O-Ring Head

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At what point should a person O-ring a head? How far can someone push one before it's needed?
 
I would say about 70psi for a 24v. But I guess it really depends on timing, nitrous, boost, compression, and head stud size.
 
drive pressure is what will blow your headgasket not boost pressure
 
As said about there are a lot of variables. On a composition head gasket, I would say at about 500hp (with studs), you need to o-ring. On a MLS (stock 3rd gen), with 625+ studs, then at about 800hp, you should look at an o-ring solution. Both of these numbers come from personal experience. :bang

Paul
 
Well I did My CR when I reached the 800hp range. I was having a hard time keeping he head held down. I did my 12 valve just because I have big dreams for it.
 
Drive pressure does not kill head gaskets.

I ran 60# on a 24v with nothing done to it, no studs, no rings, not even tightened bolts.
 
I'm curious about this also. I'm sending my 12v head in next week for work and I'm having o-rings put in for an extra $200
 
I've always wondered why people say drive pressure kills head gaskets. IS that extra 20-30 psi that the piston has to overcome all it takes to blow a gasket?

And is it really boost pressure that kills head gaskets? or is it the substantial rise in cylinder pressure that results from boost pressure? So if that is true then, and I'm theorizing and pulling numbers out of the air here, 40 psi of boost pressure out of an hx35 would be ok even with the 50-60 psi of drive or whatever. But pulling the same amount of boost at a lower drive out of say, a 62/71 or some other bigger turbo would cause it to blow because of the higher cylinder pressures caused by more oxygen in the cylinder. Correct?

Anyone understand what I just tried to say?

On a side note my 62/71 s300 hits 40 psi on a regular basis on stock bolts. Not saying its a good idea. Just saying.
 
I was pushing 50ish on a stock gasket bolts everything and i blew mine, it just started leaking coolant out the front and back, the o-rings in the gasket didn't appear to be blown but obiviously the head had been lifting! I believe it was due to not letting the truck come to full operating temp before beating on it sometimes!

I went back with stock gasket sprayed with copper gasket maker and new stock bolts torqued per "THE" Garmons spec, so we shall see! but so far with more fuel/boost with the same charger it's holding!
 
with my VGT ive pegged the 50psi gauge quite a few times... never touched the head no re-tourque or anything... 248ooo and the rings will go before the head gasket will and thats a fact! ive heard something like this previously... dont quote me but here goes : tourque head if your seeing UP TO 50psi....... new gasket and studs up to ~65~ O-ring, studs, gasket up to 85ish...firering, studs etc should taker on up over 100++psi
 
yoshi470 said:
someone correct me if im wrong but i thought that cylinder pressure and drive pressure were the same thing pretty much? And if high drive pressure doesnt kill the head gasket what does?
Click to expand...

I believe drive press is between the turbine to the cylinder, and of course cylinder press. is gonna be alot higher at times, but the closest measurement is the ratio between boost pressure and drive press. since you can't accurately constant cylinder press. from all the cylinders at once
 
What confuses me is why folks would pull the head to replace a blown gasket and then NOT o-ring the head.

It's cheap insurance to (hopefully) prevent it from happening again.
 
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