Quote:
Originally Posted by Billy Nees
For a 350 and larger combo, the only decent one would be this one. It's not without it's "issues" though. It doesn't have a whole bunch of compression and it's the only one of the GM 350s that uses a 2G carb with a 1.18 venturi (same carb as a 305). All of the others have at least the 1.25 venturi 2G.
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OK, I'd like to explore this 2-barrel thing a little more. Assuming that several of you Chevy guys have run 2-barrel combos at some point.
So, what I'd like to zero in on is the power potential, of the smaller carb with the 1.186 venturi vs the larger carb, with the 1.25 venturi.
(1) For those of you who have tried both size carbs on your sbc engine, how much of a power or ET difference did the bigger carb make ?
(2) Lookin at Class Racer Info site, I see that a '73 350 2-barrel sbc is factored at 224hp, in an F or X body, when using factory heads.
http://www.classracerinfo.com/Engine...MAKE=Chevrolet
The '73 350 Pontiac is factored at 210hp.
http://www.classracerinfo.com/Engine...3&MAKE=Pontiac
But, as Billy said, it has less compression & a smaller carb. Just makes sense that this size engine has more power potential, if it has more CR & a bigger carb. Obviously, this is assuming that the 2-barrel carb would be the limiting factor, or "choke point" of a 350 cube engine.
I assume the increased CR & larger carb would definitely give the sbc engine more power potential. I'm guessing that those 2 advantages would more than make up for the 14hp difference. But, how much more ?
I assume there are racers out there running this combo, especially in a Nova. So, for you GM guys who have done a lot of testing & racing, with 2-barrel carbs, please consider these differences & let us know if you think this Pontiac engine has the potential to at least run safely under the car's index. Don't know if the body would make a difference. But we'll assume a Ventura, which would be similar to the Nova for this question.
After all these years, I assume there have been lots of dyno & drag strip testing of different 2-barrel carbs on sbc engines. Any links to any of the results of some of this testing that might show the power potential difference between small & large 2-barrels ?