Rb25det to Rb26dett

[Newsome]

Just wondering how much work and cost would be involved to put an rb26 into my r33? Are mounts, loom and ecu the same? Thinking of doing the swap so id have more ponies. There could be an rb25det on the market soon

[ontherack]

The loom and ecu are different, and you would need to use an RB26 engine harness and ECU. The sump needs to be modified as well to remove the diff. For the cost of the engine it would be easier and cheaper to tune up the RB25.

[kev.skyline]

first ive ever heard of an engine sump housing a diff, im assuming you mean gearbox needs to be modified to remove the diff. even then would an rb25 box not bolt up to it?
ive never done the conversion and i dont know the ins and outs of it.

[ontherack]

No, the sump actually does hold the front diff



Its not a huge job to get it removed, we had it done to the RB26 in the S14. But the little things add up, to the over all cost of the conversion. The engines aren't cheap, so maybe a top mount turbo, ecu injectors and a map would be cheaper for the performance gains.

The RB25 box does bolt straight up too, so no problem there. The wiring isn't much of an issue if the engine is from either the R32 or R33.

[kev.skyline]

haha, thats mad looking.

[Davie]

id stick with the rb25 cheaper in the long run and not much of a gain,if you spent the money on the 25 ya'd have a serious engine

[Will]

Seeing as how you already have an RB25DET it makes more sense to tune that to get more power, than to fit a more expensive engine set up to house a 4WD system, only to change it to run RWD for the sake of 30bhp.

"Skyline tax" as you should know is bad enough without having "rb26 skyline tax" when paying out for tuning parts.

You`d need the new loom and ecu, different sump.

Yes, the boxes are the same, as already said above.

It WOULD make sense if the car was an NA or an auto and you were doing a conversion anyway.

Although, if by extra power, you meant 600+bhp then the RB26 is a better designed, stronger engine with better internals.

[Newsome]

Thanks for the advice lads. Any of yous know of a nice package for my rb25 anywhere? (turbo, injectors,ecu)

[mick-skyline]

well ive dont the conversion, only because the bottom end went in the 25 on me, so worked out better then to sell off what id done and do teh swap for more power at the same cost. as above diff casing needs cutting out of the sump of the 26 and youll need the engine wiring look and ecu, 25 box bolts straight to it too same clutch and all, not much to it really.