i have a 89gt with a 347 stroker with 11/1 compression what weight oil should i be using?? i have been told to use a 50 weight but not sure if that is the right weight.. any help please.... i'm using 30 as of now till i break it in..
It's not necessarily unusual to use a single weight for break-in. However, after that I'd be running a multi-weight. Talk to your builder and get his recommendation. In general you'd want to run a lighter multi-weight (10W-30, etc) so you get quicker flow at start up. The only reason I can think of for thicker oil on a street car is if your builder left the clearances on the large side.