I know there is another head gasket for the lt1 besides the stock one that is thicker. I seen a few of the stock ones blow under 12#'s. Does anyone know the part number to the thicker one. I want to stay away from copper head gaskets if possible.


Any help would be great
Thanks George

 

Call Cmotorsports, they have the new LT1 Cometic headgaskets in any thickness you want. They say they are extremely stronger and much better made for N20 and Blown apps. I think they said they are like 140 a set if I remember right. I will be running a set on my new motor. Hope this helps

 

Do you have a link or a number to Cmotorsports? That would be great, but would like to still get the part for the felpros. I heard Internet racing had them, but can seem to find them on there site.



Thanks George

 

FelPro LT1/4 head gasket part number: 1074

 

Thanks Brady, Thats what I was looking for.

George

 

The 1074 is not a stock thickness gasket. It is .039" & the stock unit is roughly .051" This will increase your compression approx .7 points but it is much stronger than the LT1 gasket supplied in the kit. Hope this helps.

 

It was my understanding that the stock gasket is .029 and the 1074 is .039. Thats why they are better than stock cause they have more meat on them. I was told they would drop the compression a tenths not raise it.


George

 

Yeah, Lonnie has a point. That is why I recommended the Cometic's. More pricey yes, but you can get any thickness you want . Hope you find what youre looking for.

 

Just to confirm.... I measured a few used LT1 gaskets & they all measure approx .048-.051. Used gaskets are hard to get a good average as they all distort slightly differently depending on the bolt location.... but based on a gasket bore size of 4.125 which is the listed size in the Fel-Pro catalog there should be approx 2.5cc difference between the 2. The stock LT1 gasket is not in my Fel-Pro catalog. but the 1074 is at 8.7cc. Checked my math & ....it sucked. The correct compression difference should be approx .3 to .4 depending on your piston/deck/bore combination.

As far as thickness goes..... thicker is not particularly better. A thicker gasket has more elasticity to absorb imperfections & therefore seal better. This added thickness also gives a larger area for the combustion pressure to act against & try to blow the gasket out from between the block & heads. (cylinder PSI X gasket area = force against the gasket) The .039" thick seems to be a near ideal compromise as many Fel-Pro gaskets are now this dimension. No gasket will live if the clamping of the bolts is not sufficient & detonation will basically overcome anything you put in there. Hope this helps.

 

I think I see where the confusion is coming into play on my part. I didn't explain enough what I was looking for. The 1074's are .039 like you say, but what i meant by thicker was the area around the water jackets. Thats where the 1074's come into play. I guess Brady understood what i was looking for.


Maybe this will clear up some things.

Thanks for the info though

George

 

The stock LT1 gaskets are .049 compressed. The stock LT1 Impala gaskets are .029 compressed. I'm putting the Impala gaskets on to improve quench. The compression will go up slightly but that's OK too.