MegaShift for 1JZ GTE 4FAT tranny

A forum for discussing applications and implementations of the MegaShift transmission controller code for the GPIO from B&G. This can control up to 8-speeds and 6 shift solenoids (plus a 16x9 table for controlling a PWM line pressure valve). It has manual and fully automatic modes (16x9 load x speed table), with under and over rev-limit protection, and full data logging of all inputs and outputs (among many other abilities). A TransStim to test your completed board is also available.
Post Reply
mxsteven
Posts: 2
Joined: Thu Jul 03, 2014 11:08 am

MegaShift for 1JZ GTE 4FAT tranny

Post by mxsteven »

Hi,

I wonder had anyone done MegaShift for 1JZ GTE 4FAT transmission? I am interested to work it out since I had transplant the 1JZ to my BMW E46 and would like to hook up the CANBUS to instrument cluster too.

Someone had sent me the tranny manual and I can see there is 7 solenoids. Any guideline for this would be greatly appreciated!
Screen Shot 2015-09-18 at 8.18.58 PM.png
Screen Shot 2015-09-18 at 8.18.58 PM.png (308.17 KiB) Viewed 11906 times
Bernard Fife
Posts: 1696
Joined: Fri Apr 04, 2008 1:28 pm

Re: MegaShift for 1JZ GTE 4FAT tranny

Post by Bernard Fife »

mxsteven,

At first glance, MSHift could work for this transmission. MShift can control up to nine outputs for shift solenoids (the default is four, but up to five other outputs can be repurposed). You'll need more information about your trans to implement MShift, the additional information required is covered here: http://www.msgpio.com/manuals/mshift/newtrans.html

You may have more trouble hooking MShift up to the CANbus in your dash. That will require having a lot of information about the sorts of signals sent to the dash in its OEM configuration (message format, memory locations, variable formats, etc. etc.).

Lance.
"Never wrestle with pigs. You both get dirty and the pig likes it." - George Bernard Shaw
mxsteven
Posts: 2
Joined: Thu Jul 03, 2014 11:08 am

Re: MegaShift for 1JZ GTE 4FAT tranny

Post by mxsteven »

Thank you Lance for the explanation.

I think it is worth while trying and btw i had all the canbus info which i planned to use ms3 paired with this mshift.. Tranny tuning pattern i think it is basic ladder map.... Wonder can it send a signal for retard the ignition for every gear change? Aka flat shift style? I think this would protect the tranny better.

What do you think?

Thanks
Steven
Bernard Fife
Posts: 1696
Joined: Fri Apr 04, 2008 1:28 pm

Re: MegaShift for 1JZ GTE 4FAT tranny

Post by Bernard Fife »

Steven,

MShift sends separate upshift and downshift retard amounts (i.e. retard during a shift), as well as in-gear retards (retard when in a particular gear). These are sent to the engine controller over the CANbus.

You can read about this here: http://www.msgpio.com/manuals/mshift/V5tune.html#ga

Lance.
"Never wrestle with pigs. You both get dirty and the pig likes it." - George Bernard Shaw
phoenix3d
Posts: 11
Joined: Wed Jul 16, 2008 2:55 pm

Re: MegaShift for 1JZ GTE 4FAT tranny

Post by phoenix3d »

Hi Lance..

If I am not mistaken this is the A650E trans. :?:
I also have one of these that need to be DONE urgently.. :? mated to a 1UZ-FE VVT-i plant (Now working correctly thanks to James & MS3-Pro module)

I have a bit of info I have been able to scrounge together..

A Bit of a strange one this trans... a bit if a trick for second gear shift...

