COMPRESSED Head Gasket Thicknesses - MLS / Graphite
COMPRESSED Head Gasket Thicknesses - MLS / Graphite Need some clarification on the compressed-thicknesses of various GM-OEM LSx 5.7L head gaskets. Its pretty clear what's available from FelPro, Mr Gasket, or Cometic, but concerning OEM-GM gasket compressed-thicknesses, I'm now confused as hell.
- What is the stock head gasket used on 2002 5.7 LS1s? Graphite or MLS?
- What is the stock head gasket used on all 5.7 LS6 motors?
- What year did GM start using the MLS gaskets on LS1 motors?
- What is the COMPRESSED thickness of the MLS gasket?
- What is the COMPRESSED thickness of the graphite gasket?
There's so much conflicting information in various past threads (many intensive searches), including in our "sticky" above on the Compression-Ratios - for every posting or thread I see stating one thickness, I see another with different info.
PaceParts lists the MLS compressed gasket thickness at .060". Most other threads list the MLS compressed at .054" or .052". And even in our sticky above, there are individual postings that state the MLS has a compressed thickness of .060", .054" and .052". Can't be all three....
Hope to get some definitive clarification on this....! THANK-YOU!
- What is the stock head gasket used on 2002 5.7 LS1s? Graphite or MLS?
- What is the stock head gasket used on all 5.7 LS6 motors?
- What year did GM start using the MLS gaskets on LS1 motors?
- What is the COMPRESSED thickness of the MLS gasket?
- What is the COMPRESSED thickness of the graphite gasket?
There's so much conflicting information in various past threads (many intensive searches), including in our "sticky" above on the Compression-Ratios - for every posting or thread I see stating one thickness, I see another with different info.
PaceParts lists the MLS compressed gasket thickness at .060". Most other threads list the MLS compressed at .054" or .052". And even in our sticky above, there are individual postings that state the MLS has a compressed thickness of .060", .054" and .052". Can't be all three....
Hope to get some definitive clarification on this....! THANK-YOU!
Last edited by 02RedHawk; Jun 20, 2005 at 10:53 AM.
The MLS gasket should have a compressed thickness of .052. The older graphite gasket should be .040 compressed. The graphite gasket was used from 97-98, then GM switched to the MLS from then on (and still uses them for the LS2).
TECH Senior Member
Joined: Mar 2004
Posts: 14,620
Likes: 17
From: BFE
Originally Posted by DrkPhx
The MLS gasket should have a compressed thickness of .052. The older graphite gasket should be .040 compressed. The graphite gasket was used from 97-98, then GM switched to the MLS from then on (and still uses them for the LS2).
Originally Posted by ArcticZ28
I had graphite gaskets on mine and it's a 99.
02RedHawk - I apologize for any confusion. Honestly, I would call a sponsor for the actual compressed thickness of the graphite gasket. I do know it is less than the MLS.
Trending Topics
Originally Posted by DrkPhx
The MLS gasket should have a compressed thickness of .052. The older graphite gasket should be .040 compressed. The graphite gasket was used from 97-98, then GM switched to the MLS from then on (and still uses them for the LS2).
.060" for the MLS
.053" for the graphite
100% sure of that. Have measured them myself.
Graphite was used on 97-01, all LS1's AFAIK. My '01 had graphite. Believe the MLS came out in '02 model years on LS1's.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo Thank-you 1fastWS6.
So, kinda taking this thread now to more of a heads-question, provided that we're all in agreement that the gasket-thicknesses are correct (MLS is .060", Graphite is .053").
Would it be recommended to take .010" off my set of LS6 heads -and- use a .045" Cometic gasket (net reduction of .025"), instead of just milling .025" from the heads and using the stock .060" MLS gasket? (that is, I should then have my quench a bit more optimal, and likely produce more power at the same CR?)
Cam is a 224/224 .581" 114+2, heads and cam going on an '02 Firehawk. No PtV issues with either of my two options above; just looking for which would be "better" - thinner gasket + slight milling, or more milling and stock gasket.
So, kinda taking this thread now to more of a heads-question, provided that we're all in agreement that the gasket-thicknesses are correct (MLS is .060", Graphite is .053").
Would it be recommended to take .010" off my set of LS6 heads -and- use a .045" Cometic gasket (net reduction of .025"), instead of just milling .025" from the heads and using the stock .060" MLS gasket? (that is, I should then have my quench a bit more optimal, and likely produce more power at the same CR?)
Cam is a 224/224 .581" 114+2, heads and cam going on an '02 Firehawk. No PtV issues with either of my two options above; just looking for which would be "better" - thinner gasket + slight milling, or more milling and stock gasket.
Originally Posted by smask04C5
slight mill with thinner gasket will provide better quench. if pistons are .008 out, quench will be near .037 on cometic .045 gasket. good
point taken bigdsz, I should have said that it is more beneficial to mill head a little and go with thinner gasket, rather than milling head more and thicker gasket. quench is determined by gasket thickness, not chamber volume.
