Power estimate
Printed From: The Ford Torino Page
Category: Powertrain Specific Forum
Forum Name: 335 Series Engine Forum
Forum Description: 351C, 351M and 400 engines
URL: https://forum.grantorinosport.org/forum_posts.asp?TID=14964
Printed Date: 26-March-2026 at 5:42PM
Software Version: Web Wiz Forums 12.06 - https://www.webwizforums.com
Topic: Power estimate
Posted By: ZCowher
Subject: Power estimate
Date Posted: 13-April-2016 at 3:05AM
|
Just to get opinions from those that know more than me. (I'm grabbing a copy of the build sheet some time next week.)The rebuilt engine has : 351c stock 2v heads I don't think the valves were ported Engine Pro Cam (Melling) part # MC1733 .485 lift adv. Duration 282 Lobe Sep. 106 Keith black pistons and rings (I think 9.5-10:1 compression, I was told it was built to 71 Torino specs with my extras) *Bored .030 over Edel brock performer intake Edel brock 600 cfm carb part number 1406 hedman long tube headers stock crank stock oil pump and pan accel super stock coil pertronix ingnitor one ignition What should I expect from this engine. Hp and Torque wise?
------------- ZC 2016 F-150 xl 2.7 liter 73 Gran Torino Formal roof, Ten damn years, and its almost there. |
Replies:
Posted By: Nuggets
Date Posted: 13-April-2016 at 6:48AM
|
You don't port valves....you only port ports/runners cam seems very mild, intake isn't anything fancy its just a reduced weight version of stock, your pistons and rings aren't the only thing to consider when checking CR you need the HG compressed thickness, head skim if any and deck height as all things changed, same with over size or stock pistons ------------- Barnaby 429 powered 73 Stripper.....no comfort, just noise! |
Posted By: ZCowher
Date Posted: 13-April-2016 at 6:52AM
Yeah that was a whoops on my end. I'll get the build sheet some time next week and know everything in detail shortly. It was bored .030 over as well. ------------- ZC 2016 F-150 xl 2.7 liter 73 Gran Torino Formal roof, Ten damn years, and its almost there. |
Nuggets wrote:Posted By: Nuggets
Date Posted: 13-April-2016 at 7:04AM
|
.030 will raise the CR, will also need the head type are yours open or closed chamber? If its the 73 car odds are they're open, if its the 72 odds are they're closed ------------- Barnaby 429 powered 73 Stripper.....no comfort, just noise! |
Posted By: ZCowher
Date Posted: 13-April-2016 at 7:05AM
|
The engine came out of a 71 mercury Cougar ------------- ZC 2016 F-150 xl 2.7 liter 73 Gran Torino Formal roof, Ten damn years, and its almost there. |
Posted By: Nuggets
Date Posted: 13-April-2016 at 7:08AM
|
71 would be closed chamber then, so yeah somewhere in the high 9s to mid 10s I'd look at stock power for that year and say add 30, maybe 45.....you haven't really added much to it ------------- Barnaby 429 powered 73 Stripper.....no comfort, just noise! |
Posted By: ZCowher
Date Posted: 13-April-2016 at 7:14AM
|
http://shop.advanceautoparts.com/p/spartan-atk-engines-cylinder-head-remanufactured-2f38/99980455-P?searchTerm=cylinder+head#
I had to replace one of the cylinder heads. This is the one I bought and it matched the other one. ------------- ZC 2016 F-150 xl 2.7 liter 73 Gran Torino Formal roof, Ten damn years, and its almost there. |
Posted By: Nuggets
Date Posted: 13-April-2016 at 7:31AM
|
Thats an open chamber head if the pics right....low CR, if you've built a 10.5:1 motor using them then good luck....it'll detonate like no tomorrow unless its got specialist pistons Closed chamber 2v are pretty rare, I'd forgotten about that, closed top, open on bottom  ------------- Barnaby 429 powered 73 Stripper.....no comfort, just noise! |
Posted By: ZCowher
Date Posted: 13-April-2016 at 7:34AM
