Still undecided about a cam for my 5.7

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kenh

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So all this is getting way over my head. lol I guess a call to my cam vendor of choice will be in order. We also have a race engine builder local to me but that may not be the best choice for an opinion when I want to be on the other end of the spectrum.

Ken
 

L31MaxExpress

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In an LT1 engine, the cam is never not on. The blue line is the last time I did an unrestricted pull, the other 2 are me getting down to 260whp with restrictor plates in my Camaro.

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I could see a different intake maybe giving more torque in the 3000-4000 range. Since adding additional crankcase breathing I've had to further restrict. It's closer to 299 now.

A dual plane manifold will add about 30 ft/lbs of torque in the low-midrange compared to the LT1 manifold.
 

L31MaxExpress

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Lt4 is usually 110 so it has the bottom end pull with the much larger heads and intake. No two timing sets will degree the same.
While that maybe true on the LT4 Hotcam with its ideal ICL of 109, the factory LT4 is 115 LSA and installed on a 116 ICL. Have degreed several of them. GM installed the cam retarded so that they did not have to install an EGR valve.
 

L31MaxExpress

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I would put a vortec truck cam over tbi any day. They are way better response and make more hp on dyno not to mention they dont go flat or kill lifters due to crap oil like tbi. The roller lifters is where the hp, durabilty and the faster responce comes from
I have had a roller lifter in a GM crate engine fail and wiper the cam in less than 30K. I would personally run the TBI cam over the Vortec. The TBI cam is the same cam that came in the old 300 hp 350 and about every other base ening from the 283 on. On a factory engine the roller lifters added 5 hp per GMs ratings and that seems about right on the tame factory cam grinds. I never liked the factory vortec cam. The Vortec and Dodge Magnum V8s like the 360 had the same issue. They acceleration slowed down on the highway when you floored them and ran them to the stock 5000 rpm shiftpoints.
 
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badco

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I used to have all the dyno sheets for cam tests and the tear down sheets from several lt1s from deck height to what factory cam was in it. If they still around ill double check but hey everyone already knows the information so not much useful information anyway
 
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