cometics or RJC's ?

[chasmat2316]

has anyone tried both? which one do you like better? I've used cometics in the past, just wondering if anything better? This is for a 109 with gn-1's.

 

[gnxtc2]

If you head or deck surface is not ultra smooth (50 RA) forget about the Cometics.

Billy T.
gnxtc2@aol.com

 

[chasmat2316]

If you head or deck surface is not ultra smooth (50 RA) forget about the Cometics.

Billy T.
gnxtc2@aol.com

Yes the block was decked nice & smooth

 

[Jack Armstrong]

RJC Direct @ www.rjcracing.com

The RJC kit w/o a doubt

directly from Jason & Tom

at RJC Racing the leaders in inovative Buick performance ---

 

[chasmat2316]

someone's had to try both?

 

[buttonfly]

rjc

I just installed the RJC gasket's. This was the first time the heads were off the car. I thought they looked great, fit nice, I was impressed with the ease of installation. Just get some rubber gloves and roll on the GOO! Almost like a kid finger painting!!! J

 

[Mike Licht]

+ 1 for RJC

Mike

 

[chasmat2316]

+ 1 for RJC

Mike

So you give them the nod over the cometic's ?

 

[karst#9]

someone's had to try both?

I think if you had RJC gaskets to start with, you wouldn't have to try both

 

[ds4545]

RJC. We have used both.

 

[bison]

Both work equally well when the prep is done right. You are limited by the number of fasteners, not the gasket type. The RJC is more forgiving than the Cometic as far as prep goes. The black car in my sig has at least 300+ WOT blasts through 3rd gear at 24+psi on a set of RJC's. The car will easily run 130mph in the current configuration. If i had to choose id go with the RJC's.

 

[Mike Licht]

So you give them the nod over the cometic's ?

Yes, we stopped selling the Cometics because of the many complaints of leaks and some "unexplainable" aluminum head failures (torching). I know some guys have used them with no problems but I saw more than I was comfortable with and when I approached Cometic about them they were unresponsive so we stopped selling them. If they would address these issues with me I may reconsider but for now I would say that RJC is a great choice.
Mike

 

[vacuum 6]

Why did RJC offer two different thickness gaskets?

 

[ttypewhite]

I had a set of RJC headgaskets. They worked good no problems. But in the summertime I would use water with some additive. Eventually it rusted in the water jacket of the gasket and started mixing in with the oil. I called Dan at DLS and bought a set of Cometics, and I have used them ever since. When using Cometics, I put the Right Stuff silicone on all head studs, a very lite beed on the block around the coolant jackets and the same with the head. Never had a leak.

 

[chasmat2316]

anyone with Cometic's have them leak between layers?

 

[S2V6RACER]

The problem with cometics is it exposes your machine shop for the $hit work they really do. I had NOTHING but problems with the last guy when we put water in the TSM motor. Come to find out the deck of the block had a big dip in the center. I brought this to his attention and he had no answer and didn't believe me. Anyways, when you have to educate your machinist that's when you know you have a problem. We now use Dan at DLS and he uses the Cometics DRY and we have had no leaks.

Block/head prep are key.

The RJC's look like a great product also, never tried them but I would use them with the same approach as the Cometics. The silicone will bandaid questionable machine work.

 

[8AV8]

Cometics with a thin layer of Hylomar, no leaks.

 

[chasmat2316]

Cometics with a thin layer of Hylomar, no leaks.

did you put hylomar between layers? where did you buy hylomar?

 

[2 SLOW]

It is made by Permatex and should be in most auto parts stores. You can check it out at Permatex - Adhesive & Sealant Solutions...Made for the Professional. I have used it for years with good success. Also known as Blue Hylomar.

 

[Scott Atk]

Are you using Hylomar in a tube? I haven't been able to find it in aerosol for a couple of years.