Head gaskets
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Head gaskets The stock LS1 bore is 3.898". What bore should the head gaskets be?
I keep finding 4.06" or 4.135"
Anybody familiar with SCE gaskets? Summit racing carries them and I can drive to the Summit store and pick them up. I'll likely be measuring PtoV cleareance prior to final gasket selection. SCE makes LS1 head gaskets in .043" and .032" thickness.
Summit has gaskets from .062" to the aforementioned .032"
I keep finding 4.06" or 4.135"
Anybody familiar with SCE gaskets? Summit racing carries them and I can drive to the Summit store and pick them up. I'll likely be measuring PtoV cleareance prior to final gasket selection. SCE makes LS1 head gaskets in .043" and .032" thickness.
Summit has gaskets from .062" to the aforementioned .032"
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Originally Posted by wallstAL
3.910 is what I use.
SCE's are $129 a set, I beleive that is in the same range as the Cometics.
I'm going to go with 61cc chambers and hope I can clear PtoV with .042" gaskets. If not I can go to thicker gaskets and live with a little less cr.
Futral said take no more than .010" off the heads (F14 cam) so I'll need to see how that equates to 61cc. They're 5.3s, but have had chamber work and new valve seats etc..
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Originally Posted by bigdsz
Do not use 3.910, as per Cometic, it is too close to the flame front. Use 3.970 which is what OEM gaskets are.
Why do all the gasket manufacurers sell 4.06" for stock LS1 applications? That's what shows up on Fel-Pro GMPerf and SCE....
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Or to muddy up the water evern more...
"Fel-Pro Performance Head Gaskets
Head Gasket, Composition Type, 4.135 in. Bore, .041 in. Compressed Thickness, Chevy, 5.7L, LS1, Each
Mr. Gasket Ultra-Seal Head Gaskets
Head Gasket, Ultra Seal, 4.000 in. Bore, .042 in. Compressed Thickness, Chevy, LS1, Right Side, Each
SCE Pro Copper Head Gaskets
Head Gaskets, Copper, 4.000 in. Bore, .032 in. Compressed Thickness, Chevy, 5.7L, LS1, Pair"
Summit Racing has no gaskets for an LS1 under 4.00"
"Fel-Pro Performance Head Gaskets
Head Gasket, Composition Type, 4.135 in. Bore, .041 in. Compressed Thickness, Chevy, 5.7L, LS1, Each
Mr. Gasket Ultra-Seal Head Gaskets
Head Gasket, Ultra Seal, 4.000 in. Bore, .042 in. Compressed Thickness, Chevy, LS1, Right Side, Each
SCE Pro Copper Head Gaskets
Head Gaskets, Copper, 4.000 in. Bore, .032 in. Compressed Thickness, Chevy, 5.7L, LS1, Pair"
Summit Racing has no gaskets for an LS1 under 4.00"
Last edited by ssheets; Jan 17, 2008 at 02:03 PM.
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Verdad Gallardo Maybe that gasket fits the 5.3L bore, all I know is Cometic told me a couple of months ago and a friend of mine last week DO NOT use the 3.910 use 3.970 on a 5.7L. The other larger gaskets they offer must be for a sleeved or bored iron block.FelPro makes gaskets for our cars they just came out with a MLS and they have had a composite but I have heard of sealing problems with it.
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From: BFE
What I find weird in this is that no one offers a 3.970 gasket.
There is a list of Cometics from Thunder Racing and no mention of so.
use this one 119-H1294045S .045 3.905 bore and shoot up to 200 dry. I've removed them 2 times and there was no issue with ring burns.
There is a list of Cometics from Thunder Racing and no mention of so.
Part # Product Price My Cart Wish List
119-C5475 Cometic MLS Cylinder Head Gasket, LS1 Engine, .051 thickness, 3.910 bore (sold individually) $84.99 Buy Wish
119-C5476 Cometic MLS Cylinder Head Gasket, LS1 Engine, .054 thickness, 3.980 bore (sold individually) $84.99 Buy Wish
119-C5317 Cometic MLS Cylinder Head Gasket, LS1 Engine, .051 thickness, 4.130 bore (sold individually) $84.99 Buy Wish
119-C5318 Cometic MLS Cylinder Head Gasket, LS1 Engine, .054 thickness, 4.160 bore (sold individually) $84.99 Buy Wish
119-C5319 Cometic MLS Cylinder Head Gasket, LS1 Engine, .054 thickness, 4.190 bore (sold individually) $84.99 Buy Wish
119-H1294045S Cometic MLS Cylinder Head Gasket, LS1 Engine, .045 thickness, 3.905 bore (sold individually) $84.99 Buy Wish
119-H1518SP1051S Cometic MLS Cylinder Head Gasket, LS1 Engine, .051 thickness, 4.100 bore (sold individually) $89.99 Buy Wish
119-H1518SP1078S Cometic MLS Cylinder Head Gasket, LS1 Engine, .074 thickness, 4.100 bore (sold individually) $134.99 Buy Wish
119-C5475 Cometic MLS Cylinder Head Gasket, LS1 Engine, .051 thickness, 3.910 bore (sold individually) $84.99 Buy Wish
119-C5476 Cometic MLS Cylinder Head Gasket, LS1 Engine, .054 thickness, 3.980 bore (sold individually) $84.99 Buy Wish
119-C5317 Cometic MLS Cylinder Head Gasket, LS1 Engine, .051 thickness, 4.130 bore (sold individually) $84.99 Buy Wish
119-C5318 Cometic MLS Cylinder Head Gasket, LS1 Engine, .054 thickness, 4.160 bore (sold individually) $84.99 Buy Wish
119-C5319 Cometic MLS Cylinder Head Gasket, LS1 Engine, .054 thickness, 4.190 bore (sold individually) $84.99 Buy Wish
119-H1294045S Cometic MLS Cylinder Head Gasket, LS1 Engine, .045 thickness, 3.905 bore (sold individually) $84.99 Buy Wish
119-H1518SP1051S Cometic MLS Cylinder Head Gasket, LS1 Engine, .051 thickness, 4.100 bore (sold individually) $89.99 Buy Wish
119-H1518SP1078S Cometic MLS Cylinder Head Gasket, LS1 Engine, .074 thickness, 4.100 bore (sold individually) $134.99 Buy Wish
The Cometic MLS .045 3.970 is a very popular gasket, the only problem is that it's almost impossible to find. As fast as Cometic makes them they are sold . The main reason is that optimum quench is .035-.040. With our pistons out of the hole .006-.007, that makes the quench .038-.039.
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From: BFE
Originally Posted by bigdsz
The Cometic MLS .045 3.970 is a very popular gasket, the only problem is that it's almost impossible to find. As fast as Cometic makes them they are sold . The main reason is that optimum quench is .035-.040. With our pistons out of the hole .006-.007, that makes the quench .038-.039.
BTW I had a 99 block that was .005 PTDH, my 01 is .007.
But I still have had mine for over a year and 40+ passes at the track (all on nitrous) and no issues on ring burn.
You are very lucky to have found .045's period. I must have called 30 companies, no good, at best a 3-4 week wait. Unfortunately I ended up with the OEM .053 composites. Next time I will have the gaskets on hand before the engine gets torn down. Also now that FelPro is making MLS gaskets Cometic will no longer have a lock on the market, maybe we'll see some price reductions.
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Don't you have anything better to do than reply to dead threads yourself?
LOL, apparently I don't either! Peace!
I wouldn't have replied to it but he has been bringing up a bunch of old threads and it's a little irritating when he's doing it for no apparent reason.