Thread: Chevy 400

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Hi

I`ve got a mate with a 400 chevy with a weiland 6/71 blower on it , just had the bottom end rebult and low comprssion piston fitted , but it keeps blowing head gaskets , then at the weekend at a drag meeting did them again when we stripped it out found 3 of the studs into the block were cracked into the bores, is this a common fault or to do with the blower
He has been told to O ring the new block next time instead of head gaskets
is theis a good idea ??

Craig

I assume there's steam holes drilled?

There are, in my opinion, several things that will cause blown gaskets on a supercharged motor, the deck and/or heads are not parallel, running too much boost for the gasket used and letting the motor run in detonation. You'll have to determine what's happening to fix it. If the motor has been detonating, it's gonna pound the bearings out of it, bend some rods and maybe break some pistons too.

Originally Posted by speedemon

Hi

I`ve got a mate with a 400 chevy with a weiland 6/71 blower on it , just had the bottom end rebult and low comprssion piston fitted , but it keeps blowing head gaskets , then at the weekend at a drag meeting did them again when we stripped it out found 3 of the studs into the block were cracked into the bores, is this a common fault or to do with the blower
He has been told to O ring the new block next time instead of head gaskets
is theis a good idea ??

Craig

I run 400s and I have never had a stud crack into the bores. My guess is that you will need a new block. As for gaskets, tell your buddy to try Cometic gaskets. They can be ordered any thickness and can be reused numerous times. They are even better than o-ringing the block or head.