PWM Frequency of the SLT, SLN & SLU solenoids are ~310Hz
shift solenoids are high side (4 of them)
PWM Solenoids are low side (3 of them)

Input Shaft Speed Sensor = 24 Teeth (VR Type sensor)
Output Speed Sensor = 12 teeth (VR Type Sensor)
Trans Fluid temp Sensor = 25’C (77’F) @ 3.5Kohm / 110’C (230’F) @ 231-263 Ohm

Have a look at the attachements.
Gordon
Attachments
shift Solenoid VIDEO.zip
FLV video showing scoped solenoids in action
(4.68 MiB) Downloaded 507 times
A650E Info for James (Slides).zip
scope traces of Solenoid activity
(556.76 KiB) Downloaded 534 times
A650E Info for Transmission addition.pdf
Info on A650E trans
(644.35 KiB) Downloaded 591 times
phoenix3d
Posts: 11
Joined: Wed Jul 16, 2008 2:55 pm

Re: MegaShift for 1JZ GTE 4FAT tranny

Post by phoenix3d »

Additional A650E Manuals..

Guys Please let me know if there will be problems posting these here.. I will remove them if I have to.

Gordon
Attachments
A650E Info for James (PDFs).zip
Info for A650E
(1.56 MiB) Downloaded 547 times
Bernard Fife
Posts: 1696
Joined: Fri Apr 04, 2008 1:28 pm

Re: MegaShift for 1JZ GTE 4FAT tranny

Post by Bernard Fife »

Gordon,

If this was mine, I would start by assigning (on paper) outputs and inputs in the GPIO/MShift to the various devices on the trans itself. Then you will know if there are sufficient I/O channels and if there are conflicts that can't be resolved (and/or if there are some that could be solved with appropriate code modifications). There is a list of MShift I/O here: http://www.msgpio.com/manuals/mshift/portspins.html

Low side drivers are straightforward, all the GPIO outputs are switched grounds. Apparently some user have converted the driver circuits to be high-side drivers - search the posts in this forum to see how they did this (I haven't done it myself). It may also be possible that the hide-sided devices can be converted to be low-side through wiring changes in the trans (though this may not be possible).

What is the "trick" for the second gear shift? If it is possible to do it, I can try to modify the code to work as required.

310 Hertz PWM frequency isn't a problem, and the rest of the parameters you list also look do-able with the current code as-is.

Lance.
"Never wrestle with pigs. You both get dirty and the pig likes it." - George Bernard Shaw
phoenix3d
Posts: 11
Joined: Wed Jul 16, 2008 2:55 pm

Re: MegaShift for 1JZ GTE 4FAT tranny

Post by phoenix3d »

Hi Lance...

Awesome thanks for the Speedy reply!!

The trick I mentioned is written in the DOC file as well as on the Video of the scoped outputs.

It's something about one or two of the solenoids other than Solenoid 1 & 2 (I think its Sol 3 & Lock up, I May be incorrect at the mo, working from my forgetry) switching on, that switches on for a period and then switches off so as to allow back-flow? of fluid in the trans to initiate change to second....

Toyota has so many Trans it's insane!!....

Ill do as you suggest and try map the outputs, I'll post what I can get together.

EDIT>

So the line pressure regulator actually relieves pressure with increasing duty cycle. At idle or closed throttle the duty cycle is about 50%,
and from about 50% to WOT the duty cycle is about 20%.
All four shift solenoids are just on/off. The other 3 are pwm. If you leave the other 3 disconnected the trans will still operate.

** It takes more than just selecting the shift solenoids to select second gear. You have to do some trickery with the PWM solenoids also.
According to a Toyota new car features article for the GS300 it says that the Lock up solenoid regulator is used like a accumulator to
achieve the change into second gear.

** You first need to switch sol 3 on for one second then you play with the duty cycle of the lockup sol. Then you will get 2nd. The trick is
to trend the Duty cycle according to load the get it to shift decent.

** What sol 3 does is bleed off the pressure that goes to the lockup. Then the lockup will not engage. Then the feedback pressure
controlling the lockup will activate the 2nd control sol. According to your signals you need to pulse the lockup the same time as you open
sol3 for one second. the duty cycle will determine the engage pressure. then you need to increase the pressure afterward for a proper
shift according to the load. It is a difficult one i know

***Update. It seems it needs a momentary application of the lock up solenoid when going into third also, otherwise it is a very s low gear
change into third. The lock up is really solid as even at 30% duty cycle it will cause the car to stall when standing stil l in third.


Gordon
Post Reply