o-ringing vs. 4.3 gaskets

Slysc

Registered User
I mentioned that I was planning to o-ring my block and someone asked my why I just didn't use the 4.3 late model headgasket instead.

Wha't up with the 4.3 late model headgasket? Is it as good as getting the block o-ringed?

My block is at the machine shop now and I need to decide whether or not to have them cut the o-ring grooves or not.

Any advise?
 
They just have a wire around the cylinder to help it seal. Go with o-ringing, it will hold better. If you want it to hold real good, go with a copper gasket also. Make sure everything else is really strong if you do that, the head gasket is kind of a pressure relief valve and if everything else isn't as strong as that seal then you're gunna start breaking internal parts. Oh and have them cut a receiver groove in the head if you decide to use copper.
 
o-ringing

Is a copper headgasket the same thickness as a stock headgasket? If not, how thick are they? .040"? .030"?, .020"?
If I o-ring the block and use a stock headgasket, do I still need to cut a receiver groove into the heads?

Not worried about my shortblock. It can handle whatever I can muster up. (ARP head and main studs, morana stud girdle, Eagle H-beam rods, custom forged pistons,...)
 
They come in all kinds of thicknesses, including stock. If you have stock gasket types you don't need the receiver. If I were you I would go with the copper because they won't blow no matter what with head studs. One problem with copper is that they tend to weep a little in most cases. What I mean is the water passages don't quite seal as well as a stock material and with the heating up and cooling down the coolant will tend to weep a little. As long as you don't mind a little moisture under your car every once in a while and having to top off your cooling system occasionally then go for it. Some cars don't weep but plan on it if you do the coppers and if it doesn't, good for you. I have a feeling with my setup I could handle a 150 shot of NOS too, maybe someday.
 
I'm using the 4.2 liter multi-layered gaskets and havent had any leaks (coolant or combustion) since re-decking the heads last spring. I'm running 8.2:1 compression and 16-17 pounds of boost.

They do require head studs and a smoothly decked block and heads. The normal milling cutter serations won't seal, they need to be smooth as glass.

I know of two other people with 12 second SCs that filled their oring grooves with JB weld and switched to the 4.2 gaskets.

Here is what the gaskets look like.

headgasket110102.jpg


David
 
Aaron,

I don't know if they are better than oringing the head/block, but I thought I would try them first. If they didn't work I knew I could could always oring the heads without pulling the engine.

The weeping and leaking coolant worried me, not about drips on the ground, but I was afraid of getting coolant into a cylinder and hydralocking it.

I know about 6 guys using these gaskets without problems. Bill McNeil experinced some leaking near the end of last season. I believe his has something to do with how much torque the studs were tightened to.

Chris Wise has had problems with leaking also but we thought they were because head was lifting. Installing 1/2" studs still didn't fix the problem and now we don't think it was the gasket leaking but a cracked head.

So far so good on mine. (knocking on wood)

David
 
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