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When do you need a head gasket?

4door_Sleeper

By 4door_Sleeper,
in Engines & Forced Induction

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4door_Sleeper Veteran

4door_Sleeper

Posted
Posted

This a a question for the guys and girls in the know.

My 110,000km rb25det has had a new turbo installed and is making 220rwkw at 14psi. The turbo is/should be capable of more but the tuner left it at 14psi for running in and reliability and recommended that a new head gasket be installed if I increase the pressure much further.

My question is - how good is the std head gasket, and at what boost level should it be changed? I dont really want to know that its good for 30psi for 100km, I want to set it and forget it.

Initially I was going to just let them install the head gasket (my last one cost me $30 for a 6 clyinder valiant) but when I found out that I would be up for $500 plus labour I thought I would seek some advice first.

SK and others please feel free to comment.

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Sydneykid Grand Master

Sydneykid

Posted
Posted

The best example I can give is the 265 rwkw R34GTT which has a standard Nissan head gasket in it. My rule of thumb is, if it needs forged pistons then it needs the block o'ringed.

Personally I never use Jap "brand name" head gaskets, they are rediculously overpriced for a start. How the hell can they justify charging $500+ for an RB26 head gasket and ~$250 for an RB20 head gasket? They are both the same size, in fact the RB20 head gasket has more material in it as the bore sizes are smaller.

If you think you need to reduce the comression ratio, then relieve the combustion chamber volume, using a thick head gasket is technically an inferior solution. It stuffs up Nissan's good work on the squish zones for a start.

:(

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