Cam Spec Differences.. EFI vs Carb'd
09-03-2007, 03:29 PM
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Cam Spec Differences.. EFI vs Carb'd Opinions everyone!! I'm going to try a carb/distributor setup this time around and wanted to hear some opinions on what I should do camshaft wise.. Will the current cam work just as good or will there be some power left on the table because of the change from EFI to Carb?? I would think that cam choices would be a little more abundant now..
Old Combo - Nitrous Fed 408 w/ 12:1cr, AFR Heads, GMPP Intake, 1500cfm Accel TB, 42lb Injectors, Tuned via HP Tuners.. Currently has a Comp XER 246/254 .613/.613 113+3..
New Combo - Still Nitrous Fed, 408 w/ 12:1cr, AFR Heads, Ported Victor Jr Intake, Holley 950 HP Carb or possibly bigger, MSD Distibutor & Ignition, etc..
I'm thinking just a hair more lift at around .625 or so and duration in the 250's with something like 10 degrees of split in the duration.. Which could be totally wrong, but I know the 10 degree split will love nitrous. But, the lobe seperation is where I'm kinda confused.. Any advice??
Old Combo - Nitrous Fed 408 w/ 12:1cr, AFR Heads, GMPP Intake, 1500cfm Accel TB, 42lb Injectors, Tuned via HP Tuners.. Currently has a Comp XER 246/254 .613/.613 113+3..
New Combo - Still Nitrous Fed, 408 w/ 12:1cr, AFR Heads, Ported Victor Jr Intake, Holley 950 HP Carb or possibly bigger, MSD Distibutor & Ignition, etc..
I'm thinking just a hair more lift at around .625 or so and duration in the 250's with something like 10 degrees of split in the duration.. Which could be totally wrong, but I know the 10 degree split will love nitrous. But, the lobe seperation is where I'm kinda confused.. Any advice??
09-03-2007, 07:48 PM
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I am by no means a cam expert, but it has always been my understanding that a carb would like much less LSA and more overlap. That said the spray dictates similar LSA's to EFI style cams so not really sure. I would think a LSA of about 110 might perform better with a carb than your 113, maybe even tighter if you were not spraying.
09-03-2007, 09:38 PM
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Originally Posted by BOWTIE
I am by no means a cam expert, but it has always been my understanding that a carb would like much less LSA and more overlap. That said the spray dictates similar LSA's to EFI style cams so not really sure. I would think a LSA of about 110 might perform better with a carb than your 113, maybe even tighter if you were not spraying.
09-03-2007, 11:18 PM
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I was under the impression that with the exception of idle tuning, the cam requirements had more to do with the actual intake manifold, rather than FI or carb. What I mean is the difference between an ls6 and a victor would be huge regardless of how the fuel gets there. OTOH, the difference between a victor and gmmg should be minor. If I'm wrong I would love to know why, as good info is always handy to have.
09-03-2007, 11:38 PM
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Originally Posted by gametech
I was under the impression that with the exception of idle tuning, the cam requirements had more to do with the actual intake manifold, rather than FI or carb. What I mean is the difference between an ls6 and a victor would be huge regardless of how the fuel gets there. OTOH, the difference between a victor and gmmg should be minor. If I'm wrong I would love to know why, as good info is always handy to have.
