For those of you building motors with CP pistons check your clearances very carefully. Stock STI head gaskets are not thick enough to give you the recommended piston to head clearance. You need to use something thicker like an .041 or . 051 cometic. don't just check valve clearance check the piston to head clearance. Matt
2618 is fine in a race application. Luckly it was caught before we learned it the hard way. We put Stock STI head gaskets on the bugeye, they replaced .051 cometics. it resulted in virtually zero clearance. Thanks to Ball Engines for catching it before any damage was done. Matt
The only problem that I see is the 2618's are made for most all forced induction/Subaru applications and 4032's for NA/high compression applications, which limits our choices here. Unless I've mis-read the information in the links in the piston thread.
People just have to realize there is no such thing as a 500hp 2.5 liter motor thats not a race motor. If you are over 500hp you are building a race motor and it needs to be re ringed atleast every two years.
You can get 4032 pistons by request. It took some teeth pulling, but I finally got the guys at JE to spec me a 4032 piston for my EA82. Also, RAM Engines, they build SUBARU EA series engines for aircraft, they exclusively use 4032 alloy for all the N/A, Supercharged and Turbo engines.