Originally Posted by highboostingm3m5
So...did you ever get an explanation as to why DA chose to sleeve your block? I was told that I am assuming too much with this. It is true that I have never built a V8 motor for boost so I have no technical knowledgen from experience on the subject. That is why I am asking for help from someone who does or had it explained via someone who does.
DA sleaves the blocks out of concern about the ruggedness of the Alusil coated bores to the abuse of high pressure FI. In an early, pre-sleave iteration, they had the Alusil bored out and the cylinders coated with NiCom. NiCom is supposed to have greater temperature and abrasion ruggedness than Alusil. After assembling the engine, it was quickly found that the NiCom lining was not compatible with the high tension rings, and at that point Darten agreed to machine the interlocking sleaves.
Can an S62 with stock internals withstand high boost? Dunno.. seems like a pretty expensive gamble.
The first pix below is Blue Thunder's original engine with a cracked cylinder and broken piston. He since went with sleaves and forged pistons in a new block for his s/c set up. As you may know, there have been several forged
piston failures with higher boost S62 set ups. As a result, DA now uses custom ceramic coated forged pistons, and these have held up well with zero problems.
The second pix below may not be related, but it was the pix I was originally thinking was Blue Thunder's engine. It is from a member who I think had a head gasket failure.
You might drop Bill a PM... I'd bet he'd be happy to share his experiences and thoughts with you... he loves to talk cars!