best gearing for carbed 3rd gen?

[C4RACER]

HA - well, that makes sense. I was starting to doubt your sanity!!

 

I already know the people I'll be racing will be in the back anyway - regardless of what car I'm in. Looking forward to it.

 

Scott

[hound dog]

http://i43.photobucket.com/albums/e354/Clowdis/cmc305.jpg

Hopefully the above url will take you to a Dyno 2000 image of a 305 Chev small block set up for CMC. I've been sort of lurking on the board and I apologize for not posting more. I've done some HPDE in the MidAtlantic region in an '88 Trans Am with maybe getting into the CMC in the back of my mind. Hope the image comes through.

[bsim]

How's this:

[Lady in Nomex]

Wow! Was this on a Dynojet Dyno? To my knowledge no-one has seen those kinda figs out west with a GM 305 carb spec motor. Carson Scheller's has been one of the the strongest at about high 270s on the tq.

[King Matt1548534716]

Wow! Was this on a Dynojet Dyno?

 

No, it's a computer dyno simulation program. Plus, I think he used the wrong cylinder heads, and the CR seems a bit optimistic.

[GT4Point6]

Is the FWHP ro RWHP?

Looks closer to FWHP IMO so if it is, subtract approx 15% for drivetrain loss with a manual and you'll get about the right TQ but the HP still seems really high.

[fastjohn]

First off that is HP/Torque from the crank. Second those are the wrong valve sizes. Third CMC does not allow porting of heads or high performance manifolds!

[hound dog]

To answer a couple of questions. The horsepower and torque numbers are at the flywheel not the rear wheels. I think you'd lose about 20% of those numbers on the Dyno Jet. The cylinder heads are 305 truck heads which have the 1.94 intake valves (not real sure about 1.6 exhaust valve). At RPM levels under 6000 the valve size doesn't have a huge effect on horsepower anyway. If you deck the block a bit you can adjust the compression ratio upward. CMC rules do allow for an Edelbrock dual plane intake to go with the Holley carb. I put the whole thing together a while back to see what I could maximize from the 305 within the CMC rule book. I am assuming a ground up engine build. What it does show is a max HP at the 5800 to 6000 rpm range as the engine is designed so no need to rev past that point. I bought the Dyno 2000 program several years ago when I was building a 393 engine for my Unique Motorcars Cobra. I won't say that it's very accurate, but most people say it's within about 5%. It does give a great insight into what certain modifications will yield before you spend a lot of bucks to find out.