Fire ring Vs. O-ring Vs. Stock

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sstockton

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I'm trying to decide which route I need to go to best protect my engine (24v). The truck isn't going to be used for sled pulling and will probably only see the track once or twice just to see what it'll do. I will be running twins, using an ht3b and a stocker up top maybe a 35/40 hybrid later if that gets too hot. I will also be running Mach 5 injectors and a drag comp.

So I guess the question is, would a stock or Marine Gasket with Head studs hold up fine for what I'm doing or should I o-ring or fire ring the head?

What is the difference between o-ringing and fire ringing? IRRC I've heard some people say that they had to replace their fire rings almost yearly. Thats not something that I really want to be doing.
Sean
 
You should either O-ring or fire-ring the head or block. Personally I prefer O-rings on everything but extreme performance engines that are only going to see the track. The O-rings will hold 80+ psi boost and seem to last longer

The difference is with an O-ring a groove is cut into the block or head and a SS wire is inserted which protrudes about .010. This wire smashes into the OEM gasket fire-ring providing extra clamp force on gasket fire-ring. A fire ring is basically the same but bigger, uses a gasket with no fire-ring as the wire/ring provides the seal.
 
You're looking at good, better, best. O-ring uses a wire that protrudes into the stock fire ring in the head gasket for better clamping. Fire rings completely replace the stock fire ring in the head gasket and require a larger groove cut into the head. Both can be done to the head only, block only and fire rings can be both head and block. I have fire rings and haven't had an issue as of yet with them holding some aggressive timing, fuel and boost.

IMHO if you're looking at keeping it down around 50lbs of boost, o-rings should do you fine.
 
Well, I've been talking to JR adkins about a 24v head cut for fire rings that he has, that he said pressure tested, and was thinking of going that route. Or having my stock head cut for o-rings. So I was just trying to figure out what option would work best for me. Are the gaskets for fire rings anymore expensive than a stock style gasket? Sounds like the fire rings might not be a bad way to go though. Just to be on the safe side, Its worth it to do it right IMO.
Sean
 
sstockton said:
So I guess the question is, would a stock or Marine Gasket with Head studs hold up fine for what I'm doing or should I o-ring or fire ring the head?
Click to expand...

I know Timmy Barber ran a set of 35/3b twins for a couple years with a setup simular to yours on stock head bolts, then another year with studs before pulling the head. I don't think he's on this forum, but his webpage is TRE diesel. I'd say stud it for now then pull the head if/when you have hg problems. At least thats my plan =P
 
O-ring on anything under 80 psi here also, haven't had an issue yet! Call it 80K miles now!

Jim
 
I had been thinking of just studding it for now, and putting in a blow off valve, to try and keep boost down a bit. However, my main concern was that in the future when I want to o-ring it or whatever, you have to pull the motor to pull the head if you have studs in right?

Which brings me to my next question. Once studs are installed, can you remove them and reuse them? Or do they stretch too much. Just thinking that then I could remove the studs and pull the head without pulling the motor. I know reusing head bolts is a bad idea, and I never do that, I'm just not sure about the studs.
Sean
 
sstockton said:
I had been thinking of just studding it for now, and putting in a blow off valve, to try and keep boost down a bit. However, my main concern was that in the future when I want to o-ring it or whatever, you have to pull the motor to pull the head if you have studs in right?
Click to expand...

Negative, allen wrench in the end of the stud and out they come...

sstockton said:
Which brings me to my next question. Once studs are installed, can you remove them and reuse them? Or do they stretch too much. Just thinking that then I could remove the studs and pull the head without pulling the motor. I know reusing head bolts is a bad idea, and I never do that, I'm just not sure about the studs.
Sean
Click to expand...

Yes, you can re-use them.
 
Well thats good news. I might stud it for now, see what my boost pressure looks like and then go to o-rings later.

Like I said, most of my driving is really mellow anyways. It sounds like o-rings are the direction I should go, but I'll probably do that a couple months down the road. First I've gotta spring for a tranny.
Sean
 
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