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Gday all, just a quick question....

Ive been readin that the rb20det head is restrictive when compared to the rb25 head. What would be better in your opinion, fitting the rb25 head, or having the rb20 head worked on to improve flows etc..

Would swapping the head for a rb25 also involve swapping the manifolds etc., so would the eventual costs outway doing this?

Also, anyone had work done to their rb20 head, and what were the results? I'm thinkin of fitting the metal head gasket at the same time (I've heard but might be wrong, that it helps prevent a blown motor).

Cheers for your opinion,

Bl4cK32:)

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You will probably lose a HEAP of compression by fitting the 25 head - it likely has bigger combustion chambers.

The RB20 head does clean up nicely, but I've managed to hit the rev-limiter (8k rpm) with the standard RB20DET head. So I don't think it has much of a problem breathing.

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Bl4cK32, a RB25 head won't line up on a RB20 block. Different size bores, etc.

Read sydneykid's posts re: metal head gasket. They cause problems and don't solve any issues that can't be fixed with head work.

http://www.skylinesaustralia.com/forums/sh...25&pagenumber=1

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  • 6 months later...

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