It is a 98 l31 motor with the stock vortec heads. Compression should be around 10:1. I have replace the head gaskets 3 times. The first two I was using the arp studs. This last time I used bolts. My next option is to have the heads shaved again but I don't want to dump a bunch more money into this if it's not worth it. Any help please.

 

Have you checked to make sure the block and heads are compltely and perfectly flat?

 

When I had the block machined they did the block and head surface. I took the heads to a different shop to have the heads checked. That shop said they were good(flat and not cracked). This is driving me nuts. Is there a way to check the block and heads myself.

 

Straight edge and a set of feeler guages. And you need an actuall straight edge, not just some piece of metal.

 

What gaskets were you using?

 

I am using the felpro 1010 I believe. I am looking for some feeler gauges and a good straight edge as we speak.

 

Well, using FelPro gaskets isn't helpful to diagnosing this. If you had typed Chinese gaskets, that might have been helpful.
Are you running nitrous or boost?

 

No boost or nitrous. I have just taken off the passenger side head and cleaned it up. I am unable to fit a .0015 feeler under any spot. I know it has been discussed other places but what's a good way to clean surfaces. I have been using a razor blade and lacquer thinner. I will have to wait to pull the other side off until tomorrow.

A little more about the problem... I get it all assembled and then start it up. Once it reaches a good temp, I re-torque the head bolts. I run it again to a warm temp and check. Each time I pull the manifold-to power brake vacuum line and it sprays water. Once I pull the intake manifold there is not an abundance of any fluid in that area.

 

is it all ways the same side? sounds more like a cracked head magnaflux the heads for 30$ id start there

 

I'm not sure how to tell which side it is coming from. Since it is Sunday I am gonna take them in tomorrow.

 

FelPro claims those don't need re-torquing. But the right way to do it is to get it up to temp, then let it cool, not re-torque while the engine is still warm.

 

Also, you need to drain the coolant if you're gonna loosen all the head-bolts before re-torquing any of them. If you don't want to drain the coolant, just do 1 bolt at a time.
If you get any coolant between the gasket and the decks, then re-torque it, the coolant now has a permanent escape path.

 

Compression too much? If you have had heads shaved the compression is going to get higher and higher because your piston gets closer to the heads.

I love cast iron worked heads(I guess I am just a believer about old school stuff)

My dad has had a 8 second car that was a street car and ran spray and boost since 1993 and its got cast heads on it with copper gaskets and never had a problem

Is your temp getting higher then 210?

 

How are you determining the gaskets are blown.When the heads are removed can you tell by looking at the gasket if its blown.Is it blown between cylinders or do you have milky oil on top of heads.I thinks these
guys need to know that info before they can throw you some ideas.Good luck