Am I a wrong for being skeptical about this claim. To have a volumetric efficiency of almost 2 HP to 1 CID without power adders and a 750 CFM carb I would say has got to be too good to be true.
I don't know what CFM they are restricted to in NASCAR, but they use no power adders and get over 800HP from a SBC.
my friends 76 corvette ran in the high 9's with a 377sbc,750 holley,no power adders,2 bolt block,pump gas,& independant rear. now runs 9.0's,with 434sbc,850 holley,no power adders,pump gas on the street,chev 12 bolt gears in 9" housing. the first engine was flat 700 hp from 3500-8000rpm. he builds pump gas pro street engines & is a holley wizard.
To have a volumetric efficiency of almost 2 HP to 1 CID HP rating is not volumetric efficiency. VE is a measurement of how effectively the engine fills the cylinders with air. http://en.wikipedia.org/wiki/Volumetric_efficiency "The limit for naturally-aspirated engines is about 120%, these engines are typically of a DOHC layout with four valves per cylinder." also, Offenhauser's were turning 3 HP per cube in their more advanced forms: http://en.wikipedia.org/wiki/Offenhauser how high are they twisting that 363?
if i remember right,my friends 377 had a VE of 113%.like he told me,just because a carb is rated at 750cfm,it doesn't stop flowing when it reaches that volume. one of the best tips he gave me was when i was going to buy a set of headers,he made me listen to a cassette tape from "headers by Ed" about header design.mostly tube size & length. bigger is not always better.
But Chevy horses are smaller.....:laugh: You see it on the Pass Time show. Guy will claim 1000 hp in 3000 lb car and run 9.60s when another with 700 hp will run quicker. and both hooked up. But yes, there are some killer small blocks out there......
An unlimited budget is the key. Look at Formula 1 racing to verify this. These motors are by rule restricted to 2.4 Liters (146 Cu. In. naturally aspirated) and make somewhere around 700 HP. And this is with unleaded gasoline. Thats over 4.5 horses per cubic inch. These teams spend millions of dollars on engine development. FIA the sanctioning body capped the RPM limit at 19,000 after the 2006 season. Prior to that, some of them were spinning 21,000. The higher you twist a motor the more power it can make assuming you can get enough air through it. I cant afford to build a motor that will spin 7000 let alone 21,000 RPM. A 750 CFM carb should be adequate to feed a 363 cu. in. motor at 85% v.e. to 8400 RPM. Just keep in mind, as kenm455 stated, the CFM rating of a carb is not an absolute number. Most mechanical secondary carbs will out flow their CFM rating. Given the right combination of parts 700 horses from 363 cubes even at 8000 RPM is quite possible.
Yep, my buddy's old-school Dart Buick headed 377 does 7-hundred something hp and it is far from super high-tech. Some of today's bolt-on CNC'd 23* heads flow almost as much air from a way way smaller intake port. It does 9-hundred something hp with a 200-shot and starts leaking coolant as the heads are beginning to lift. 9.80's so far in a very un-sorted-out street legal 66 Nova. It starts pulling about 6000 rpm. He paid $5,000 for this engine used; makes me wonder why I have spent so much on Buicks.
