Hey all!

I have been meaning to ask since I had my motor built from the stock 96 to a full PI swap and flat top forged piston set up, if the stock 5w-20 motor oil should be used? I used to use 5w-30 no matter what since the 5w-20 was hit or miss on brand availability. My question is this; should I use a heavier motor oil weight since I am running forged pistons and high compression? I haven't found anyone to really tell me if this aspect of things should change. I only use full synthetics, but would like some input on this or what the rule of thumb is? Thanks.

 

the compression on my mach is 10.1:1 and I use the recommended 5w-20 with no problems. I don't have forged internals so I don't know that aspect of it.

 

It seems to me thus far even with the 5w-30 in it, the forged parts tend to clatter awhile until they are sufficiently warmed up and that may take awhile. I am just hoping to make sure all the right parts stay lubed and to ensure the internals are coated with the right stuff.

 

Personally, I'd say that in the winter, stick w/ th 5W20 but in the summer, go with 5W30. Unless you are doing some serious high rpm racing, than the slightly thicker 5W30 won't affect anything.

 

I'm switching to 5w30 next oil change due to some head noise. And i'm getting close to 93k miles so I want some extra protection.

 

depends on the clearances in your motor. Typically a modular engine is a pretty tightly put together beast if it's gunna live very long between teardowns so the clearances will still be mostly the same as stock... tight. If your ring gaps are set of for NA then you should have no serious issues with 5w-30 oil of any reputable brand. Yes you may have a little bit of oil burn as the pistons swell but we're talking miniscule amounts and done by warm up. I would not be concerned.