Manifold

[FATAZZ]

i've read on here that rb20 and rb25 exhaust manifolds are interchangable.

assuming thats true.

would a rb25 exhaust manifold flow better then a rb20?

are the 25's bored out more compared to the 20's?

its time for a new manifold but i would like to retain the stock look

but also like to help my turbo breathe.

its a rb25 turbo im using so yeh.

cheers

aaron

[Waldo]

rb25's have circle exhaust ports and rb20's have oval shapped....i think

[FATAZZ]

thanks waldo, ill check that out.

[SteveL]

rb25's have circle exhaust ports and rb20's have oval shapped....i think

No, Rb25 and RB20 have the same port shape and the exhaust manifolds are identical, more or less. It's RB30 that has round exhaust ports.

[T04GTR]

yeah. there the same. there might be some very small diferances internaly.

but they would be negligable..

[FATAZZ]

kool,thanks guys.

[stricko]

So an aftermarket inlet plenum for a RB25DET would fit an RB20DET then? Is that correct?

[predator]

no.. inlet plenum side is different between rb20 and rb25.

exhaust manifold side is the same.

That is the way it is.

[stricko]

Oh ok. I must have read the previous posts wrong. Cheers for the info though.