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Head work

Bl4cK32

By Bl4cK32,
in General Automotive Discussion

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Bl4cK32 Grand Master

Bl4cK32

Posted
Posted

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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blind_elk Grand Master

blind_elk

Posted
Posted

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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Gradenko Mentor

Gradenko

Posted
Posted

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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