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Is this at all possible?

I assume you're gonna have to get MV Automatics to beef up the box?

Due to the totally different torque curves it could make for interesting calibration of the shift points.

My guess is the auto ecu will change up too early in the rpm range for an RB26.

It will just be getting into stride when it changes up a gear.

Plus it most likely won't change down early enough to lift the rpm higher.

At low to mid rpm it will think there is more torque (from an RB25DET) than there really is (from an RB26DETT).

At this point my brain is starting to hurt, so I will stop.

:P cheers :D

manual shifted auto would work fine i'd imagine (meaning no ecu input at all) but u gotta manual shift fulltime so depends what u want to use it for? y waste a perfectly good engine like a 26 behind an auto box unless u r pulling serious power and 1/4 mile times anyway? :cool: id rather a manual rb25 than an auto 26 :P

Edited by CruiseLiner

There just happens to be an article regarding this in the current Zoom magazine (with the purple 2JZ-GTE-powered Mk1 Escort on the cover).

They're using an autobox (the 5-speed RE501A) in their RB26-powered R33 sedan, and apparently the ECU for the RE40A and the RE501A are one and the same. Further to this, the RB26 computer has ECU pin-outs for controlling an autobox, and all you have do find out is how it is controlled on an auto R32 GTS4 (RB20DET power with auto and ATTESSA), and go from there.

There's more info in the article, so might be worth picking it up, but that's the basics of it. Actually, I read it earlier and remembered someone had posted this question, and thought "how's that for timing?!?!"

Cheers,

Nick T.

There just happens to be an article regarding this in the current Zoom magazine (with the purple 2JZ-GTE-powered Mk1 Escort on the cover).

They're using an autobox (the 5-speed RE501A) in their RB26-powered R33 sedan, and apparently the ECU for the RE40A and the RE501A are one and the same. Further to this, the RB26 computer has ECU pin-outs for controlling an autobox, and all you have do find out is how it is controlled on an auto R32 GTS4 (RB20DET power with auto and ATTESSA), and go from there.

There's more info in the article, so might be worth picking it up, but that's the basics of it. Actually, I read it earlier and remembered someone had posted this question, and thought "how's that for timing?!?!"

Cheers,

Nick T.

I HATE Zoom, they only tell the good stuff, never the bad stuff. They gloss over the real problems and only mention the bleeding obvious. I can get almost any engine ECU to talk to the Auto ECU, that’s easy. The usual problem still exists, the RB26 ECU has no ignition retard/cut mapping for the auto gearchanges.

In regard to this subject, their track record is shyte, Zoom had a story a couple of years ago on an auto R33GTST with a Power FC in it that they reckoned worked fine. I drove that car and I can tell you it was terrible, very harsh gearchanges and manic kick down whiplash. I drove it around the block and warned the owner that the gearbox would die from the lack of ignition retard/cut to soften the impact of the gearchanges. A month later it died, ripped the hell out of the 2nd gear bands and the 3rd gear clutches.

Zoom also reported success with using Wolf ECU’s in auto Skylines, I drove one of those in WA and it was exactly the same. Except its gearbox was already just about dead.

;) cheers :)

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