Probably safer to say 9:5 to 1 then. Maybe I'll just bum a compression tester from the school tonight and find out for sure. lol  ------------- ZC 2016 F-150 xl 2.7 liter 73 Gran Torino Formal roof, Ten damn years, and its almost there. |
Posted By: Nuggets
Date Posted: 13-April-2016 at 7:39AM
|
edit; google knows all Compression ratio ranged from 9.5:1 in 1970 to 8.0:1 in 1973 If its 9.5 then you'll be safe, over 10 then watch out ------------- Barnaby 429 powered 73 Stripper.....no comfort, just noise! |
Posted By: Big Bird
Date Posted: 13-April-2016 at 10:41AM
|
Eddy performer intake... you DID get the one for 2v heads, right? One for 4v heads will have a SERIOUS port mismatch. Your 1406 is more of a "slap-it-on-and-it-runs-better-than-stock-without-any-fuss-fidgeting-or-tuning" carb than a high-performance carb. Not a problem, but you are leaving some performance on the table. I have the same one because I didn't feel like dealing with a Holley and couldn't find a 4300. Boring the block 30 over doesn't add power, and doesn't add compression. It's done to clean up the cylinders for a rebuild. The new pistons are where you would add compression. Don't be too down on the open chambers, if you will be driving on the street, and the engine was built for open heads, you will never know the difference. ------------- "What we do in full frontal view, is more honest than your cleaned-up mind." Randy 1979 T-Bird 2005 F-150 STX RCSB 4.6, 3.55 LSD How the Heck does a REGULAR CAB SHORTBED weigh over 5200 pounds? |
Posted By: Nuggets
Date Posted: 13-April-2016 at 10:50AM
|
Boring the block 30 over should increase the compression....you're increasing the available swept volume but its got to fit into the same head chamber ------------- Barnaby 429 powered 73 Stripper.....no comfort, just noise! |
Posted By: Nuggets
Date Posted: 13-April-2016 at 10:54AM
|
Bumps it up about .2 from a quick calculation....not a huge amount but still will make a difference if you're close to the limit ------------- Barnaby 429 powered 73 Stripper.....no comfort, just noise! |
Posted By: Big Bird
Date Posted: 13-April-2016 at 11:20AM
|
Although you do increase the cylinder volume, it's a negligible amount and the replacement pistons typically take it into their design when manufacturing. It's not really a power adder, more of a step in the re-machining process. also, unless the piston and head gasket is a zero-deck design, the area inside the cylinder at TDC is larger as well. Actual performance gains from an overbore of 30 thousandths, with all else being the same is minimal. On a 351 with a 4" bore, you get about 5 extra cubic inches displacement. That is a little over 1%. Not trying to beat a dead horse, but it's not the overbore making power, it's what you do AFTER the machine work that adds power. ------------- "What we do in full frontal view, is more honest than your cleaned-up mind." Randy 1979 T-Bird 2005 F-150 STX RCSB 4.6, 3.55 LSD How the Heck does a REGULAR CAB SHORTBED weigh over 5200 pounds? |
Posted By: Nuggets
Date Posted: 13-April-2016 at 11:27AM
|
I'd think on a proper rebuild it should be zero decked....depends whats been done though, if it has been then you will see a .2 increase in CR ------------- Barnaby 429 powered 73 Stripper.....no comfort, just noise! |
Posted By: lynchster
Date Posted: 13-April-2016 at 11:55AM
What's the lift and duration @ .050? ------------- Chuck 72 Gran Torino Sport 13 Taurus SHO "Mr Pig" |
Posted By: lynchster
Date Posted: 13-April-2016 at 12:17PM
