Headgaskets for TT ?
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
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From: Shreveport/Bossier Louisiana
St. Jude Donor '08
Headgaskets for TT ?
I tried a search and couldnt really find what I was looking for.
What is the best headgaskets for a twin turbo setup that will see pretty high boost? Cometic? Stock MLS? Fel-Pro MLS?
What is the best headgaskets for a twin turbo setup that will see pretty high boost? Cometic? Stock MLS? Fel-Pro MLS?
Burning Brakes
Joined: Feb 2002
Posts: 1,137
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From: Texas
I have run as much as 18 PSI without lift / leak issues. I do also have 7/16 inch C5R multiphase head studs from Katech at 95 ft-lbf (Time Sert thread conversion in block to accept 7/16 threads).
I definitely recommend the GM multi-layer steel gasket in the correct bore size for your application (make sure you consider the combustion chamber diameter of your heads in addition to the cylinder bore). I ran the SCE Titan ICS gaskets initially and they leaked water at over 18 PSI (19.4) after several passes. I did run the SCE gaskets with Yamabond #4 around the water courses, heat cycled them with no water, and retorqued the head studs before adding water and making passes, so I think I did everything I could to help them not leak under extreme cylinder pressure.
I definitely recommend the GM multi-layer steel gasket in the correct bore size for your application (make sure you consider the combustion chamber diameter of your heads in addition to the cylinder bore). I ran the SCE Titan ICS gaskets initially and they leaked water at over 18 PSI (19.4) after several passes. I did run the SCE gaskets with Yamabond #4 around the water courses, heat cycled them with no water, and retorqued the head studs before adding water and making passes, so I think I did everything I could to help them not leak under extreme cylinder pressure.
Last edited by R6_C5_CLS55; Feb 6, 2009 at 12:48 PM.
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I'm going to be running cometic gaskets at around 14 PSI on my LS3 short/317 head setup. Hoping not to run into any issues.
Safety Car
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Former Vendor
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I like the Fel-pro's, there a 4 layer with a nice tacky surface, your only supposed to open the package when your ready to use them. The GM MLS are all good too and for the price they just cannot be beat. Just make sure to use the correct sized bore gasket for head your using.
Burning Brakes
Joined: Feb 2002
Posts: 1,137
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From: Texas
My AFR heads are the 225s, which are the larger than the 205s. I did have the heads milled a bit from 72cc down to 67cc to bring the SCR up to 8.9:1 since I am using -30cc Wiseco coated pistons.
Safety Car
Joined: Mar 1999
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From: Toronto, Canada
I was under the impression that with the AFR 225's you need to use a gasket with a minimum bore size of 4.125 according to AFR? This unshrouds the valves and prevents possible detonation.
Burning Brakes
Joined: Feb 2002
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From: Texas
Also, I used a 0.051 inch thick gasket and not a 0.040 inch thick gasket.
We did measure and test fit the gaskets on the heads before installing them.
Last edited by R6_C5_CLS55; Feb 6, 2009 at 09:25 PM.
Tech Contributor
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From: Forney Texas
For the record, I am running 18psi on MLS with ARP studs with no issues.
Former Vendor
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Not saying you're wrong, but it doesn't make any sense to me. The gasket should only be as large or a little larger than the bore. If the bore is 3.905 and you have a 4.125 gasket, the shrouding is going to come from the cylinder walls.
For the record, I am running 18psi on MLS with ARP studs with no issues.
For the record, I am running 18psi on MLS with ARP studs with no issues.
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
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From: Shreveport/Bossier Louisiana
St. Jude Donor '08
Not saying you're wrong, but it doesn't make any sense to me. The gasket should only be as large or a little larger than the bore. If the bore is 3.905 and you have a 4.125 gasket, the shrouding is going to come from the cylinder walls.
For the record, I am running 18psi on MLS with ARP studs with no issues.
For the record, I am running 18psi on MLS with ARP studs with no issues.
Premium Supporting Vendor
Joined: Mar 2001
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From: Knoxville Tennessee
I use stock GM gaskets everything...
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
Likes: 3
From: Shreveport/Bossier Louisiana
St. Jude Donor '08