sets, here's 3 different brands all keyed to '0'
 
the 0 is only a reference to differentiate it from the + & - slots, there's no guarantee that it's the same as factory 0, or if it's factory smog or non-smog 0. the only way to be sure what your cam is set to is to use the degreeing tools. if you find that a key slot provides 1* advance from you target I would use that slot as the chain will likely slightly stretch rather quickly & you'll be right on until it stretches itself to whipped licorice 
 
to get exactly the position I wanted I found that if you skip a tooth in on direction & use the key slot to bring it back you can add versatility to the timing set. now I'm having 2nd thoughts about where I have it set & may change it... ? Aaaaagh!
 
just had a thought, what if they marked the +4 on the wrong tooth? Ouch
 
 
 
 
 


Edited by Rockatansky - 18-July-2014 at 3:55AM
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Post Options Post Options   Thanks (0) Thanks(0)   Quote aquartlow Quote  Post ReplyReply Direct Link To This Post Posted: 18-July-2014 at 5:56AM
Rockatansky,
 The last photo shows that the cam timing is either 8' retarded or that the crank is 4' advanced. If 0' or straight-up timing is desired, the crank's timing gear "dot" will be directly above the crank's keyway. If cam timing is to be 8 degrees advanced, the mark will be on the right side of the keyway(retarding the crank 4 degrees). I fought this when using a late model timing set and having to set the crank gear 4 degrees advanced to get my cam timing to the "straight up" position. I found even using a decent quality aftermarket timing set is no guarantee of getting correct cam timing WITHOUT degreeing the cam, just too many variables in the machining process between crank, cam and timing set. I went round-n-round with ignition timing, carb issues and exhaust popping, I ended up opening the engine and changing to a Cloyes 9-3122 timing set. I found the first set was installed 6 degrees retarded even using a Comp Cam(they are ground 4 degrees advanced) and the timing gear set at 4 degrees advanced Ouch. Once the new Cloyes set was installed & degreed to as close to straight up as possible (1 degree advanced) and mirrored what specs Comp Cams recommended. The engine ran much better, reduced the burning eyes syndrome, revved quicker and the exhaust no longer popped. Hope this helps. Todd
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 18-July-2014 at 7:18AM
IIRC I was shooting for 108* Intake Center Line, or TRUE 'straight-up' for the cam, which has 4* advance ground in so 'by the book' it should be installed to 104* ICL
it's just a test mule temporary lets see if this block & heads are good build but now I'm thinkin I'd like to see how it's supposed to run from the grinder with the advance Wacko
 
looks like what I did was skip a tooth to retard the cam & bring it back with the advance key position to get exactly what I thought I wanted at the time... 108* ICL Confused
 
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Edited by Rockatansky - 18-July-2014 at 7:20AM
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Post Options Post Options   Thanks (0) Thanks(0)   Quote aquartlow Quote  Post ReplyReply Direct Link To This Post Posted: 18-July-2014 at 7:54AM
Dealing with cam timing/retarded vs straight-up timing sets reminded me of the first time in mathematics class(eons ago) when I had my first dealings with negative numbers, algebra, geometry and trigonometry, all rolled into one Wacko. If you say you're good, you're good Wink. Todd
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 18-July-2014 at 8:30AM
it sure can twist the grey matter! I thought it was good at the time but I wish the cover was still off
 
pretty sure I can still check it with the cover on though, I only need TDC & lobe position
 
once for grins I advanced a full tooth on a AMC 232 6-pop, it was out of wind right off idle 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote unlovedford Quote  Post ReplyReply Direct Link To This Post Posted: 18-July-2014 at 8:32AM
Not to throw another variable in here, but about a year ago, I was having horrible starting issues with my 429 1972 wagon. It would fire right up when cold, but give the indication the timing was too advanced when warm. Went through timing it several times, fresh tune, fresh battery, checked the starter. Nothing would help. It was also occasionally intermittent, which only added to the frustration.

Finally I went to start it in a lightning storm on afternoon and the starter would turn 1 revolution forward, then back crank. Tried 6 times and it stuck in start position (not the switch) it the engine would fire, then crank, fire then crank (continuous cycling) without me even in the car. Even with the ignition off! Yanked the cable off, soaking wet, lightening popping all around me and shut the hood in complete disgust.

The answer? A faulty starter solenoid. It would heat up, break down. Cool and work properly again. Over and over until I tried a force start that afternoon out of stubbornness, and it finally malfunctioned in start mode (Open? Closed?). I installed a heavy duty one from O'Reilley's and never had another issue.

