Strokers run warmer???

My fish had some kind of tall but thin copper radiator in it when it had the 340. After I put in the 416 it ran just as cool with no other changes. That is at cruise power. Stomping on the gas going down the track warmed it up pretty quickly but just driving around I could turn off the elec fan and it would stay at the same 180 degrees.

So based on that you are probably gonna be just fine.