IS-F transmission computer transplant?
#1
Lexus Test Driver
Thread Starter
IS-F transmission computer transplant?
I know this goes against what the LS 460, especially a LWB one, is at the core...a high-end luxury vehicle, built to effortlessly, and in supreme comfort, munch major miles...however, I'd love to 'tighten up' the transmission's shifting a decent amount. I've never been a fan of transmissions which 'slur' their shifts, but even on 'PWR', and a week after changing to synthetic trans oil + a new filter, while it feels a little quicker/firmer, give me what some would consider harsh shifts, and I'll be happy.
I had the transmission computer in a '05 Cadillac STS tweaked to shift as quickly as a C4 Corvette. It'd hold gears and bounce off the limiter if I wanted, and unless at low speed, it'd shift when I told it to, if in 'manual' mode. I really wanted it to, if I put it in 5th at a stop, to actually be in 5th and to stay there until I told it, otherwise. This is just an example, not actually useful.
This Spring, I plan to modify the valve body/converter locking of the Torqueflite 46RE in our '98 Jeep 5.9L to be, if I want, effectively a manual without a clutch pedal. Getting around the converter lock is easy on that beast, just remember to unlock it before coming to a stop! I know a guy who may be able to build a switch for it which works under certain conditions (at least 2nd gear, not in low range, OD switch not 'off').
However, the IS-F's computer does exactly what I want. It's aggressive, even locking the converter in 2nd while in "sport"...AND SHIFTING LOCKED! From. The. Factory.
Yes. This is what I want as my manual selection. 0.1 second shifts and shifting while locked up.
The IS-F put out about the same torque 460 (371 vs. 365), so we're safe, there. But the electronics...I wonder if they play well. The computers, based on fleabay images, have a different connector layout, so it's not 100% plug-n-play...probably. But it's unclear what goes where and if it'll even work. Plus, IS-F transmission computers aren't inexpensive for a what is, for now, a knowledge experiment.
I happen to have a spare, non-sport, suspension computer on the dining room table for reference on plug size/shape. I may post over on the IS-F board, too...they may know, and are more likely to modify stuff like this.
I had the transmission computer in a '05 Cadillac STS tweaked to shift as quickly as a C4 Corvette. It'd hold gears and bounce off the limiter if I wanted, and unless at low speed, it'd shift when I told it to, if in 'manual' mode. I really wanted it to, if I put it in 5th at a stop, to actually be in 5th and to stay there until I told it, otherwise. This is just an example, not actually useful.
This Spring, I plan to modify the valve body/converter locking of the Torqueflite 46RE in our '98 Jeep 5.9L to be, if I want, effectively a manual without a clutch pedal. Getting around the converter lock is easy on that beast, just remember to unlock it before coming to a stop! I know a guy who may be able to build a switch for it which works under certain conditions (at least 2nd gear, not in low range, OD switch not 'off').
However, the IS-F's computer does exactly what I want. It's aggressive, even locking the converter in 2nd while in "sport"...AND SHIFTING LOCKED! From. The. Factory.
Yes. This is what I want as my manual selection. 0.1 second shifts and shifting while locked up.
The IS-F put out about the same torque 460 (371 vs. 365), so we're safe, there. But the electronics...I wonder if they play well. The computers, based on fleabay images, have a different connector layout, so it's not 100% plug-n-play...probably. But it's unclear what goes where and if it'll even work. Plus, IS-F transmission computers aren't inexpensive for a what is, for now, a knowledge experiment.
I happen to have a spare, non-sport, suspension computer on the dining room table for reference on plug size/shape. I may post over on the IS-F board, too...they may know, and are more likely to modify stuff like this.
Last edited by mckellyb; 01-19-18 at 07:03 AM. Reason: grammar atrocities
#3
Lexus Test Driver
Thread Starter
Yeeeeeaaaah, no.
I've had this car 16 months, I plan on having it quite a while longer.
Did the F-Sport come on the LWB model?
Rev-matching downshifts...for the transmission-longevity WIN!!!
I've had this car 16 months, I plan on having it quite a while longer.
Did the F-Sport come on the LWB model?
Rev-matching downshifts...for the transmission-longevity WIN!!!
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