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06-22-2010, 02:02 PM
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CC Member
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Join Date: Apr 2009
Location: Bethesda,
MD
Cobra Make, Engine: CSX 6022, navy blue, period correct 427 SO
Posts: 2,154
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Not Ranked
My repro of the Shelby sales literature shows that the street cars were rated by Shelby at 425HP and the comp cars at 480HP. Probably more realistic as the comp cars were modified. The repro info could be fabricated, but doesn't seem to be.
__________________
“There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.”
www.partskeeper.com
(Less time searching, more time wrenching & driving)
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06-22-2010, 02:04 PM
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Half-Ass Member
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Join Date: Jun 2005
Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
Posts: 22,005
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Not Ranked
... and btw, that "K" camshaft that is listed in the specs. That's my cam. Yeah, baby.
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06-22-2010, 02:05 PM
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CC Member
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Join Date: Apr 2009
Location: Bethesda,
MD
Cobra Make, Engine: CSX 6022, navy blue, period correct 427 SO
Posts: 2,154
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Not Ranked
Quote:
Originally Posted by patrickt
Uhhh, I just happened to have this one handy.
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This has the alloy heads, so would be a comp car, no? Didn't only the comp cars have alloy heads?
__________________
“There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.”
www.partskeeper.com
(Less time searching, more time wrenching & driving)
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06-22-2010, 03:35 PM
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Senior Club Cobra Member
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Join Date: Jul 2002
Cobra Make, Engine:
Posts: 15,712
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Not Ranked
Hmmm, good question about the alloy heads. I thought only a FEW of the comp cars got them, not all of them? For Le Man's I believe Shelby went with a iron high riser head. I wonder which was the better head, alloy of that time or iron high riser? Of course the alloy heads had a weight advantage.
"American Muscle Car" had a show about legend vs reality where they had a shop assemble a number of old school engines using only stock parts that were available when engines were on the street. No modifications were allowed with the exception of an .060 overbore. The FE 427 was probably lucky to get half that for an overbore. Here are the results, the HEMI is particularly note worthy, rated by Chrysler at 425 horse. Uh huh, and pigs fly!
The Chevy 409/409 ..........................406 HP
The Ford 427/425 Tunnel Port..............637 HP
The Pontiac 421/421 SD......................488 HP
The Chrysler 426/425 Street Hemi.........820 HP
The Chevy 427/430 L-88......................527 HP
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06-22-2010, 03:43 PM
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CC Member
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Join Date: Apr 2009
Location: Bethesda,
MD
Cobra Make, Engine: CSX 6022, navy blue, period correct 427 SO
Posts: 2,154
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Not Ranked
This should be a fun conversation. I am going to go and get some popcorn.
__________________
“There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.”
www.partskeeper.com
(Less time searching, more time wrenching & driving)
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06-22-2010, 03:46 PM
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Senior Club Cobra Member
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Join Date: Feb 2007
Cobra Make, Engine: KMP 539, a Ton of Aluminum
Posts: 9,591
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Not Ranked
Quote:
Originally Posted by Excaliber
Hmmm, good question about the alloy heads. I thought only a FEW of the comp cars got them, not all of them? For Le Man's I believe Shelby went with a iron high riser head. I wonder which was the better head, alloy of that time or iron high riser? Of course the alloy heads had a weight advantage.
"American Muscle Car" had a show about legend vs reality where they had a shop assemble a number of old school engines using only stock parts that were available when engines were on the street. No modifications were allowed with the exception of an .060 overbore. The FE 427 was probably lucky to get half that for an overbore. Here are the results, the HEMI is particularly note worthy, rated by Chrysler at 425 horse. Uh huh, and pigs fly!
The Chevy 409/409 ..........................406 HP
The Ford 427/425 Tunnel Port..............637 HP
The Pontiac 421/421 SD......................488 HP
The Chrysler 426/425 Street Hemi.........820 HP
The Chevy 427/430 L-88......................527 HP
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Well, at least the L88 is believable.
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06-22-2010, 03:57 PM
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CC Member
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Join Date: Jul 2008
Location: Driftwood,
TX
Cobra Make, Engine: Contemporary Cobra, 427 side oiler
Posts: 1,850
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Not Ranked
Quote:
Originally Posted by patrickt
FWIW, my copy of Bil Carroll's Fooorrd Performance Guide lists the specs of perhaps half a dozen of the different Shelby 427 engines, some with horsepower numbers over 500. Aluminum heads, compression ratios, all were different. I can scan and post those pages for you this evening, if you would like.
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Nope, I've got the book and know it well. I guess this was in part my earlier point. A stock Ford Galaxie side oiler was not a 500HP engine, not even close. Only with aluminum heads, 2x4 carbs, higher compression and your coveted camshaft could Shelby get 505HP. Now of course someone will come along here shortly and say that 505 was really 600.
So, if I Doug or I want a solid 500 HP on a legitimate dyno we need at LEAST stage 2 heads and possibly a compression bump.
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06-22-2010, 04:13 PM
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Senior Club Cobra Member
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Join Date: Feb 2007
Cobra Make, Engine: KMP 539, a Ton of Aluminum
Posts: 9,591
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Not Ranked
I think Ernie's sideoiler made 667 HP with open headers, 12.5 CR and not one modern component or so he claims.
Now, the Hawaiian dyno operator, may have been similtaneously waxing his surfboard while talking to cute bikini-clad Hula chick and eating his mixed plate lunch, after previously smoking some of those funny cigarettes or something, as he was dyno'ing Ernie's engine, but no matter.
Just kidding Ernie. No diatribes necessary.
I know you engine builders out there sneak a few tricks in there to add HP and claiim it's stock. Just ask the folks who race in the F.A.S.T. class for musclecars.
