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#1
04-06-2009, 07:17 AM
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455 cam choice
I have a 1975 Trans Am 455 4 speed car. The original engine is rebuilt and on the stand , not yet run, sealed up and waiting.I am still working on the rest of the car. It is rebuilt with the original heads, intake and internals as stock , not modified other than forged pistons. The machinist installed a comp cams 9794041 grind which I have found to be an OEM RAIV grind ? The valve springs are the compatible comp cams parts. Is this too much cam for my application and the low compression ratio ?
The car will keep the 3:23 rear gears and the close ratio super T10 the came from factory. I dont mind a lope to the idle, but is this cam a good match for this combo or should I switch it out before I run this engine ? I didnt realize he was going to install this cam or I would have posed this question earlier. I am going to be street driving this car, no racing, wondering if this will work well or not. Any info would be appreciated. Craig |
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#2
04-06-2009, 08:32 AM
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Not a good choice at 7 something to 1 static compression ratio. I like to see closer to 10 to 1 SCR with those cams. The Comp version is NOT a "modified" version with short seat to seat timing, less overlap, etc. It is very close to the original RAIV cam, 308/320, 230/240, 114LSA.....Cliff
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If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
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#3
04-06-2009, 08:36 AM
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Quote:
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#4
04-06-2009, 08:46 AM
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I've never built a 455 with the compression ratio that low, so don't have a specific cam to recomend.
If it were being built here, I'd use something around 215-220 @ .050" intake duration, on a 112 or 114LSA, the Crower 60916 cam comes to mind.....Cliff
__________________
If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
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#5
04-06-2009, 08:52 AM
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Are you sure about the internals/block/heads being "stock"? That term gets abused. The block is stock deck height, the heads haven't been cut, the pistons have the same volume as the stockers, and the compressed thickness of the head gasket is same as stock?
If so, maybe try an XE to up your dynamic c/r. Better yet, do us all a favor and try out one of those Lunati Voodoo cams and let us know how it goes. |
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