Charles.rogers1

Well my procharged '96 has leaking head studs so she got all pulled apart to fix this "small" issue as well as some wiring cleanup, bad frost plug and so on..



When I last redid the motor I had been super rushed and used a regular gasket set and I don't think the regular cardboard style gasket would have held the 11ish pounds for very long.. But that's in the passed and now off the car! my question is what type of gasket would everyone go with, I'm guessing a metal multilayer but if anyone knows a superior brand or tips/tricks like that I would love to hear it !

Joe C

pretty much can't go wrong with fel-pro. not much experience with LT motors, but the application data shows part number 9966PT. personally, I would also install new ARP head bolts while you're at it.

http://fme-cat.com/livedocs/PermaTorque.pdf

Charles.rogers1

Something like https://www.summitracing.com/int/par...1074/overview/ ?? I was looking at the cometic, But for half the price and as good of performance I wont say no haha

Purple92

As far as I know - the MLS Head Gaskets are considered the "best" in terms of handling pressure and in terms of being tolerant of slight surface anomalies... Cometic is the brand that seems to be the "go-to" in MLS style head gaskets. Not the cheapest choice - but you already know that cheap I not the correct answer in all cases.....

If possible - use Head Studs rather than head bolts - they tend to provide more consistent clamping pressure

Obviously - before reassembly - check the heads with a machinists straightedge - if there is even a question about flatness - have the heads lightly cut to ensure they are dead flat.

And cleanliness during assembly goes without saying... The block surface needs to be as nice as you can get it....

Cjunkie

For that engine combo do it right one time. Cosmetic MLS gaskets with ARP head studs. Your done.

ddahlgren

FWIW a B2K turbo L98 used felpro and gm head bolts though the bolts were very close to new. Studs can be a real pain in the butt and bring their own problems at times.

Cjunkie

such as?

ddahlgren

Leaking around the threads 'ant hilling' the block from the shoulder bottoming out and room to get the heads on in some chassis.

Charles.rogers1

so going through looking at that these gaskets and always fine different bores.. im a stock 350 so if I'm not wrong I need a 4.00.. or will any of the lt1 gaskets that pop up work, and just change combustion and so on?

something like these, or is that .125 gonna screw me up ?
https://www.summitracing.com/int/par...1074/overview/

mtwoolford

you won't find, an exact size because once compressed the inner ring of the gasket would be squeezed into the combustion chamber; and amongst other things, become hot and contribute to pre ignition. So...now the question becomes, how much bigger? smaller is better. Most oem style gaskets will be larger by quite a margin, and millions get installed without problems, but a 4.010 for a 4.00 bore, a 4.040 for a 4.030 bore etc, would probably be best.

Go online to the SEC gasket home site, there's a ton of good information there.

Charles.rogers1

Alright thanks! Cant seem to find any felpro gaskets cross to that size so might be stuck going Cometic!

Cjunkie

I must be lucky because I have never experienced any of that. Maybe it was because ive only head studded Fords?

Purple92

Having coolant "Leak" around the threads is a problem that applies equally to studs or bolts. If the tapped hole in the block is not blind (meaning if the hole goes into the water jacket) - you should be using some thread sealant on the fastener....

As far as the issue with "ant hilling" - my engine guy told me to put the studs in finger tight only - and no Loctite. Most of the time the "head bolt holes" are lightly chamfered during the block "blueprinting" process - so this should NOT be an issue either.

Yes - the need to lift the heads off over the studs can be a real problem - but again - once the nuts on the head studs are removed - the head studs can be unscrewed if needed (most studs - including those made by ARP have small allen head recesses in them to facilitate this)...

dizwiz24

The stock gm ones that you get at dealer are.

at least that what greg at blowerworks told me to use on my procharged 93 with 13 psi max boost.

He said the cometic ones are less forgiving with deck /head prep (im usually pretty **** about stuff but perhaps he has had bad experiences with other customers who arent )


Did use scotch brite to clean block deck, but was extremely careful not to get any runoff into cylinders. Had bores sealed with cardbord discs.

also used thread sealant - cleaned/ chased threadholes first and pulled a knock sensor to drain out the brake parts cleaner i sprayed in the block.

i bought some fel pro lt1 intake manifold gaskets. The ones with the pretty blue outlines, - yeah they didnt line up right.....so thats my opinion in fel pro

BlowerWorks

#1 - Multi Layer Cometic by far the best BUT as dizwiz24 says I do not recommend unless surfaces properly prepped by a competent machine shop - otherwise they will leak ! And that means the BLOCK as well - so unless pulling engine forget MultiLayer SS - i.e. Cometic.
#2 - Studs vs. head bolts - very complicated discussion. In most cases stock GM bolts best as they stretch as needed. Better ARP bolts require new torques values and possibly a re-torque ! BTW - re-torques always better but not always practical. Ideal is an engine that gets a dyno cell test and then a re-torque !!!
#3 - Detroit Black best for normal re-builds as they seal best given rest. FelPro not as good for stock rebuild even with a blower - they just don't seal as well !
#4 - Head studs best if done right but always require a retorque. If Loctite PST 560 used on threads never a leak issue.
All above subject to my failing brain !!!!! lol greg

Charles.rogers1

Detroit black is a brand of head gasket?

BlowerWorks

Used to be the stock GM gasket - today not sure - sorry !

383tpimachine

My cometic MLS are holding 17psi just fine and felpro intake gasket but it is a fancy *** black and blue one in 1206 bore. Seems to be holding hell.
ARP head studs and arp intake bolts (because I like spending money)