MadMaxSC400

I (and the race shop I deal with) have concluded that the wiring and pin placement on the ECU is vastly different from what the shop manual or wiring diagram say. I have a 1993 SC400, it's a California car. Has anyone seen this? Tried to mess with the ECU and found totally wrong wiring?

Interestingly, the Apex'i SAFC I had on my car for a short time had the right diagram, but it didn't agree with the official Lexus shop manual.

Where can I find the right diagram?

'S'Low Rider

Hi MadMax,

I hit almost the same problem as well on my V8.

After talking to most of the better known 'tuners' over here it was obvious that none of them had ever modified the ECU on a V8 Soarer. So I didn't want to be the first....

The other options I'm looking at is to send my ECU to Japan to MiNes who will add a piggy back chip to the standard ECU. This will remove the limiter, increase the revs, so that I can hold each gear longer and modify the fuelling. I'd expect another 20hp but much quicker starts. Its expensive though........$1500...but at least these guys have been doing the 'mod' for the last ten years!

Blitz also do a piggy back chip for the UZZ30 which does pretty much the same.

Sorry I couldn't be of any more help....

MadMaxSC400

That's what this is, it's a piggyback ECU. But, it's preprogrammable (or will be once we get it tuned up on the dyno) and costs $1000, including a cold air large pipe intake. Sounds like the folks in Japan might know something. I wonder if for example the Australian manual is any different. I'm having the dealer check into it.

stevenj

There is no such a thing as Australian Manual for SC400, believe me. The reason is this Lexus model was never marketed over here, hence no manuals and/or support from Lexus. Of course, there are the Japanese wiring diagrams for the Japanese Soarer. I imported a Soarer from Japan as it has the steering wheel on the correct (right) Australian side. Check: www.startrade.org