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Head Gasket - Types - Best Application - O Ring

exXU1

By exXU1,
in Engines & Forced Induction

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exXU1 Mentor

exXU1

Posted
Posted

This thread was started some time ago but read till end for follow up.

I here this expression frequently, some times in different context .

What does this mean exactly please?

How do you do it?

Why is super gromet style metal head gasket not sufficient? Or is it. <_<

GTRgeoff Grand Master

GTRgeoff

Posted
Posted

An O ringed block will have a groove machined around each bore and a steel ring pressed into the groove. This will apply significantly more pressure to the gasket to prevent it blowing out under higher internal combustion pressures.

It is often accompanied by a matching groove in the head to further trap the gasket. Block O ring (if yoou are getting machining done) costs less than a metal gasket including the OEM gasket.

sewid Grand Master

sewid

Posted
Posted
Wouldn't mind a wiki set up with technical terms like these.. great description GTRGeoff wasn't too sure of it myself..

Good idea :) Wiki's are useful and we can tell everyone to search the wiki instead of the woeful forum search.

R31Nismoid Grand Master

R31Nismoid

Posted
Posted
Good idea :( Wiki's are useful and we can tell everyone to search the wiki instead of the woeful forum search.

What do you mean woeful?

There is nothing wrong with the search functions of this forum.

I use it so often and within 5 mins tops ive found what i was looking for, or enough information to make more questions.

Wouldn't mind a wiki set up with technical terms like these

Well make one yourself, maintain it yourself and submit it to the Admin

(i guess thats where the idea stops eh?)

B33st Community Regular

B33st

Posted
Posted

Here's a link to a wiki that i was playing around with a while ago, dont have a lot of spare time at the moment though. If we can get enough useful info on here i'll register a proper domain name for it. Most of the info can be cut and pasted from other places on the net.

Skyline Wiki

exXU1 Mentor

exXU1

Posted
  • Author
Posted
This is not something for backyard mechanics, but a specialised engine machine shop will have no problems sourcing and fitting.

So is it better than a quality metal grommet style gasket or simply cheaper because one can use a cheaper gasket ?

I assume that one could not use a metal gasket if it hasbeen O ringed?

R31Nismoid Grand Master

R31Nismoid

Posted
Posted
Here's a link to a wiki that i was playing around with a while ago, dont have a lot of spare time at the moment though. If we can get enough useful info on here i'll register a proper domain name for it.  Most of the info can be cut and pasted from other places on the net.

Skyline Wiki

Fatal error: Call to undefined function: getspecial() in /home/content/b/3/3/b33st/html/wiki/index.php on line 97

:lol:

If you wanna talk about setting something up, im more than willing to help with it all, simple enough to do id imagine.

Just gotta have the interest.

GTRgeoff Grand Master

GTRgeoff

Posted
Posted
So is it better than a quality metal grommet style gasket or simply cheaper because one can use a cheaper gasket ?

I assume that one could not use a metal gasket if it hasbeen O ringed?

People use both, as posted above, but it depends on your power requirements.

The gaskets ability to hold pressure is the combination of its own structural strength at its weakest point, the clamping pressure of the head and head bolts, the evenness of the clamping pressure and any ancilliary aids to retention such as O rings or W rings. I've used an RB30 gasket modified to fit the RB25 at a time when RB25 parts were scarce and I had to move the car from Canberra to Melbourne and eventually it just pushed the gasket sideways into the water gallery. Blowing the head gasket could be from displacement, warping of the head, corrosion/poor preparation or a combination of those. The rings help prevent displacement.

Edit: as for is it better than the super grommet gasket, that is using stock gasket and O ring, I don't know. You would have to be producing some massive power for it to have to need better, and so cost would be little inconvenience and you would use the best of everything.

exXU1 Mentor

exXU1

Posted
  • Author
Posted
People use both, as posted above, but it depends on your power requirements.

The gaskets ability to hold pressure is the combination of its own structural strength at its weakest point, the clamping pressure of the head and head bolts, the evenness of the clamping pressure and any ancilliary aids to retention such as O rings or W rings. I've used an RB30 gasket modified to fit the RB25 at a time when RB25 parts were scarce and I had to move the car from Canberra to Melbourne and eventually it just pushed the gasket sideways into the water gallery. Blowing the head gasket could be from displacement, warping of the head, corrosion/poor preparation or a combination of those. The rings help prevent displacement.

Edit: as for is it better than the super grommet gasket, that is using stock gasket and O ring, I don't know. You would have to be producing some massive power for it to have to need better, and so cost would be little inconvenience and you would use the best of everything.

Thanks  for your oppinion Geoff,

i understandall what you said . My main piont and question is that many people use the term O ringedblock as if it is something super special  where i now see it as simply an cheaper alternative( in the long run) than an expensive quality gromet style aftermarket head gasket.

I will run with my Tommie super grommet and new ARP studs for now.

Thank you all for yor input. 

N I B Grand Master

N I B

Posted
Posted

Dave, A quality metal head gasket is upto just about anything you want to thro at it with most big power cars using them but the Oring adds that much more reliability in massive boost cars tuned to the limit like you plan for yours. When using an Oring on a metal head gasket it can take days to settle needing to be retensioned a few times before startup and then retension after its been run.Many 1000+hp cars run the metal gasket alone without trouble but at about $130 to Oring it wont add much to a major buildup and does seem to help if you overheat your engine and leaking after overheating seems to be the only weakness of metal gaskets.

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