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Head Gasket thickness for Rb26

shoey

By shoey,
in Engines & Forced Induction

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shoey Contributor

shoey

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Hello

I have had my bottom end rebuilt in my GTR and installed Arias pistons that stick out of the block by 8thou. What thickness head gasket would I need to buy to keep the standard GTR comp ratio? I am guessing that 8thou is approx .2mm?

What is a standard GTR head gasket thickness?

Cheers.

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  • 3 weeks later...
shoey Contributor

shoey

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I have a couple of questions then:

1. I had brought a 1.8mm metal head gasket, can anyone guess at what my resulting compression ratio would be? I am guessing that it would be the same as using a 1.6mm gasket on a standard motor?

2. What would be the compression ration if I ran a standard head gasket (1.2mm) with the pistons protruding 8thou?

Just trying to work out the best combination for running R34 N1 turbos on the motor.

Thanks.

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shoey Contributor

shoey

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I will try to rephrase the question:

What is the standard compression ration for a GTR?

How much does this move for a .2mm gasket thickness increase? ie, does it move from 8.5 to 8.9?

Any help appreciated.

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ylwgtr2 Grand Master

ylwgtr2

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you can work out the headgasket volume but you need the diametre of the hole....for the pistons drop them say 10mm down the bore(measure with a dial indicator)then CC it....work out what the volume of 10mm with your bore size then deduct it from the reading and that will give you a minus figure....then do the head then work it all out from there

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