Nevermind, found it. Duration @.050 I .204 / E .214 Advertised I .282 / E .292 Lift I .484 / E .510 Lobe separation I 106 / E 118 Range 1500 - 4000 rpm I'm going to say from what I've read your cam is all wrong assuming your compression is that high. Your lobe separation of 106 really had me thrown. That's bracket racing lobe separation with towing cam lobes. Add both the intake and exhaust then divide and the 112 would make more sense. Here's a few links from what research I've been doing. I never get these to work as intended so you may have copy and paste them, http://www.crankshaftcoalition.com/wiki/Cam_and_compression_ratio_compatibility http://www.crankshaftcoalition.com/wiki/How_to_choose_a_camshaft http://www.hotrod.com/how-to/engine/ccrp-9812-secrets-of-camshaft-power/ ------------- Chuck 72 Gran Torino Sport 13 Taurus SHO "Mr Pig" |
Posted By: Rockatansky
Date Posted: 13-April-2016 at 1:45PM
|
2V heads only came as open chamber in the US AUS got closed chamber heads to reduce the chamber volume to match the 302 cu in displacement 'Aussie' closed chamber heads came off of 302C's ------------- 72 GT Ute |
Posted By: californiajohnny
Date Posted: 13-April-2016 at 3:19PM
|
i just noticed this... but isn't the head on the top a sb chevy? sure looks like it to me
------------- JOHN 74 GRAN TORINO S&H CLONE 74 VETTE CUSTOM 90 S10 BLAZER 4X4 LIFTED 77 CELICA CUSTOM 75 V8 MONZA SUPERCHARGED 79 COURIER VERT. SLAMMED 75 VEGA V6 5 SPD 70 CHEV C10 P/U 68 MUSTANG FB CONVERSION |
Posted By: Big Bird
Date Posted: 13-April-2016 at 3:47PM
Them sure do look like paired intake ports, with exhausts side-by-side on the center cylinders... ------------- "What we do in full frontal view, is more honest than your cleaned-up mind." Randy 1979 T-Bird 2005 F-150 STX RCSB 4.6, 3.55 LSD How the Heck does a REGULAR CAB SHORTBED weigh over 5200 pounds? |
Posted By: Power Surge
Date Posted: 13-April-2016 at 3:59PM
As Big Bird said.... you will not increase compression with a larger bore. First off, it's a barely measurable amount. You're not increasing volume that much. Second, even though you are technically allowing more air in the cylinder, you also have a LARGER cylinder. So there is no increase in compression. Piston rings do not go all the way to the top of the cylinder. When the piston is all the way up, you are still compressing air in a larger area. So the minimal extra air you're taking in, is also being compressed in a larger container. They negate each other. You get no compression benefits. As for the original poster's question.... I would feel your setup, if it's about 9.5:1, would be about 300 hp. ------------- Sal Mennella 73 GTS 351 CJ 75 Cougar XR7 73 Ranchero - 5.0 Coyote swap - in progress Past Torinos - 72 Gran Torino, 75 Gran Torino, 75 Elite |
Posted By: Rockatansky
Date Posted: 13-April-2016 at 4:34PM
|
swept bore area vs chamber volume, a larger dia bore will have more CR against the same size chamber not a whole  of a lottypical standard bore 351C w/ 1972 8cc dish pistons comes up at 8.11:1 bore it .030" and it makes 8.21:1 I use .047" thick x 4.1" dia gasket (Fel-Pro 8347PT=1), .035" deck clearance (stock uncut block) http://www.network54.com/Forum/136503/thread/1329504375/last-1357658605/View+Thread" rel="nofollow - http://www.network54.com/Forum/136503/thread/1329504375/last-1357658605/View+Thread http://raceabilene.com/kelly/hotrod/compression.html" rel="nofollow - http://raceabilene.com/kelly/hotrod/compression.html
------------- 72 GT Ute |
Posted By: ZCowher
Date Posted: 13-April-2016 at 5:08PM
It is a 2v intake for sure. As far as the CAM goes I think I read the page correctly but the part number is definitely MC1733 and its a melling cam sold by engine pro. What kind of torque numbers ? ------------- ZC 2016 F-150 xl 2.7 liter 73 Gran Torino Formal roof, Ten damn years, and its almost there. |
Posted By: californiajohnny
Date Posted: 13-April-2016 at 5:49PM
"torque numbers" you guys don't happen to have a chassis dyno at the school do ya??? 
