O-Ringed head
04-08-2002, 06:07 PM
#2
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This mean that a wire is put in position (a "ring" to put the wire in may be machined into the head) between the head and headgasket to lay pressure on the headgaskets fire-ring.
The advantage is that the headgasket most likely will never blow, now matter what.
The disadvantage is the same as above, because you are better off blowing a headgasket than breaking som other engine components(ie rods, and pistons).
This is often used in engines where blowing the headgasket is a common problem. Normally, the headgasket will not blow until there is something wrong with the engine. Thats when you'd rather let the headgasket blow than your internal parts. But some engines need this badly when increasing intake pressure.
Correct me if i am wrong, but I think the 951 has a problem with the headgasket blowing under high boost situations. Therefor a o-ringed head would be a good idea. Althoug a wide fire-ring headgasket may solv that problem??
Eirik Kvello-Aune
<a href="http://www.diateam.no/porsche" target="_blank">www.diateam.no/porsche</a>
The advantage is that the headgasket most likely will never blow, now matter what.
The disadvantage is the same as above, because you are better off blowing a headgasket than breaking som other engine components(ie rods, and pistons).
This is often used in engines where blowing the headgasket is a common problem. Normally, the headgasket will not blow until there is something wrong with the engine. Thats when you'd rather let the headgasket blow than your internal parts. But some engines need this badly when increasing intake pressure.
Correct me if i am wrong, but I think the 951 has a problem with the headgasket blowing under high boost situations. Therefor a o-ringed head would be a good idea. Althoug a wide fire-ring headgasket may solv that problem??
Eirik Kvello-Aune
<a href="http://www.diateam.no/porsche" target="_blank">www.diateam.no/porsche</a>
04-08-2002, 09:53 PM
#3
Nordschleife Master
[quote]Originally posted by mmmbeer:
<strong>Therefor a o-ringed head would be a good idea. Althoug a wide fire-ring headgasket may solv that problem??
[/URL]</strong><hr></blockquote>
I agree. I dont know of many people that push more than 20lbs. Im sure a wide fire would to the job at those pressures
<strong>Therefor a o-ringed head would be a good idea. Althoug a wide fire-ring headgasket may solv that problem??
[/URL]</strong><hr></blockquote>
I agree. I dont know of many people that push more than 20lbs. Im sure a wide fire would to the job at those pressures
04-08-2002, 10:57 PM
#4
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The boost is not 'directly' the cause of the head gasket failures. Usually the cause is detonation. You can detonate at very low boost levels too. It is however more common to detonate at high boost levels. O-rings help to give a buffer zone before the gasket gives up. You can still blow a headgasket even with o-rings. <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />
04-09-2002, 02:08 PM
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Derrick is right. I had my 86' 951 head O-ringed AND I was running a wide fire ring gasket and still managed to blow the head gasket. I don't think it was a case of too much boost as I was running just under 1.2 bar when it happened. I was using a 50/50 mixture of 110 octane race gas and Sunoco 94. My Huntley Racing ARM1 gauge indicated dead rich under full boost and I was running bigger injectors the fuel pressure cranked up a bit.
Go figure?!? I'm thinking that my advance curve must be too agressive or I've had some sort of head stud failure. Haven't torn it apart yet.
Go figure?!? I'm thinking that my advance curve must be too agressive or I've had some sort of head stud failure. Haven't torn it apart yet.