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06-22-2010, 04:17 PM
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Senior Club Cobra Member
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Join Date: Jul 2002
Cobra Make, Engine:
Posts: 15,712
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Actually, as I mentioned earlier, THAT version of the engine had one very important modern part. The solid roller cam from hell that didn't even begin to make power until about 3,000 rpm.
90 plus horse power loss with the side pipes.
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06-22-2010, 04:28 PM
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Half-Ass Member
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Join Date: Jun 2005
Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
Posts: 22,005
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Not Ranked
Quote:
Originally Posted by elmariachi
So, if I Doug or I want a solid 500 HP on a legitimate dyno we need at LEAST stage 2 heads and possibly a compression bump.
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I'm running 10.6 to 1 compression, aluminum Edelbrocks with just a smidge of port matching, 20 extra cubic inches over the 427, the 245/245 .525 114 LSA old school "K" cam, new school Erson roller rockers, a simpleton Holley 4160 and I'm probably right around 500 with no sidepipes and no belts -- and that translates to an honest 450 horsepower with everything hooked up.
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06-22-2010, 05:06 PM
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Senior Club Cobra Member
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Join Date: Feb 2005
Posts: 651
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Not Ranked
Earlier today I found an avatar that depicted a man with a long stick. The man was continually beating a dead horse.
I couldn't insert that avatar into a REPLY for this thread because the file was too large.
David
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06-22-2010, 05:17 PM
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Senior Club Cobra Member
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Join Date: Feb 2007
Cobra Make, Engine: KMP 539, a Ton of Aluminum
Posts: 9,591
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Not Ranked
Quote:
Originally Posted by 601HP
Earlier today I found an avatar that depicted a man with a long stick. The man was continually beating a dead horse.
I couldn't insert that avatar into a REPLY for this thread because the file was too large.
David
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You can't be tired of people lying about about theirs and others HP can you?
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06-22-2010, 05:19 PM
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Half-Ass Member
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Join Date: Jun 2005
Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
Posts: 22,005
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Not Ranked
Quote:
Originally Posted by RodKnock
You can't be tired of people lying about about theirs and others HP can you?
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You can tell I'm telling the truth by the fact that I have a hundred or more less than what everybody else claims they've got.
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06-22-2010, 05:32 PM
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Senior Club Cobra Member
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Join Date: Feb 2007
Cobra Make, Engine: KMP 539, a Ton of Aluminum
Posts: 9,591
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Not Ranked
Quote:
Originally Posted by patrickt
You can tell I'm telling the truth by the fact that I have a hundred or more less than what everybody else claims they've got.
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Yep, your lie, er guesstimate, is probably closer than most at the 1 HP per cubic inch figure you quoted.
Last edited by RodKnock; 06-22-2010 at 05:34 PM..
Reason: you're? no your.
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06-22-2010, 05:35 PM
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Half-Ass Member
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Join Date: Jun 2005
Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
Posts: 22,005
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Not Ranked
Quote:
Originally Posted by RodKnock
Yep, you're lie, er guesstimate, is probably closer than most at the 1 HP per cubic inch figure you quoted.
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If you think of the big 454 rat motor from Chevy, and a couple of the big horsepower jobs (Mopar, Ford and others), one HP per cubic inch used to be a very fair benchmark.
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06-22-2010, 05:41 PM
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Senior Club Cobra Member
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Join Date: Feb 2007
Cobra Make, Engine: KMP 539, a Ton of Aluminum
Posts: 9,591
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Not Ranked
Prior to moving up to a bigger engine, I installed a crate Chevy LS6 454/450 engine in my old Corvette. That was a very honest HP figure. A set of AFR heads made it about 500 HP and then I went to crate 540 ci engine that made 600+ HP. All dyno'ed on two different dynos.
I have a hard time believing a stock HP Ford head is equal to a stock HP Chevy head, but what do I know. I'm no expert.
Last edited by RodKnock; 06-22-2010 at 05:50 PM..
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06-22-2010, 05:47 PM
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Senior Club Cobra Member
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Join Date: Feb 2005
Posts: 651
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Not Ranked
Quote:
Originally Posted by RodKnock
You can't be tired of people lying about about theirs and others HP can you?
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It's all entertaining!! If I didn't enjoy it, I wouldn't tune in!
David
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06-22-2010, 07:57 PM
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Senior Club Cobra Member
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Join Date: Jul 2002
Cobra Make, Engine:
Posts: 15,712
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Not Ranked
Rodknock, most of those GM crate motors make their power from a low rpm roller cam, 5,200-5,500 rpm, in that range. Old school tech was based primarily on high rpm, thats a whole different setup for the heads, intake, etc.
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06-22-2010, 08:01 PM
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Senior Club Cobra Member
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Join Date: Feb 2007
Cobra Make, Engine: KMP 539, a Ton of Aluminum
Posts: 9,591
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Not Ranked
Quote:
Originally Posted by Excaliber
Rodknock, most of those GM crate motors make their power from a low rpm roller cam, 5,200-5,500 rpm, in that range. Old school tech was based primarily on high rpm, thats a whole different setup for the heads, intake, etc.
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The original HP crate engines available from Chevy during the 1970's, 1980's and 1990's, such as the L88, LS6 and LS7 has solid flat tappets installed. Rollers were not widely available then.
Obviously, the newest offerings are now roller cam engines.
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06-22-2010, 08:29 PM
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CC Member
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Join Date: Jul 2008
Location: Driftwood,
TX
Cobra Make, Engine: Contemporary Cobra, 427 side oiler
Posts: 1,850
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Not Ranked
Quote:
Originally Posted by patrickt
You can tell I'm telling the truth by the fact that I have a hundred or more less than what everybody else claims they've got.
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Now THAT is funny.
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