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Unless you come across a blown RB25 then it is hard to find a RB25 head for a decent price.

The cheapest I came across was a Rb25DE head that set me back $750.

At the time that was a damn good price as others were asking 1k+ and thats if they had one.

Its a matter of luck if you come across one cheap and have the money at the time.

Darren,

The design is different.

There is no way you can but up an R33 inlet manifold to the R32 head.

If the motor is to go into something other than a skyline e.g. VL. Is it possible then, to buy say an R32 RB25DE complete engine and loom/ECU package, and combine the necessary parts etc entire top half of the motor including loom and ECU injectors, the RB30 bottom end, and an RB20DET exhaust manifold with chosen turbo ?? I have been noticing complete engine packages for around $1500. this seems the cheapest way to me, to get things running until bigger injectors and fueling requirents are needed? or am i WAY off?

hell_bound: yes, thats the idea :D I am not sure that the rb20det ex.manifold will fit though. That was my other option.. complete RB25DE which i did find a few prices and would have been around $1200 complete. Heads can be carried though, whole engines are a bitch to cart around.

sciby: your plan sounds a little similar to mine. I am going to *attempt* bolting everything together and putting it into an R32. Once its in, just get it working in basic form, iron on the kinks, etc and run a standard rb25det turbo or similar with very low boost. After that take it to a workshop and budget $6k or so and get them to build the bottom end and maybe do some work on the head, choose a big turbo, etc. At some point the gearbox also has to be converted to an RB25DET from auto.. yes its going to be a long process but hey, that is the fun :O

Yes, that also makes no sense to in/out twice, but it does take much of the labour costs out of it getting in there first time myself. Its going to be the fiddly stuff that costs workshop hours to sort out, I'd rather attempt that myself, and call in the experts where necessary or something is too difficult.

I'm almost tempted to see how the VG30 BB Turbo makes power.

Even though the compressor is slightly smaller than the rb25t turbo I wonder if the larger exhaust a/r will help prevent power nudging over at 5500rpm.

After all it does make 190kw at the flywheel on std boost on a VG30DET. :D

yes, better get the latest version.. i am reading off one dated 28th march :P

I take it that means the stock R32 RB25DE loom and ecu is able to support a turbo application e.g. correct knock sensors ?

i believe the basic loom is the same, and the plug sockets even the same.. but you will need to run a turbo ECU of some type at least, as I can't see why a n/a stocker would support turbo properly. Don't think it has the knock sensor which is a good idea for safety - so you would want to wire one in.

If I am wrong somebody correct me.

Picked up my turbo on friday :P a GT30R. Where's the best (read:cheapest) place to get blank inlet flanges. I need a couple to make an adapter for the external gate.

Also, when i put the GT30 gasket against my RB20 manifold, it appears the manifold opening is slightly larger so the gasket will not mate properly. Is the opening in the twin inlet turbo larger than the single opening? Even though they are both T3 flange.

sorry to re-hash over things guys, seeing as my combo is going into a VL , i was wondering if the R32 RB25DE loom and ecu is able to run my RB30DET combo? What i am getting at is that if buy a complete RB25DE engine and loom/ecu , then i can use the entire top end except the exhaust side, where i will fit my turbo manifold etc. any help would be extremely good !!!! or should i just buy a RB20DET engine and loom/ecu package and try to source the head buy itself??

Holes line up, height is identical, but the width is out by about 3mm both sides. I've never seen an RB20 turbo, but my guess is it is a twin inlet.

Not going for mega power due to standard RB30E internals. 400-450BHP at 15 PSI should be gettable.

Turbo is straight out of the Ballistic Concepts catalogue. Part No. SB8006A. 0.82 A/R Exh, GT40 Comp, 0.70 A/R, 64 trim.

I'm thinking of Spot welding....

 

Yeah thats actually how I am doing it.

I am using the RB30 Bottom and the Rb26 Top.. and there is only a very small gap.

I have bent the metal into shape.. and then just spot weld it on at the back. Easy.

Paint it, and it will look mint.

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