Does anyone know the formula to calculating Rod/Stroke Ratio's????

 

you take your rod length, and divide it by your stroke length, so its a dimensionless ratio.

For example, lets say your rod length is 6.625 in, and your stroke is 3.750 in. Your r/s ratio is then 1.766:1.

I've seen different ideal r/s ratios... some say 1.75:1, some say 1.6:1... i dunno which is better. But from what i've read, shorter rods result in higher piston speeds, which means the engine can pump more air. There's a lot of engine theory that goes into this...but right now i'm too lazy to really read up on it and summarize here... i'm getting this info from a high performance pontiac magazine.. my roommate has a GTO. I can read it later and explain it better later if you'd like.