Stock Wiring Harness And Ecu

[Tony1981]

Hey guys, was wondering who out there with an RB30-25/26 engine is running the factory wiring and ECU?

More interested in the ECU, as you can run the factory wiring, get an adapter plug and run an aftermarket ECU :-),

I have a bare RB25 R33 engine, no wiring loom and my 260z has a RB30 engine, wiring loom and chipped ECU in it currently - even at this point, all my current engine wiring has to go to make way for the RB25 head, but not sure about which way to go!!!

I slapped a turbo on the side of the RB30 engine and then chipped the ECU, however, wasnt overly happy with the way it turned it, A/F ratio's werent quite right, was a bit doey, didnt make as much power as I would have thought (170rwkw on 14psi with t3/t4) and throttle was very weird,

Basically looking to save myself the R&D, of buying an R33 wiring harness, trying to chip an R32 ECU (if it will even plug into the R33 loom) playing around on the Dyno and then just going out and buying an Autronic anyway,

I have read through that RB30DET Faq and it says the stock wiring and ECU can certainly be used, but maybe better only as an interim measure? I cant see any reason why an R33 RB25DET wiring harness and ECU wouldnt work properly with the RB30DET engine, but any first hand experience would be greatly appreciated!!!

[bubba]

If you use the wiring/ecu to suit the head you're using, then that is the easiest way.

I'm using a my factory ecu (remapped) to run my 25/30 but I'm using an RB25DE head out of an R32 so it was mucho easy.

[Tony1981]

My RB25DE didnt come with the wiring loom - so would have to grab one,

Just curious how I would tell which R33 RB25DE wiring loom to get?

There is a series 1 and series 2 R33 RB25DE right?

Then there would obiviously be a harness that suits the N/A and Turbo engines respectively,

My RB25DE engine/head is from a 1993/4 R33 (I think) but is there anyway I can make sure I purchase the correct wiring loom? or does it really matter?

I assume the turbo harness has stuff like a knock sensor, whereas the N/A loom wouldnt,

Also - I would probably want to use RB25DET injectors and RB25DET turbo ECU

[bubba]

Really know fk all about 33 stuff, sorry dude.

Also unless you have someone near you that can remap 33 ecu's, I wouldn't be using one.

The reason I kept mine was because I could get it remapped which was needed by the way. The 30 maxxed out the standard airflow meter pretty quickly and I needed a remap to run the z32 afm, figured while I was there I might aswell chuck some bigger injectors in too (don't know how close the stockers were to maxxing out).

[Tony1981]

Yeah been reading and it looks as if the R33 cant be re-mapped and I wouldnt be able to use the R32 ECU as I am keeping the VCT,

Oh, Autronic's are expensive!!!

But if I used the R33 turbo ECU, injectors, AFM and loom and kept the boost low, like 8psi - the ECU should be able to run that shouldnt it? I would guesstimate that to be around the 180-200rwkw with the RB30DET engine running the stock R33 RB25 turbo - or is the stock R33 turbo ECU incapable of this?

[bubba]

From what I've seen the R33 ecu's tend to hit R&R sooner than the R32's.

e.g. When we built my 30 I had it running on the stock ecu, any more than 10% throttle or 3000rpm and it was into R&R. It was also maxing the airflow meter at about 6000rpm (afm maxes, ecu can't read more air so stops throwing in more fuel). Was running 10psi through RB25 turbo.

I had a remap chip from a groupbuy on here that got me round for a couple of months (had no afm cut) while I collected injectors, afm and saved for the tune.

We kind of under estimated the engine as we didn't expect it to max things quite so quickly..

[Tony1981]

What do you mean by into R&R?

Well I guess no matter which way you look at it the stock ECU isnt probably going to be a long term option stock with the RB30 bottom end, even if you do go with a stock turbo, injectors and AFM,

Guess a more straight foward option would be to use the RB25DET harness, ECU and then plug in an APEXI or something like that!!!

[bubba]

R&R aka Airflow cut.. the stock ecu's have a failsafe where if it sees over a certain voltage from the airflow meter it throws in a bunch of extra fuel and retards the timing.

[R34GTFOUR]

Really know fk all about 33 stuff, sorry dude.

Also unless you have someone near you that can remap 33 ecu's, I wouldn't be using one.

The reason I kept mine was because I could get it remapped which was needed by the way. The 30 maxxed out the standard airflow meter pretty quickly and I needed a remap to run the z32 afm, figured while I was there I might aswell chuck some bigger injectors in too (don't know how close the stockers were to maxxing out).

the harness for the r33 rb25 is the same regardless if its n/a or turbo, series one or series 2, nissan was smart like that.

If you look at a n/a engine bay, certain plugs that are used only for the turbo application are still there but are just taped aside.

I have a complete loom for a rb25, pm if interested.

[daisu]

Could use a Z32 ecu

It is remappable, has VCT function, it may even run the RB30DET with out a remap (provided you used the same size injectors/afm etc)