This may not be your issue, but it is cheaper and faster than pulling a starter and would not hurt.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 18-July-2014 at 10:02AM
another good Hide~N~Seeker is the negative battery ground cable
 
same deal, works perfect cold but won't flow an electron hot... heat related resistance
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Big Bird Quote  Post ReplyReply Direct Link To This Post Posted: 18-July-2014 at 10:04AM
Did the balancer, pointer, and timing cover start out as a set, or are they mix-and-match? I converted a EFI mustang 5.0/32 motor to carb, and used my 302 cover and pointer with the mustang balancer. So-o-o, I have what's called a "10 o'clock" pointer and an "11 o'clock" balancer. IDK if these kinds of problems are possible for a 385 series, but it may be something to consider.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 18-July-2014 at 10:07AM
it never hurts to verify TDC once in a while, even if it's just a McDonalds straw through the spark plug hole while turning the crank slowly with a hand ratchet
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dave302 Quote  Post ReplyReply Direct Link To This Post Posted: 19-August-2014 at 6:15PM

Thank You for the answers, we appreciate it.

 
Originally posted by Big Bird Big Bird wrote:

If you are still running the original distributor, start with the factory setting and retard it, or advance it until you find the sweet spot.

Unfortunately, I can never find the perfect sweet spot for some reason. I do know when the initial base timing is too retarded, because the engine sounds as if it is idling too slow and it is not smooth. Then i will advance the timing slightly, so the engine RPM's speed up and it runs smoother. If i advance the timing slightly more the engine rpm's increase even more. This is the part that i can never get perfect. On some vehicles you can hear when spark knock in the cylinders begins due to the timing being too far advanced.


My friends car has a loud set of flowmaster 40 series (or maybe they are flowmaster 45 series) mufflers installed on it, and it is parked with the rear/back of the car up against a wall. So it is difficult to hear when the spark knock/pinging begins to happen. Unfortunately we will not be able to move the car away from the wall for quite a while. 

Here is a video that shows how to adjust the initial ignition timing. the first 8 minutes of the video is a tutorial about ignition timing, then at 8 minutes he starts the engine which is timed at 4* BTDC, then at 9 minutes and 10 seconds he advances the timing to 14* BTDC. And he says that the idle is faster than he likes it because the timing is set too far advanced. This is the part that i can never get right, how does he know that the timing is set too far advanced? can you tell me?
 
Then at 10 minutes and 4 seconds he retards the timing to 12* BTDC and he says that it is good there. He then shuts the engine off and then he re-starts it to see if it starts right up without any hesitation.
 
This example was done on a Middle-to-Late 1970's engine. This engine might still have the crankshaft sprocket retarded 8* from the factory. The engine has open headers on it.
 
To watch the video: Click Here.
 
My friend and i have not been able to check the total ignition timing/timing curve adjustment yet, but he said that he has had this engine up to 3000 RPM's and it ran good.
 
I do understand that the problem that the starter is having when the engine is warm/hot at operating temperature, could be due to a starter with worn parts/that is failing. The engine starts right up when it is warm/hot, but the starter makes a certain type of "hissing" sound. It almost sounds as if the starter is working too hard to try to turn over the engine, due to an initial ignition timing that is too far advanced. I do understand that we have probably covered that part already in this thread.
 
Unfortunately, i have been too busy recently to reply in this thread. I am not an expert on adjusting ignition timing, so please forgive me if i do not understand some of it. 
 
The starter sound is not like when there is worn teeth on the flywheel or a failing bendix gear.
 
Originally posted by Rockatansky Rockatansky wrote:

Another good Hide~N~Seeker is the negative battery ground cable, same deal works perfect cold but won't flow an electron hot... heat related resistance.
 
I have heard of that happening too, thank you for the answers.
My friend had just had a new starter-to-starter-solenoid cable (starter cable) installed recently. the old starter cable had a rip/tear in the rubber casing and the exposed copper cable had turned a very dark brown color over time. This cable would smoke slightly and it would get hot when he would try to start the engine.
 
We did a resistance test on both the new and old cables (when the cables were cool at room temperature) and there was no difference in resistance for some reason? But i would say that it is almost definetely because the cables were not hot though. We have not had a chance to start the engine since the new starter cable was installed.
 
My friend and i are both very busy, so this thread will probably move along slowly.
 
Thank you for any answers that you can give to us.
 


Edited by dave302 - 20-August-2014 at 4:09PM
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dave302 Quote  Post ReplyReply Direct Link To This Post Posted: 19-August-2014 at 6:32PM
Originally posted by Rockatansky Rockatansky wrote:

it never hurts to verify TDC once in a while, even if it's just a McDonalds straw through the spark plug hole while turning the crank slowly with a hand ratchet.
 
Thank you for the answers. This was done when the early timing chain and gear set was installed. We hope to do this test again soon though.
 
