engine swap advice

[BongRips]

So I have my rb20det and tranny listed at 1000 plus removal and transportation and once that's sold I'll be grabbing an rb25det to throw in. What my question is, which rb25det is the best to build?

[BongRips]

Also, swapping out turbo on the rb25. Should I stick to a bolt on with internal wastegate such as

http://cgi.ebay.ca/Turbocharger-turb...item4cf8456a95
or
http://cgi.ebay.ca/R32-R33-R34-RB25D...item27b2e3eb36
and are they steel wheel? Looks like it to me.

OR, should I switch to a top mount manifold and a turbo with external wastegate such as,

http://cgi.ebay.ca/Turbo-kit-Nissan-...item27b9a7aab7
or
http://cgi.ebay.ca/NISSAN-SKYLINE-R3...item2559f41370
but not necessarily those turbos.

[cschepp]

If I were to do it all over again I would have grabbed a neo engine and trans. R34 engine and much better to mod in my opinion.

[Skym]

NEO RB25DET has the worst CAS (known problem). Can run a crank disc (new damper), sensor, etc setup to solve the CAS problem and need a Link, Motec, Vipec or similar ECU to work with it.

If it was me, R32 RB25DE head (same sensors as RB20DET) and Nissan RB30 bottomend. That's with retuned stock RB20DET ECU.

Or R33 RB25DET (Series 1).

[cschepp]

I just thought if he wanted to do a rb25 he could have the closest shot to a 26 in a neo. Most of the stuff in the bottom end should be same as well as alot in the head. Nice engine for what it is. And yes that is a well known problem but isn't there a way around it? I think a couple guys on sau figured that one out. It's been a while since I've seen the thread explaining things though

[Skym]

There's a company (Ross) that sells a custom CAS setup for RB engine -

http://blog.rossperformanceparts.com...ssan-engine-2/

Also they sell a crank damper with timing disc, sensor for RB engine -

http://blog.rossperformanceparts.com...an-rb-engines/

[BongRips]

So the R33 S1 engine and tranny is better than the S2?

[Skym]

From what I understand, Series 2 R33 RB25DET got new features like shutting off each coilpack via ECU (ignitors shifted from ignition module on top of back of engine to each coilpack). That's instead of removing coilpack cover, etc and unplugging each coil pack like on RB20DET, Series 1 R33 RB25DET. That coilpack shutoff feature was used on NEO RB25DET ECU and same ignition system setup. So was thinking Series 1 R33 RB25DET was the safe option (make sure it doesn't have the same CAS as what's on R34 NEO RB25DET since S2 and NEO RB25DET have the same ignition system setup). But haven't checked a Series 2 R33 RB25DET CAS to see if it has the Mitsubishi logo in the middle of black part of CAS (better than CAS setup on R34 NEO RB25DET).

Problem with R34 NEO RB25DET is if cambelt is loose, it can wear the front of exhaust cam to CAS shaft joint (backwards and forwards movement) and cause the CAS problem (fluctuating ignition timing). At least that's what I was told by a expert. Similar wear problem when bouncing off revlimiter with stock oilpump drive on R32 engine.

[BongRips]

So what is the CAS? (sorry I'm a noob) And what you're saying is the CAS' with the mitsubishi logo in the center of the black part is the better one right? And from what you're saying, the S1 engine has that, correct?

[Skym]

CAS = Cam Angle Sensor. The silver coloured sensor on front of exhaust cam.

R32, R33 have the Mitsubishi CAS (Mitsubishi logo on black part in centre of CAS). R34 has the Hitachi CAS. Just not sure if Series 2 R33 RB25DET had the Mitsubishi CAS or Hitachi CAS. But being hydraulic lifter I suspect Series 2 R33 RB25DET has the Mitsubishi CAS. NEO R34 RB25DET being solid lifter (solid cams) has the Hitachi CAS.