Ive done it now!!!

[95 GA/TA]

I have been trying different pulleys on my supercharger to see what kind of boost it would produce.Ive been getting around 5-6psi with no problems.I replaced some intake tubing and wow on my first pull i saw 10psi and then the bad stuff happened.The car started running rough and smelled like antifreeze.I limped home and it appears i have blew a head gasket.I was planning on rebuilding the engine this winter but i guess itll be sooner now.I would appreciate any idea or part suggestions.I want to build the motor to take the boost and have no problems.Me and a friend are capable of doing the engine but i am kinda in the dark on the parts i need to get.If you have any suggestions let me know.

[fastTa]

10 PSI is about the limit on an otherwise stock LT1, and at those limits you will find the weak spots very quickly. It usually ends being the head gaskets on a boosted application.....especially with 137k on them. Are you intercooled? Was that 10 PSI you saw at the manifold?

If you are planning on rebuilding the entire longblock, give someone like Combination Motorsports or Advanced Induction a call. It's gonna all boil down to how much bankroll you can part with.

[JeffM]

Ouch.. Hahaa.. It happens.. Whenever I break something I just replace it with something stronger.

I was tuning my car once when I put the new turbo on, and the wastegate wasn't opening far enough.. I was halfway through third gear when I looked at the boost gauge and saw 35psi.

It was at 35psi for about 5 seconds or so. Car felt pretty fast. hahahaaa
No problems though, these motors can handle overboosting if you don't hold it too long..

I had to go get an external wastegate so I could control the boost. Now I run 21psi daily.

[Mark B]

Im no expert... but you are probably going to want to decrease the compression ratio & get some forged pistons/rods at a mininum. Then of course invest in better head gaskets.

From what I know its the high (10.5/1) compression ratio that really limits how much boost you can throw at these engines.

[95 GA/TA]

Thanks for the replies,i cant say that im surprised that something finally gave.It wasnt a total shocker but i was hoping i might have some freak car that could take the abuse a little longer but its ok.I was seeing 10 psi at manifold,i have only been getting around 5-6 psi boot,i replaced some restrictive tubing and wow,it was fun while it lasted.I am not intercooled,i will probably back it down to about 8 psi on the new motor to relieve stress on the supercharger and reduce belt slippage.I put a 2.25 pulley on the supercharger just to see what itwould do so its turning some high rpms.Im now debating on rebuilding the engine myself or trying to find an engine already built to the spec i need.There is one on ebay,its a 383 stroker that looks pretty good for $4500.00 but it scares me not knowing anything about the builder.If you guys know any resources for complete engines let me know.