Steel shim head gasket question...

[toofastforyou]

I've seen on GNTTYPE.ORG that you can use two steel shim head gaskets stacked together on each head, for some kind of "boost-proof" head gaskets...Is that true? Are there one some you guys who tried this? If yes, who makes steel shim head gaskets for our motors?
Thanks for your replies. 'bye, Claude.

 

[U1ARUNIT]

http://www.rjcracing.com/RJC_Buick_Products/RJC_Head_Gasket_Kit/rjc_head_gasket_kit.html

 

[Nick Micale]

First of all, there is no such thing as a "boost-proof" head gasket. The steel shim head gaskets were used by GM on the '84-5 turbo Buick motors. These hold up very well if installed properly AND re-torqued.

Even using 2 gaskets per head on an '86-7 motor will raise the compression one-half point and may require the intake to be milled for proper fit.

 

[REDS HOT AIR]

mine works great with just one steel shim on each side..

i havent found any downfall to the extra compression..

im running 24# boost on 93 octane and 20 degree timing chip with no knock so i'd say its working fine..

i am getting my manifold milled now to line my ports back up but if nothing is port matched then you could get away without the milling.

if you run comp cams lifters you will have to get shorter pushrods for use with the .042 thinner head gaskets but with my sealed power lifters im still using stock pushrods with no problems.

 

[Steve Wood]

I prefer a single shim gasket. One needs flat decks and straight heads with a shim style gasket of any style. As Nick said above, some engines may require milling for the intake to fit properly.

I would rather the head gasket blow than have the crank depart the bottom, tho.

 

[REDS HOT AIR]

Originally posted by Steve Wood
I would rather the head gasket blow than have the crank depart the bottom, tho.

oh man that takes all the fun out of it..

 

[buickboy]

Cometic multi-layer spring steel. Best out there, bar none.
Mitch

 

[Nick Micale]

Originally posted by buickboy
Cometic multi-layer spring steel. Best out there, bar none.
Mitch

We just used a set of Cometic's on a motor. At $100 apiece not sure they are worth the difference from a GM steel at ~$10 each!

 

[buickboy]

Nick-
First of all if you paid $100 a piece you got ripped off big time. I paid $52 a piece and they are awesome. I got the first two sets in the country, and am still running them with absolute sucess today. I tryed GM steel shims. They are carbon steel with no memory. Cometic are spring steel with Viton coating.
Mitch

 

[Intercooler]

Originally posted by buickboy
Nick-
First of all if you paid $100 a piece you got ripped off big time. I paid $52 a piece and they are awesome. I got the first two sets in the country, and am still running them with absolute sucess today. I tryed GM steel shims. They are carbon steel with no memory. Cometic are spring steel with Viton coating.
Mitch

I will get a pair off you for $104.00 to try if you can send me your info. Thanks!

 

[Nick Micale]

Originally posted by buickboy
Nick-
First of all if you paid $100 a piece you got ripped off big time. I paid $52 a piece and they are awesome. I got the first two sets in the country, and am still running them with absolute sucess today. I tryed GM steel shims. They are carbon steel with no memory. Cometic are spring steel with Viton coating.
Mitch

First, I did not pay for them, the customer did, that is list price.
He wanted a 0.067" thick gasket which costs additional over the normal 0.057" which is closest to stock.

Second, I talked with the owner of Cometic last November at the SEMA show in Las Vegas. After a lengthy discussion, I sent them a "used" turbo gasket so they would consider making them for our motors. I am on dealer pricing with them but most of my customers are not going with them because of the pricing.

 

[toofastforyou]

Reply to Nick...

Nick, after having spoke with Eric Shertz at Dynotech, he explained to me that I'd better stay with stock GM gaskets because they are like some kind of "insurance", or protection. If there were some "boost-proof" gaskets and something went wrong, (like leaning out), without the gasket giving way,then something else more costly would probably let go, like bent connecting rods, cracked block or crankshaft, hole in a piston, etc...Although it's a pain in the a** to blow a head gasket, it's better that blowing the whole engine apart!! So after hearing this advice, I think my wisest choice is to go with stock gaskets again...
'bye, Claude.

 

[azgn]

buickboy, you don't have any info in your signature, so I would be curious to know what your car runs with the Cometics?

 

[REDS HOT AIR]

steel shims will still relieve...

just when you do lift the head and it blows by the gasket your not stuck there.


sounds like bad knock when it blows by them.

 

[buickboy]

Woody-
My car runs 7.1 in the 1/8 on 19 lbs boost with a TE51 turbo, big FM, 50's, and a trans brake with 60 fts at 1.5, launching at 10 lbs. It is not the fastest out there, but that is not the point here. Fact is you can buy the Cometic gaskets through CV products $20 cheaper a piece than you can get them from Cometic. CV will drop ship the gaskets to your door. My only reason for mentioning the gaskets is they work for me and i was trying to help out guys on the board that are looking for an alternative gasket. Use em or not, no skin off my nose.

Mitch

 

[automorph]

Phone number, website for CV Products please

 

[azgn]

mitch

just wondering if you had any "high boost" experience with the cometics....seems like you are making plenty of power with them...always lookin' for a gasket solution...I use the stacked steel and have had good luck so far ( like Nick said, lots of retorque involved tho)

thanks

 

[TClassic]

Give us the Phone Number for CV please!!!!! I did an EXTENSIVE search for these gaskets and came up empty!!!

 

[Intercooler]

It should be on their site: www.cvproducts.com

 

[Nick Micale]

As Red said above, no matter what head gasket you use with stock heads, with too much cylinder pressure, the head will "lift", or deform, and eventially blow out.

The stock gaskets have a graphite coating that gets dispersed throughout the engine in an internal blowout. Lengthy and expensive mess to clean up. Steels are more forgiving and do hold up better. The stock ones "track" when lifted, and it is downhill from there. Steels will conform and do better. This is why I think the stock steels are as good as the Cometics on stock iron heads. Am anxious to see how well the Cometics do under extreme use to justify the higher cost.

As to what Eric said, I do also believe in a top end "safety valve".
You have this when using stock 8-bolt heads no matter which gasket is used. Just that I have a VERY large stack of "used" stock head gaskets, and very few "used" steels. Just my opinion!