Just thought I'd fill people in on a bit of info about this.
It's been all the rage locally to use Z32 ECU's to tune R33's. Once the appropriate mods are performed to the ECU this generally works pretty well. But Z32 ECU's are not getting any easier to find, so people have started using R32 ECU's. I've always avoided this as you lose your VCT. But for budget jobs they're quite a good solution.
Well, I've been involved with a few of these lately and they actually work better than I expected. And the lack of VCT isn't that big a deal. We've been simply tying the VCT on all the time. Just snip the wire that goes to the ECU about 6 inches from the solenoid, crimp a lug onto the wire going to the solenoid and bolt it onto the earth near the front of the engine. So intake cam is advanced all the time. We did some tests and in mildly tuned RB25's you lose about 10rwkw right up the top. On most street engines this is hardly noticeable and on drift cars it can actually good cos they're less likely to bang the rev limiter all the time!
In addition, if you use the base image that Matt has provided with the modded code for TPS Trigger voltage, you can set where you'd like "TPS Closed" to come on. R33 doesn't use a switch on the TPS to idicate throttle closed, so the modified code makes it work like later model ECU's - it simply assumes TPS Closed whenever the TPS voltage goes below the trigger voltage. This works a treat, and being able to adjust the trigger voltage allows you to tune out little pesky transition problems from closed to open throttle.
Good things:
- Cheap, easy to find
- They plug directly in (no mods - yay!)
- Easy to tune
- Programmable TPS Idle voltage
If you simply must have VCT working (it IS a good thing after all..) maybe try the "window switch" from Summit Racing:
http://www.summitracing.com/parts/SUM-830452/
* I've not tried these personally but they look like they'd do the job and the price is right.
Pete L