Mr. Luos

iTrader: (9)

I have searched, searched, and searched some more. I see it mentioned enough, but I can't seem to find what exactly it is.

What is it exactly, and what does it affect?

Thanks!

SPANKY LS1

iTrader: (24)

Read through this thread, it explains it pretty well.

Shawn

Mr. Luos

iTrader: (9)

Now I understand, thanks!!!!
I am asking this because I need to find the best gasket for my set-up. But would like to not pay for cometics.
Any other manufacturers have .045 gaskets for a 6.0 bore.

I have -12cc pistons, and it doesn't appear that my pistons come out of the hole at all. Should I contact the builders on this?

Mr. Luos

iTrader: (9)

Man my threads sure find the second page quick.

Do any other manufacturers have a 6.0 bore .045" compressed gasket??? Or is this something I am looking to spend a decent amount on?

Also, out of the hole. Do some motors not even come all the way out??

LS1 Swapper

Why on earth would you want that thick of a head gasket if your pistons don't come out of bore? I am assuming your pistons have valve reliefs?

Mr. Luos

iTrader: (9)

Yes they do.

I am not very versed on the head gaskets. Can you safely run a thinner gasket??? I thought the skinniest was .045", at least popular size wise.

LS1 Swapper

Measure your pistons out of hole(or in hole or nothing) at TDC, you want to run as tight a quench as possible. The thing about an aluminum block is it will expand, on an LSx ~0.008-0.010" when up to temperature. The pistons will be down hole around this much depending on material of the pistons as they expand but not nearly as much vertically as the block. This will increase the total quench from cold. It's fairly safe with valve reliefs to run a very thin head gasket. Cometic makes a 0.027" gasket which would provide plenty of clearance between piston and head if your pistons are not out of hole. Another concern with forged pistons is rock when cold, shouldn't be a problem in your case. The key is measuring everything accurately first.

I always run my engines tight on the quench, works very well. If I posted my cold quench on here most people would think I was smoking crack.

Mr. Luos

iTrader: (9)

I am running iron block for this. Aluminum heads of course. I will have to go out and measure the pistons to the deck. It is a 402 with Mahle -12cc pistons.

That seems like a MIGHTY thin gasket to me.

LS1 Swapper

With an iron block it is, measure and go from there.

Mr. Luos

iTrader: (9)

Best way to measure???

I called the builders today, and they are saying .008" out of the hole. .045" gaskets would be about right then, wouldn't they?

LS1 Swapper

0.040" would be fine as well. It depends on how comfortable you are with the clearance.