: High Performance Head Gaskets?



ThrowSumD'sONDatBiSH
10-09-07, 02:34 PM
Does anyone know where to get high performance head gaskets for a northstar deville like permatorque or something like that? Has anyone ever heard of high performance head gaskets that are readily available for northstars? Thanks

AJxtcman
10-09-07, 08:53 PM
Does anyone know where to get high performance head gaskets for a northstar deville like permatorque or something like that? Has anyone ever heard of high performance head gaskets that are readily available for northstars? Thanks

The gasket is not the problem. It is the block.

Submariner409
10-09-07, 09:29 PM
:hide:

1. No
2. No

dkozloski
10-09-07, 09:47 PM
According to the GM Powertrain engineer, the gasket is a composition and metal sandwich. When the coolant is not serviced properly the metal in the middle of the sandwich corrodes away and the rest of the gasket quickly follows. Coolant leaks into the chambers surrounding the headbolts and the threads corrode and let go. Control of cooling during the casting process has always been problematic with the diecasting process resulting in localized heat treatment defects in the casting. There is a heat treatment defect in aluminum castings called intergranular corrosion that progresses very rapidly in the presence of moisture and results in the aluminum having a consistancy that resembles wet cardboard. The corroded bolt threads pull out of the aluminum and the gasket blows. The problem starts with the coolant degrading but it's exacerbated by the intergranular corrosion of the bolt threads that follows. Now you know the rest of the story.

AJxtcman
10-09-07, 10:07 PM
According to the GM Powertrain engineer, the gasket is a composition and metal sandwich. When the coolant is not serviced properly the metal in the middle of the sandwich corrodes away and the rest of the gasket quickly follows. Coolant leaks into the chambers surrounding the headbolts and the threads corrode and let go. Control of cooling during the casting process has always been problematic with the diecasting process resulting in localized heat treatment defects in the casting. There is a heat treatment defect in aluminum castings called intergranular corrosion that progresses very rapidly in the presence of moisture and results in the aluminum having a consistancy that resembles wet cardboard. The corroded bolt threads pull out of the aluminum and the gasket blows. The problem starts with the coolant degrading but it's exacerbated by the intergranular corrosion of the bolt threads that follows. Now you know the rest of the story.

I have a box with your name on it.
Long story, but I will mail it out some day.

97Concours1
10-12-07, 01:01 AM
I got Fel-Pro PermaTorque head gaskets for the Northstar from RockAuto.com. The part numbers are 26150 PT(left) and 26151 PT(right). They were about $19 each. They don't look like anything fancy, just normal head gaskets. Every other gasket on the engine is an engineering marvel though - and very expensive.

As was explained previously, maintaining the clamp load on the gasket is the real problem. The aluminum head bolt threads in the block let go, which causes a release of the clamp load on the head gasket. Then it leaks. If you are going to do a head gasket repair, do lots of research on inserts for the head bolts. Good Luck.

med
10-12-07, 01:01 PM
What is the compression thickness (i.e., after torquing down the heads) on those Fel-Pro 2615x's anyway? Does anyone know the thickness of the standard GM head gasket set or its compressed thickness? Just wondering.

ThrowSumD'sONDatBiSH
10-12-07, 01:26 PM
What are the best time serts to use the regular ones? Where do I find them? Do I need all new bolts too? Is there a whole kit somewhere with the whole kit with timesert and headbolts and everything needed? Thanks for the help.

AJxtcman
10-12-07, 02:58 PM
What is the compression thickness (i.e., after torquing down the heads) on those Fel-Pro 2615x's anyway? Does anyone know the thickness of the standard GM head gasket set or its compressed thickness? Just wondering.

:D dkozloski will in a couple of days.:hmm:

AJxtcman
10-12-07, 03:03 PM
What are the best time serts to use the regular ones? Where do I find them? Do I need all new bolts too? Is there a whole kit somewhere with the whole kit with timesert and headbolts and everything needed? Thanks for the help.

location?

ThrowSumD'sONDatBiSH
10-13-07, 05:42 AM
South Bend, Indiana. Who has the best timesert kit? I think I want felpro w/e they r called because I hear they are the best head gaskets to get.

Submariner409
10-13-07, 03:03 PM
Med...........Probably .035-.040". AJ can mike up a used OEM gasket for comparison. You probably can't gain much if any compression change with the limited number of replacement gasket choices.

kjhansen
10-14-07, 08:47 AM
I had Cometic head gaskets on my '87 Buick Turbo Regal.

http://www.cometic.com/domesticauto.aspx

I ran up to 30psi of boost without a failure. They are extremely reliable and tough, available for the Northstar and extremely expensive ($113 EACH). But they'll hold up--probably better than the block/head connection. Get that fixed first.
Keith

97Concours1
10-14-07, 10:24 AM
What are the best time serts to use the regular ones? Where do I find them? Do I need all new bolts too? Is there a whole kit somewhere with the whole kit with timesert and headbolts and everything needed? Thanks for the help.

As you have probably noticed, there are a lot of different opinions on Timeserts and inserts in general. Some only put inserts in the threads that are bad, some do all 20 just in case. Some use the brand name Timesert with success, some use Norm's inserts with success. I used Norm's inserts because they have longer course threads that bite into more of the aluminum. And I did all 20 holes. Norm's tooling for re-threading the block is not as fancy as the Timesert tooling, but it seems to work ok. The Norm's kit is on Ebay for about $350. You can usually find a used Timesert kit on Ebay too if you want to go that way.

Replacing the head bolts is also a debate. There are too many unknowns about using the old bolts, so just buy new ones. You can get them at RockAuto along with the head gaskets.

I haven't seen a kit with everything included. That would be nice though.

ThrowSumD'sONDatBiSH
10-21-07, 09:31 PM
thanks for the help guys... my location is south bend indiana

dkozloski
10-21-07, 11:30 PM
What is the compression thickness (i.e., after torquing down the heads) on those Fel-Pro 2615x's anyway? Does anyone know the thickness of the standard GM head gasket set or its compressed thickness? Just wondering.
Compressed thickness is 0.060-0.065in. depending on whether you're measuring the metalic inserts around the combustion chambers or around the headbolt holes.