should I use 20w50 synthetic in my 331 Stroker?

I run the 20W-50 down here,you might be better of with 10W-40.

Thicker oil doesnt hurt though.

At some point higher viscosity oil will not be able to get into the tighter clearance areas of the motor. The result would then be increased engine wear. I am not sure what viscosity this would be though. Just throwing it out for discussion.
I would think 20w50 would be ok.

jason

Thicker oil actually has frictional issues over thinner oil, due to the increased viscosity. The extra heat generated mitigates the increased viscosity a little bit. Note that I am a guy who uses 20W-50, so that wasnt a complaint.

If your motor was built on the loose side (one might assume so given your reported idle pressure), the thicker stuff should be ok. If this is a fresh mill, ask your builder/machine guy.

IMHO you cant go too far wrong viscosity-wise with about any oil that's out there, when one is in mildish temps. Once it cools off, obviously is when one has to rethink things.

Just my two cents. Good luck.