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just wondering if it would be to put posible and how hard it would be to put an rb26 head on a rb25det

i want to do this because i am thinking of doing an rb30e/rb26 conversion in the future but right now i want to change to a plenum that doesnt run piping accross the top of my engine and i thaught why buy a new plenum for my engine when i will be changing eventually to an angine with a rb26 plenum. im not expecting to get any increase in power

but then i can get my car ready for the rb30e bottom end.

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I dont think you can do it very easily because the 26 uses a completly different sensor / injector system so if your using a power fc you will need to sell it all and run a 26 loom and computer. unless you spend lots of money and time to get it going but you will have to do that with a 26/30 as well...

if your using a aftermarket computer thats wired in then just rewire it and away you go.

Edited by Guilt-Toy

physically it's pretty much a straight bolt on, although you'd want to make sure you got the entire head including the loom, turbo's, dumps etc (perhaps pick up an entire engine where the bottom end has let go?).. rb26 ecu's come cheap on the for sale thread so have a look there.. the only physical difference apart i can think of is the rb26 has larger head studs than the 25 (i think).. not exactly for the light hearted but it's certainly diy achievable, good luck :D

you would be better off just putting a 26 in there. then changing later to the 26/30 conversion

do not want to do this due to the extra cost of bottom end when i will not be using it later on.

also i hear the rb26 head has different volume will this cause problems.

and i thaught i would probably need a different timing belt too.

Timing belts are all the same through the rb range...except 30 hybrids.

You can just use rb25 headstuds..like people do with rb26's on 30's as 25 and 30 share same size headstuds.

However you would lose vct.

Edited by r33_racer
Timing belts are all the same through the rb range...except 30 hybrids.

You can just use rb25 headstuds..like people do with rb26's on 30's as 25 and 30 share same size headstuds.

However you would lose vct.

when you say loose vct i know the rb26 is a non vct head but will i have to do anything to the bottom end like block up oil gallaries or anything or will putting the head in with an rb26 gasket do this automatically

Plugging the VCT oil supply in the block should not be an issue but sealing water in at that front gallery may be a problem . The logical solution is to build the RB30 up with your RB26 head and not get side tracked with short term fixes . This way all your financial and time resources are going into the final product .

I believe people have used RB25 sensors and loom/PFC to run the RB26 heads electrics .

Cheers A .

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