racer7088

Having seen so many tests and people trying to imagine there's a big difference and yet there never really is. Reher and Morrison did their test on 10,000 rpm Pro Stock stuff and couldn't even find any real difference. I've read SAE papers on it too vs. real testing and the real results never show any effect. That was GM and Honda that I saw.

I used to be a believer in it till I saw the facts and saw 100K mile engines with "bad" rod ratios and perfect bore and cylinder wear and now I realize the truth. The piston design though is very important depending on the bore etc. and the rings. What I do see quite often are incompetent engine shops blaming their issues on the mystical "bad rod stroke ratio" syndrome all the time.

dankl

iTrader: (1)

Thanks for the information. You put my mind at ease. I was getting a little scared when I saw that earlier post, but you know how it is. So many people post things that are myths or just plain false. Hard to tell which advice to listen to at times.

racer7088

After all the research I did I decided that rod ratio did matter but just not more than about .001 percent it seemed!

valiant65

Ok, my opinion was based on building a turboengine and to that the 40ci difference would easily be compensated with boost. I feel that when building turbocharged engine, its much more important to get the geometry correct than to get as much cylindervolume as possible.

But if Erik says otherwise, I'm ready to belive it...

dankl

iTrader: (1)

I can definitely see something like rod ratio coming into play much more significantly for a boosted application.

racer7088

Valiant, I'd rather have a very strong piston for that turbo engine too so I would also give up some stroke for that as well.