pcmhacking.net

so i'm scoping 2 projects. at the moment i've got an st141 corona which will likely end up with a 3.5 magna v6 and either an a340 (bolt up using pajero bits, but allegedly only as strong as a 4L60E.) or a jatco 4er03a (i think that's what it's called. tt 300z box among others.) if i'm looking to make more power. using a '424 and 11p to run the show.

the other deal is a 2wd tf rodeo with a 4jb1t in it. i can get an a340 to bolt up to it from an early d-max. i drag race it occasionally. just for lols at the moment. pb is 17.25. about to get an intercooler and a bigger pump element. auto is better for drags, and the taller top gear will help with highway miles.

my questions are these, 1. when using a 424 to control an auto, i came to the conclusion i could compare application charts between boxes and connect the shift solenoids the same way. is this the case? lockup and pressure control solenoids will just hook up won't they? 2. with using a controller on the rodeo, if i can connect a tps, coolant temp, map sensor and some way to give the computer an engine position signal then hook up a speed sensor and the auto solenoids, will it care if it isn't driving a coil or injectors? can i fool the idle speed control part with some resistors?

3. for the engine speed reference, since an ignition module won't be needed and the rpm is limited to ~4000 rpm, can i just use a hall effect cam position sensor and 2 teeth on the balancer? this should give a 2 pulse/rev and let it think it's a camira. will this work?

So I've had a read of vl400's thread, and how to connect up the a340 to a 424 is outlined there. Any suggestions on the other stuff?

briney wrote:1. when using a 424 to control an auto, i came to the conclusion i could compare application charts between boxes and connect the shift solenoids the same way. is this the case? lockup and pressure control solenoids will just hook up won't they?

You most likely worked all this out from my build thread, but for others reading this thread, the shift solenoids are opposite polarity - that is on the A340E the PCM switches 12V, the Delco switches gnd. Lockup is the correct polarity, but the A340E solenoid is a lower resistance and hence higher current, the PCM will likely complain at this. The pressure control solenoid varies in operations, some A340E use a throttle connected cable for line pressure and an accumulator back pressure solenoid (mine is like this) while others have a line pressure solenoid. The accumulator back pressure solenoid can be driven directly from the PCM, but needs some cal changes to make it operate differently. Need to also set the solenoid mapping for switching the correct combination of solenoids for each gear. Another thing is you need to tell the PCM what position the shifter is in.

I do have more of the A340E to Delco PCM interface boards that were in my thread if you want one.

briney wrote:2. with using a controller on the rodeo, if i can connect a tps, coolant temp, map sensor and some way to give the computer an engine position signal then hook up a speed sensor and the auto solenoids, will it care if it isn't driving a coil or injectors? can i fool the idle speed control part with some resistors?

Dont need to fool the idle speed and it wont care about no injectors and coil.

briney wrote:3. for the engine speed reference, since an ignition module won't be needed and the rpm is limited to ~4000 rpm, can i just use a hall effect cam position sensor and 2 teeth on the balancer? this should give a 2 pulse/rev and let it think it's a camira. will this work?

It will work feeding the PCMs ref input, just need to mask the ignition module fault codes though. 11P does not support a 4 cyl, but if you add 4 teeth and set it to 8 cyl should get the correct RPM reading. Since its not controlling fuel and spark I dont think it will be a problem?

rather then create a new thread i'll side jack this one.

what's the minimum or recommended thing to do if i want a stock vx ecu to control the trans only? I'll be replacing the engine running side with a haltech elite for a turbo'd v6 and i can't be bothered wasting time with flashing/scanning the stock ecu.

this is a burnout car so gearbox blowing is expected anyway then it'll get a manual valvebody, but for now i want to set it up as best as possible

i'd use a 424 pcm in the VX and use $11P for boost.

so not possible for the original ecu to sit there just controlling the trans? Essentially just having the haltech control spark/fuel by taking injector control and the EST to the factory DIS module.

As a minimum would need to have TPS and engine RPM from what I can think of, along with all the normal transmission stuff like vehicle speed, transmission temp, PRNDL info, etc.
Not sure how many people have actually done this so you're pioneering a little bit.

i consulted a mate. he has told me what needs to be done.

my guess was right. we basically share the crank/tps signal with stock ecu. wire in injectors, EST & bypass wire to haltech. stock ecu wont know or care. it's not controlling shit.

Thanks guys. Could I use $11p on a 6cyl setup? Some logging of engine parameters will be nice too.

Tre-cool if it's just a skid pig, why spend a shitload of money on a haltech? Why not just set the existing ecu up with real time tuning and use it? Or use a '424? Keep the money for tyres.

11P can be used on 6 cylinder yes. Great logging capacity via USB can even log with your Android phone if you want.