Originally posted by Big Bird Big Bird wrote:

Did the balancer, pointer, and timing cover start out as a set, or are they mix-and-match?
 
I believe that they are a matching set, but i am not 100% sure though. We are going to try to find out more about this possibility as soon as possible. Thank you for the answers.
 
Originally posted by unlovedford unlovedford wrote:

I had a starting problem similar to yours and the problem turned out to be a faulty Starter Solenoid. I replaced the Starter Solenoid with a new Starter Solenoid and there were no more problems after that.
 
This may not be your issue, but it is cheaper and faster than pulling a starter and would not hurt.
Thank you for the answers, we appreciate it. We are going to look into this possibility as soon as possible.


Edited by dave302 - 19-August-2014 at 7:11PM
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Edited by dave302 - 20-August-2014 at 12:42PM
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dave302 Quote  Post ReplyReply Direct Link To This Post Posted: 19-August-2014 at 8:41PM
Originally posted by Rockatansky Rockatansky wrote:

Once for grins I advanced a full tooth on a AMC 232 6-pop, it was out of wind right off idle 
 
I have a similar question that pertains to this topic: I have a friend with a ford 460 engine, his engine has a crane H-288-2 hydraulic camshaft installed inside of it.
The cam specifications are:
Intake valve lift: 0.520"
Exhaust valve lift: 0.533"
Camshaft operating range: 2500 to 5500 RPM's.
The entire camshaft specifications card is listed at the bottom of this post.
 
This is only about four steps up from an original equipment 460 camshaft from the factory.
 
He has not had a chance to do all of the engine and drivetrain tuning yet, to make this cam work at its best. Like installing the proper stall converter, a performance intake manifold and performance carburetor. Installing a 3:25 to 3:50 rear end gears. (his car has a 2:75 rear end gears now). An aftermarket coil (he has an original type of coil now). I have probably left some things out, but i will get to my question...
 
He has an adjustable timing chain and gear set installed on it now. This timing gear set has provisions for retarding the cam 4 degrees, it also can be adjusted to zero (straight up) timing, and it can be advanced 4 degrees also. His cam timing gear is currently set to zero.
 
He has also not decided yet if he is going to keep this cam installed in the engine, or install a milder cam.
 
So here is my question: Someone had told him that if he advances the camshaft timing gear to four degrees advanced (instead of zero/straight up like it is now), the engine RPM's will be more efficient between 2000 to 5000 rpm's (instead of between 2500 to 5500 rpm's like it is now. Is this true?
 
He does understand that this engine with this camshaft installed in it, will never run perfect without adding on all of the proper parts and accessories like i have mentioned above, and like they recommend in the camshaft card specifications. But he had said that it will be cheaper and easier for him to advance the camshaft timing 4 degrees, than it would be to replace the camshaft with a more milder one, or to add on all of those extra engine and drivetrain parts at this time.
 
The main problem will probably be that the engine will not have enough rpm's (at only 2000 rpm's) for the .522" intake lift and .530" exhaust lift to run efficient. But he said that it might be better than it is now. What do you think about this subject?
 
He had said that the only thing that he would possibly be worried about happening is: if the valves could possibly hit the pistons, since the camshaft has been advanced 4 degrees, do you think that this could possibly happen? 
 
Below is the cam card specifications for the crane H-288-2 camshaft that is currently installed in his engine.

Manufacturer's Part Number:354552
Product Line:Crane PowerMax Cam
Cam Style:Hydraulic flat tappet
Basic Operating RPM Range:2,500-5,500
Intake Duration at 050 inch Lift:226
Exhaust Duration at 050 inch Lift:230
Advertised Intake Duration:288
Advertised Exhaust Duration:292
Intake Valve Lift with Factory Rocker Arm Ratio:0.522 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio:0.530 in.
Lobe Separation (degrees):112
Grind Number:H-288-2
Computer-Controlled Compatible: No
 
 Thank you for any answers that you can give to us.


Edited by dave302 - 19-August-2014 at 9:27PM
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 20-August-2014 at 11:09AM
yes it's correct that running the cam in the advanced position of the timing keyways will lower the effective power range in the rpm band. notice that Max Intake Lift occurs at 107*, Max Exhaust Lift occurs at 117* and the lobe separation is given as 112*
 
this cam has 5* already 'ground in', advancing it 4* at the crank will relate to 2* at the cam making the Intake Center Line at 105*... theoretically 
 
cylinder pressures will be slightly higher making the possibility of detonation / ping a little more likely,
 
and yes the pistons will come a little closer to the valves but I doubt they're anywhere in the worry range if the heads &/or block are not milled drastically
 
72 GT Ute
   
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dave302 Quote  Post ReplyReply Direct Link To This Post Posted: 20-August-2014 at 11:33AM
Thank You for the answers.
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