You're pretty much limited to copper. The thinnest depends. Maybe .038" but you have to look at overall volume.
How much power are you looking for with a compression change? Very little, right?

 

Cometic has thinner ones, I think they drop down as low as .029 or something. They're a MLS gasket, and require a very smooth finish on the deck and head.

One thing. Lookout for your quench area measurement. I don't know your combo, but with any real rpm I'd think .029 clearance would be a tad small. Unless...your piston is .005-.010 or so in the hole.

Cris

 

There used to be plain ole' steel shim gaskets available that were around 0.020" thick. I was at a swap meet a few years ago and a guy had a stack of around 50 of them for sale.... for $10 or $15 each.

 

On 2006-10-29 13:35, Is1BadFord wrote:
Cometic has thinner ones, I think they drop down as low as .029 or something.

Hmmm...not in their catalog.

N2oMike -- aren't those 'repair' shims that Felpro used to sell ? To be used with regular gaskets? I can't see them sealing properly on their own.

 

Have you tried?
http://www.scegaskets.com/catalog.html

 

Cometic makes MLS gaskets as thin as .027" but you have to call them (440) 354-0777) to place a custom order. Same price as their standard gaskets, and it takes about a week to receive them.

 

any one runnin them

 

This place has a sale on Cometics right now, .027" included
http://www.4secondsflat.com/cometic.html

 

Here, read this thread about the steel shim head gaskets. If you can find them, they are only 0.016" thick uncompressed.

http://www.mustangsandmore.com/ubb/Forum12/HTML/004233.html

 

I think even increasing the compression from 9.5 to 10.5, you only gain about 10 - 20 HP. Not really a great way to increase HP.

How much compression do you intend to gain from a thinner gasket?

 

On 2006-10-29 22:39, allenman85 wrote:

On 2006-10-29 13:35, Is1BadFord wrote:
Cometic has thinner ones, I think they drop down as low as .029 or something.

Hmmm...not in their catalog.

http://www.4secondsflat.com/cometic.html

Cris

Oops, read down after my response, and saw someone already posted this link =).

<font size=-1>[ This Message was edited by: Is1BadFord on 10/31/06 4:02am ]</font>

 

i agonized over gaskets a long time too, what i found was thiniest for least money was MR GASKET .039 MLS like $35.00 from summit,comitic has some half as thin at 3x the price ($150) fel pro is .037 for about $75.00-lol Copper is thinnest at .008 or some crazy **** but they are NOT for daily driver,hope this helps

 

Thanks folks for the replies. This is a simple combination that belongs to a friend of mine. We currently have the engine on a stand to install a pair of World Products Sr cast iron heads and discoverd that the "performance flat top pistons" he bought years ago are really .052 in the hole. He has ran this engine for about six years (mostly street but recently drag only) with stock 58cc heads. It runs fine and realize that it should be freshened, but now with 64cc heads, a large 252* @ 0.050" solid cam, Victor Jr, stall, 4.56's, NO power adders, and lighter car, the compression is going to be lower. Like everyone else, he's on a budget and since it runs well feels no need to take it apart...at least for now. My thought was to install thinner head gaskets for a while until the new short block is complete sometime next year.

I saw on this thread that someone has steel shims gaskets? Where can I get a pair?

I saw the Cometics and am weighing the thought of $120 for a 1/2 a point in compression is worth the price. The car is drag raced only and think that the steel shim may work. If it breaks, it's at the track with a trailer. No harm, we bring it home and go with another gasket.

Thanks...

_________________
Racing Cougars (the other Mustang) for two decades...



<font size=-1>[ This Message was edited by: k718cougar on 11/1/06 12:41am ]</font>

 

Could almost deck the block and be ahead in the money department...

 

Did you call Alex from my link above? Those thin 0.016" gaskets (if he has any) can be a problem with piston/head clearance.... but since your pistons are 0.052" in the hole, I don't guess you'll have any issues.

 

[No message]

 

I'll try him. Thanks

_________________
Racing Cougars (the other Mustang) for two decades...

<font size=-1>[ This Message was edited by: k718cougar on 11/2/06 11:52am ]</font>

 

I tried Alex and he gave me the Cometic web site. I guess he does not have any more steel shims.

Any one out there have a pair that they want to part with?

 

Check on Ebay - they sell anything.
If you do use steel or copper shim gaskets then be sure to put two coats of Metalic copper or silver chrome paint on them (just normal enamel spray can paint). After each coat of paint dries (both sides two coats) put the gaskets in place and bolt them down snug. Torque all the head bolts down to 25, then in ten pound increments to the proper torque.
25, 35, 45, 55, and then the final torque of 70. This makes sure that you get an even seal on the gasket. The metal in the paint acts as a sealer so that the gasket seals better. You can also use "Copper Coat" gasket sealer but it is no better than the metalic paint. I like the "Silver Chrome" because it has a lot of metal in it. Haven't had to do that since they came out with imprinted "perma-torq" gaskets.
Be sure to re-torque after they get warm. Then once more after they cool completely. You should have no problems with shim gaskets if you follow that procedure. The racing guys from Continental told me about that procedure 25 or more years ago. I was having trobles sealing shim gaskets back when there wasn't much else available on engines they quit making before most of you were born. Some times us old guys can teach a little.
Paul

 

Thanks PaulS1950 for a lot of good info.