------------- JOHN 74 GRAN TORINO S&H CLONE 74 VETTE CUSTOM 90 S10 BLAZER 4X4 LIFTED 77 CELICA CUSTOM 75 V8 MONZA SUPERCHARGED 79 COURIER VERT. SLAMMED 75 VEGA V6 5 SPD 70 CHEV C10 P/U 68 MUSTANG FB CONVERSION |
Posted By: ZCowher
Date Posted: 14-April-2016 at 12:43AM
Unfortunately not that , not even an engine dyno. This school is more for a general mechanic than performance.That would be soo cool though, even an engine dyno ------------- ZC 2016 F-150 xl 2.7 liter 73 Gran Torino Formal roof, Ten damn years, and its almost there. |
Posted By: ZCowher
Date Posted: 14-April-2016 at 12:51AM
|
This came from engine pro, to answer cam questions ------------- ZC 2016 F-150 xl 2.7 liter 73 Gran Torino Formal roof, Ten damn years, and its almost there. |
Posted By: Nuggets
Date Posted: 14-April-2016 at 12:38PM
Yes 302c Aussie heads are closed but at one point 351c 2v closed chambers did exist too, they were short lived but shared the same cc chamber size of the 4v and the same kidney shame but they had the 2v runners and valves
------------- Barnaby 429 powered 73 Stripper.....no comfort, just noise! |
Posted By: Nuggets
Date Posted: 14-April-2016 at 12:40PM
I'm going to agree to disagree here.... Whilst you are right in that the piston area becomes larger we don't know the spec of the build....if he's gone with a zero deck it would bump it up, as I already said it wont be much but on some engines its enough to push them into detonation territory ------------- Barnaby 429 powered 73 Stripper.....no comfort, just noise! |
Posted By: ZCowher
Date Posted: 15-April-2016 at 1:40AM
|
By my calculations, and speaking to the machine shop I had it at, it is 10:1 compression ------------- ZC 2016 F-150 xl 2.7 liter 73 Gran Torino Formal roof, Ten damn years, and its almost there. |
Posted By: Nuggets
Date Posted: 15-April-2016 at 2:02AM
|
Good luck with that then, 10:1 on open chamber heads is a lot of compression! I'd get them to double check it unless your cam is giving you a much lower dynamic ratio that is going to have issues detonating ------------- Barnaby 429 powered 73 Stripper.....no comfort, just noise! |
Posted By: Rockatansky
Date Posted: 16-April-2016 at 4:48AM
yes I'm aware that there are different chamber volume heads used in AUS, the larger volume chambers were likely used on 351 engines, but still, not in the US to complicate matters AUS also produced open chamber 351C heads I recall a guy bought a set from an importer (I forget which one) & they were not a matched pair, date codes a decade off & chambers so different it would be foolish to use them as a set. seller wouldn't budge said they're not damaged & suitable for rebuilding so sale was good here's a page to ID AUS heads while bolted on an engine, not complete but can be a help http://351cleveland.wikifoundry.com/page/Ford+Aussie+302C+Heads" rel="nofollow - http://351cleveland.wikifoundry.com/page/Ford+Aussie+302C+Heads ------------- 72 GT Ute |
Posted By: Rockatansky
Date Posted: 16-April-2016 at 5:05AM
|
as to the actual CR of this build, can we get the piston part number to see if it's a flat top or has a dome or dish? https://www.uempistons.com/index.php?main_page=index&zenid=64b1f689567bca73c383d6f1dc80dfa3&cPath=3_4_22&sort=5a&filter_id=6&eng_filter=351&rod_filter=5.778" rel="nofollow - https://www.uempistons.com/index.php?main_page=index&zenid=64b1f689567bca73c383d6f1dc80dfa3&cPath=3_4_22&sort=5a&filter_id=6&eng_filter=351&rod_filter=5.778 ------------- 72 GT Ute |