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Old 09-30-2008, 11:54 PM
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curtis73 curtis73 is offline
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Quote:
Originally Posted by ap72
I was looking through some other cam specs, and this cam is actaully smaller than the one used for the STOCK chevy 302 or the 375 horse 350... In fact the more I look at it the more I'm affraid of having too much compression. It says its best suited to around a 2500 stall speed, so it look like this setup will be just the ticket.

anyone care to guess power output? Or perhaps idle vacuum at 900 RPM? I'll be running Gapless rings so that will affect vacuum.
Just because chevy put a combo together stock doesn't make it a good match. My factory LT1 has 10.5:1 compression and a 191/196 cam, and they also do a crate engine with 8.5:1 and a 224/224 cam. You also can't compare those engines you mention. First of all, the 302 was made to rev, so it needed that much cam. It was a race engine that trickled down to the Camaro. The 375hp 350 was gross HP back in a time when gas was darn near free, compression was king, and HP ratings were inflated. If you wanted power (since you didn't have the head and cam ramp technology to get it) you just had to go nuts with duration. You're also comparing two combos that are 40 years old.

If you really want to run this combo, go for it. We are trying to tell you it will suck big time. If you want to believe that it will work fine, that's up to you, but you have a buttload of experience at your disposal on this board and you asked for our help. We're telling you that you have a mismatch.

And no, you won't have too much compression. With that much duration and a 106 LSA, you could run 13:1 on Vortecs and probably not have too much compression. Of course, you'll need 110 octane Also, gapless rings or not, you'll be pulling maybe 8" of vacuum. Power guess? I'd give it 390 hp/375 tq as simulated on Desktop Dyno. The cam won't start making power until 3600 and the heads will be done by 5500; especially with that 106 LSA. That cam is going to really shine at 6500 RPM or higher and stock vortecs won't breathe that high.

Now, contrast that with something more reasonable like a 224/224 duration cam on a 110 LSA you're still going to be making 380 hp, but well over 425 lb-ft of torque, and you'll be able to access that torque all the way from 1500 rpms and up instead of having to rev to 3500 like with the cam you've chosen.

Do what you want, but we're only going to tell you so many times... that cam will suck with your combo.
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