I just had my 383 build and a buddy of mine with a Ls1 recomended cometic gaskets, so i went ahead and choked up 250 bucks. I was thinking hell with i already blew so much money on the motor i might as well get the good gaskets especially its a blower car D1. So when i got the motor back it looked great, but i noticed the little metal rings that keep the gasket toghether on the outside of the gasket by the headers i think 2 on each side. Anyways those little circular whatever you want to call them were smushed in between the head and the block and half of them were still poking out. I asked my buddy if it was ok he said hes ls1 has the same thing its fine. Well i finally got the car tuned so i can drive it, on the way back home last night i noticed my car was smoking from under the hood pretty good, and it smelled defanatly like oil. So i hurried up and got the car back to the shop where i work at, put it up on the lift and discovered the those Tabs from the cometic gaskets were wet with oil. Aperantly the oil was leaking down from the taps and around the tabs down the block, Starter, Tranny bell housing etc. it was a mess when it hit my Muffler y pipe the car looked like it was on fire.
I called the machine shop today and told him what was going on, i thought he would be concerned since he put the motor toghether and was going to tell me to bring it back, but these were his exact words. " oh man you had those cometic gaskets didnt you? yeah sorry man i hate those things, its the return thats leaking" " You cant crush those gaskets, so any kind of scratch on the head or the block even a little one could cause it them to leak" so he went on blopering about how ****ty those gaskets are and i should get a set of Fel Pros and put them on and i wont have another problem. I was mad i spent so much time putting this car toghether. He also told me i could try putting some RTV silicone right where its leaking and that might fix it, so i did. I dosent leak at those places anymore but now it leaks somwhere in the back of the motor. Its not the Manifold cuz i can put my hand back there and feel that its dry but i cant stick my hand all the way down there between the head and the block i cant reach it, neither from the top or the buttom. Especially from the buttom on the drivers side i have a blower oil feed and hooker LTs.
So i guess im going to have to Pull those heads off, i got apr head bolts that are probably 75 miles old, dont want to take a chance reusing the Cometics cuz i belive they are reusable. Does anyone know how long of a job it is to do head gaskets?
sorry this post is so long i had to vent, i havent been able to drive the car with a smile on my face for over 2 months now.

 

If you know what you are doing,about 4 to 6 hours.

 

Um...I built a 386 (destroked 400) for my cousins '70 Camaro with Cometic gaskets. The car runs 10.90 @ 124 MPH, and the heads have been taken off and retorqued 3 times and the Cometics reused everytime...No leaks, no problems.

Frank

 

Cometic gaskets are great. Are you sure you got the correct gasket for the LT1? Where they installed correctly? Don't immediatly blame the product that is obviously good for many others.

 

Yeah...What he said

Frank

 

Dude...You got seriously ripped off. I had Cometic make me a custom set of .057" gaskets for a 400 block, and it only cost me $140 for the set.

Frank

 

I just did Cometics on my 383 LT1 blower motor and have yet to run them, but I noticed the same thing while dry fitting everything the first time. You NEVER should have assembled them with the ring partially covered...slap your buddy. You're supposed to cut it off if it interferes. The order book says this and if you call them, they'll tell you the same thing. The instructions say to verify the position of all holes and make sure nothing interferes. Granted they could include a note about it as well, but they're assuming (bad thing!) that anyone using high end gaskets like that know what they're doing. The fact that the head surfaces have to mate flush should have been a clue. The rivets are there to keep the gasket sandwich assembled during production/shipping, etc., but once you get them and place them on the head, the guide pins hold everything. Hard way to learn though...and I wouldn't blame the product in this case.

It does sound like you got ripped if you paid that much...that's over twice what I paid!

Next time you're in doubt, call the manufacturer or supplier...it's those little things that you question during assembly that'll come back to bite you on the a**...HARD! Good luck with the swap...

 

That happened to one of my motors!! The machine shop did not drill out the rivets and the head never seated to the gasket. It is the engine builders fault! He should know to check interferences!!