[Walt Fricke]

Guys - the question is this: is it possible to get 225 RWHP from a small port SC engine, otherwise unmodified from stock except for the best race exhaust (no cats, no mufflers), but with the best intake/engine management system on top of that 35mm port?

There are dyno sheets out there which support the ability of the big port 3.0s (39mm port), with CIS, to achieve those RWHP figures. Same with the 3.2s with the DME chipped.

Could the best intake and management system above the small port reach that figure?

If the VE needed to do that is pretty clearly unattainable, best to look elsewhere. I have no flow bench numbers on those heads, but the port is going to limit the flow, is it not? Yes, some guesswork, but I am pretty sure there is enough expertise out there to support this kind of exercise. It may well be that only forced induction could get enough air through that small a port to the to that kind of HP.

Fiddling with somewhat rule of thumb VE calculators suggests that an air flow per cylinder of 33 grams of air per second might get you to that HP number at a VE of 100%. Alternatively, at 100% VE a cylinder could flow 25 liters per second at 6,000 RPM, which would be 32.3g at standard pressure (fairly close to the other estimate).

Are these figures ball park? Could the best intake system (least restriction, like barrel or slide valve, or any other) achieve that? Assumes you could buy one for a 34mm port (remember, no machining of heads). Would that small port head with just some sort of tube on the port flow that? Or some amount which, supplemented with some draw from the extractor exhaust, would achieve those numbers? Stock valves, stock lift, stock cam profile, etc?

HP/wt tends to be popular, but has its issues as well. Combining dynos with parts/engine specifications works best if you are serious about keeping the performance of the engine within a limit. CR and cams can be measured on site, and occasional checking with a dyno on site should keep the playing field level so we can all measure our skills against each other.