Mirek

Yes I searched....

What is the thinnest graphite gasket on the market ? Is there anything around .043 or so from Felpro or anybody ?
I do not understand gasket bore but this will be a stock shortblock w/ .024 milled heads so "stock" gasket bore I suppose.

My block is finally perfectly clean but I cannot use cometics due to a very minor (fingernail size/shape) "indention" into the block (near a bolt hole) where the dealer evidently over tightened the bolt (or something) I have read and heard stories about cometics not sealing correcly unless the block is basically "polished" so I guess they are out.

The heads will never come off (I hope) so I want graphite for piece of mind and I'm using new stock head bolts.
BTW what is that smelly grey paste the dealer used on all my headbolts & should I use it ?

Search = No use.

PREDATOR-Z

GM makes graphite gaskests and MLS (multi layer steel) gaskets (Felpro is MLS).
GM graphite are .052 compressed if I'm not mistaken, I would use one of those for LS1 bore. MLS is .002 thicker (.054)
The thickness will affect your quench which ideally should be around .038>.040 for optimum results as a larger quench will be more prawn to pinging but that can be helped with higher octane or reduced timing or both.

The smelly stuff on bolts is teflon paste which prevent fluids from going up through the bolts (sealant) and helps in securing the bolt and preventing it from loosening up.

Mirek

I thought MLS = Multi Layer Steel. I know GM makes a MLS (which I assume is similar to a Cometics) And yes I am attempting to set my quench (.035-.040) and I have not measured deck height yet but I am just planning ahead based on common deck heigh varience reported.

I will likely need a compressed, composite gasket around .040-.045 or so. Thats where I'm stuck unless GM makes a metal gasket that seals better than cometics with a used block.

Oscar Will

The smelly grey paste we use is anti-seize compound and we slather it all over every fastener that threads into aluminum.

PREDATOR-Z

That is why they call it locktite.

Oscar Will

You don't need any sealer on LS-1 headbolts, they are dry (not open to coolant passages), but anti-seize is a "must" for proper torque.

Mirek

Good info but is there a thinner than stock composite head gasket ?

PREDATOR-Z

True unless the heads are ported then you'll need a "sealant" to prevent oil from seeping through.

Not that I know of, perhaps someone else can chime in.

z-ya

iTrader: (1)

Felpros are .043 compressed for the stock replacment gasket and they are NOT mls
constuction as stated improperly in an above post.

Mirek

As Mr Burns would say "excellent" and thanks for clearing that up z-ya. I was like WTF ? If somebody can chime in with a good expaination of gasket bore I will have hit the tri-fecta.
I am stoked that felpro has that size gasket that is not MLS. I am not taking this bitch back apart (I hope). I had not thought of oil seeping in on ported heads that was a good heads up.
Thanks Fellas

Beast96Z

iTrader: (21)

Gasket bore is the size of the bore hole on the gasket. If you have a stock bore, you want a gasket with a 3.910 gasket bore or some where close to that. Each manufacturer is diffrent. The problem with the fel-pro's is that they have a 4.100 gasket bore. I don't think you want to use that on your stock bore. I've looked up and down myself and couldn't find anything. I'm going with the cometics.

PREDATOR-Z

They are!!

http://www.federal-mogul.com/vgn/ima...20Brochure.pdf

z-ya

iTrader: (1)

The stock replacement gasket from felpro is the permatorque series a composition gasket .043 thick for a 3.9 bore. If you don't believe me call tsp and check they sell
them.I wanted a mls 043 gasket but only cometics were made,way to much money .
Predetor z perhaps you can provide a part mumber for this felpro mls gasket to fit
our application.None of my normal wendors keystone,reliable,sterling,were able to.The part # for the composition gasket is 9284pt.

PREDATOR-Z

Perhaps they make both. .041 for 4.125 bore is MLS, I'll search some more. You might be right on the .043 since they cost 1/3 of the .041 (23 vs 68 $$) which would make sense.

JohnnyStorm

iTrader: (2)

Try this. FelPro 9284pt, stock bore, .43 compressed thickness, $17.71 each!

http://www.pickproparts.com/PartsLis...ategoryID=5412

Mirek

Good news. Thanks

Felpro 9284PT
3.8976 bore
Compressed thickness was not reported
$17

Mirek

Just to clarify....
I cannot actually find confirmation that it is in-fact .043 compressed nor does it actually call the part out as composite/graphite (I am assuming it is due to cost alone). I'll have to figure out who to call I suppose. I would assume that if it is a stock replacement (which it evidently is) it would be .054 compressed.

JohnnyStorm

iTrader: (2)

Mirek,

I got the information here. https://ls1tech.com/forums//showthread.php?t=109201

I will search some more.

Mirek

Thanks man I have searched quite a bit already.....I appreciate it.

Damn thats not .043 or .054 according to those guys.
Somebody has to know this fo' sho' I mean come on is anyone using it ?

I have a bad feeling it is .054-.056 unfortunately.

JohnnyStorm

iTrader: (2)

I ordered mine today. I'll mic em when they come in. I look at this way Mirek, I can spend $44.00 for a set of good quality "Graphite" head gaskets (including shipping). Or I can spend $70.00 for 1 gasket from a company name I never heard of before. I'd rather spend the extra money on the heads I'm getting these gaskets for.