Thread: New to the BBC scene...need advice

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Pat McCarthy is the acknowledged Big Block Chevy guru on this board and I usually stay out of BBC threads because of his vast knowledge and experience with these motors, but I just got a DynoSim software dyno package a couple of weeks ago and I just love to play with it. Not to say that it is as reliable as what Pat does, because he has dyno'd these motors on the real thing and I haven't.

I had to put your motor together and just see what could be done with it since I haven't done any BBC's.

This is probably a "down the road" build for you because the RPM manifold/850 carb/air cleaner I used probably wouldn't fit under the hood of the Firebird. Well, you could always run without a hood or fashion a remote air filter arrangement.......whatever. This build also uses large tube headers which probably won't find their way into the Firebird engine bay.
What I was trying to do was to build a maximum torque motor that could be used with a stock converter. This cam won't make the most hp, but it will make torque down low, where you can shred the tires on the street. I agree with Pat on the use of a roller cam, but I used a flat tappet hydraulic for this exercise. So here we go....
454BBC
336781 heads
Flat-top pistons, 8.50:1 static compression ratio w/113cc heads.
Edelbrock RPM intake
850 CFM carb of your choice
CompCams XE262, 262/270, 218/224, .504"/.510", 110.

RPM HP TQ
1500 127 443
2000 183 482
2500 231 485
3000 290 508
3500 353 529
4000 404 530
4500 442 516
5000 461 484
5500 428 408
6000 374 327

So, this cam is all done at 5000. Actually, it makes a peak of 465 hp @ 5100. Like I said, there are cams that will make more hp, but I wasn't looking for hp as much as I was low rpm torque that you could use with a stock converter.
Using stock type exhaust manifolds will drop hp to 392 and tq to 477. Using those exhaust manifolds and the low-rise intake manifold you mentioned would drop hp to 360 and tq to 470.

What is really amazing is that the cam I settled on is the same cam you mentioned in post 4. I went through 9 cams to settle on it.