Big windows, little windows?

[pdxjim]

I will be buying pistons for my RD350LC soonish.

As far as I can tell, I can get little round window RD style or big oval window RZ style to fit.

Is there a performance difference between the two?

[Organicjedi]

I was always under the impression to get the bigger windows for better flow. I have modded RZ pistons in my 400 for that reason.

[~JM~]

I may be wrong, but I see no downside to the larger openings.

[m in sc]

well, as the piston moves down and the reed is closed, that's where the boost port flow moves through, aside from the intake pull, so, it definitely doesn't hurt.

[SUPERTUNE]

All my RD engines I build and tune, all run better on the RZ/Banshee
pistons.
Chuck