JET951

I / We find the 3.0L crankcases a stronger case as compared to the 2.5L crankcase , mainly in the area of the Siamese cylinders , much stronger than the free standing ones in the 2.5L

Note } Pats engine breakage , that is a 2.5 crankcase ( Not a 3.0L crankcase ) , modified to a 3+ L capacity & remember this is what racing is all about , Rev it with Max boost until it fails , then next engine , learn from the first in regards to mods that may or may not work

blade7

That's interesting, I wonder what his definition of longevity is. I'd put up with a rebuild every 50k if that was the price of running say 18psi, I wouldn't be happy if it was scrap before 50k though.

Dougs951S

also interested in a "boost vs mean time between rebuilds" curve, if such a thing can be conjectured.

blade7

Stands to reason, along with the raised floor and windage ports. Can you reveal what boost and revs you use on your S2 turbo engine.
I didn't know Patricks engine was originally a 2.5, guessing the problem was crank related somehow, if so probably would have happened whatever block was used.

RajDatta

My understanding is it is actually a k26/8. Would have to check some notes. The turbo RS was a K27/11 if I remember correctly.