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Hi. I am contemplating buying an R33 RB25DET PowerFC for use on a R33. For the time being, the PowerFC will be tuned to run an RB25DET with stock turbo. However in the near future, I plan to put in an RB30DET running an R32 RB25DE head without VVT. Will the R33 PowerFC still run this fine (not having VVT)? I will use all R33 RB25DET sensors.

Also, what kind of injectors does the RB25DE (R32) head use? Are they top feed or side feed?

Thanks in advance!

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you will need to use the R33 RB25DET loom, and all the sensors should then plug in. the lack of VVT will not be a problem at all. mine isn't plugged in at all. your tune might need some patching up though, due to the camshaft timing not changing any more.

Seriously consider keeping the VCT unless you are going to go massive cams. If you are looking at massive cams go the rb26 head.

The R32 RB25 head really is only a good option for the R32 as it allows a stock look without modification of wiring/sensors or injector types.

The R32 heads are fairly rare these days, I've only seen R33 Rb25de heads at the wreckers lately.

Besides the point the R33 rb25 head is slightly better (has slightly larger ports and better designed plenum) than the R32 rb25. Only slight.

In the real world it appears to make no difference to power outputs.

The VCT however does. Definitely worth keeping the VCT.

The R32 RB25 head does bolt up without mods.

BUT... The VCT isn't a LOT more work, its very minimal.

Don't worry about it just dive in and do it. There's plenty of information around on how to do it. Measure the rb25det vct oil restrictor and be sure to place one in the feed to the vct from the pressure sender.

The point is... You will find plugs and connections to be different with the r32 rb25de head, not to mention different injectors, throttle body etc..

Its more work doing that than having your engine builder block off the vct oil supply drill and tap a new one.

Yeh, I have pretty much gone through all of the pages in that thread. Along with reading the PDF guide. Very informative, and great work. However, if I use the RB25DE head from the R33, won't that also mean the head will need to be welded to seal the water galley on the RB30 block, along with blocking off VCT oil supply, tapping new one, etc.. As opposed to just putting the current R33 RB25DET sensors in the R32 head. Just seems easier.

Hmm. Now I don't know which path to take. I guess I'll see what head is available for what price. How much would it cost (approximately), to modify the R33 head, with regards to VCT oil supply? Thanks for the feedback guys!

Well I did get the whole engine built there, but really - to hook it up, you just need to drill and tap a fitting at the front of the head into the oil gallery, get a piece of braided hose and some fittings.

Just put a t-piece onto the oil pressure sender for it to hook into. :(

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