One of the lesser know workshop manuals (not Gregories) actually tells you what voltages are required for each shift pattern. That's all the hard work done.

I'll see if I can find my copy, and I'll post back.

i have all the factory manuals

and a dedicated BTR tranny rebuild manual also

but dig ur stuff out

seems a few of u guys are keen on the idea here

nice

cheers

Sorry if I sound rude, but thats all the piss easy work done.

The main shift solenoids and lockup TC solenoids need 12V and the S5 solenoid needs between 200mA and 1.2A of current - variable to change the shift feel.

ok your not being rude

the torque convertor solenoid need a dc current of a 12 volt supply thats easy where the s5 has to be pulsed at a variable frequency depending on the condition required from the trans

so where do we start ?????

seen some methods where guys have push buttons for gear selections for all the solenoids on other transmissions where the BTR is a little more tricker where the line pressure needs to be adjustable at the S5 solenoid

wonder what the line pressure is if the solenoid is fully on ie 12volts supplied to it when the engine is running at light throttle cruise right upto wide open throttle ( LEAD FOOT MODE )

ok will set up a test rig at work with a transmission and start testing some of the stuff have a motor and trany ready to go

cant do it to my every day car be funny driving around wif all these gauges and wiring and buttons in the front seat area LOL


cheers

Hey FPV_GTp, where can I get one of those dedicated BTR tranny rebuild manuals, is it a genuine Ford manual ?

The S5 solenoid needs to idle at 200mA while in normal driving mode which gives a high line pressure. During shifts, the ECU ramps this current up, (anywhere up to 1.2A which would be fully on at 12V) which lowers the line pressure and therefore softens the shift.

If you drive around with the solenoid on, you might not go anywhere, either that or it will slip so much during shifts you'll fry your clutches.

If you use less current during a shift the shift will be firmer because the pressure will be closer to line. (And if you unplug the S5 you'll get damn hard shifts)

Also, the S5 needs to be pulsed at a fixed frequency but variable pulse width.

Its not entirely correct to refer to it as line pressure, its really shift pressure which is independant of line pressure.

hi

the BTR manual is available from APROVED TRANSMISSIONS in melbourne

the ford workshop manaul is available from TECHNICAL BOOKSHOP Melbourne

cheers

The transmission control is really complex. -This is from a textbook on auto trans design.

To give an idea lets consider a 2-3 shift.

One element is coming off (the front band) and another is coming on (the clutch). First the solenoids switch to direct fluid to the correct valves in the valvebody. The S5 is still at maximum line pressure to start filling the clutch piston. But it has to ramp the pressure off to allow the band to disengage then it has to ramp the pressure on again to engage the clutch. The trick is balanceing the release of the band against the apply of the clutch so that the transmission doesn't bind up or flare. This is very difficult and requires different setpoints depending on input shaft torque and RPM. Not only that but transmission fluid temperature has an effect aswell.
Even that input shaft torque depends on where the torque converter is operating and can be up to twice the engine torque.
Finally this shift requires the engine to limit it's torque at exactly the right moment to help with the balance of forces between the offgoing element and oncoming element.

So don't underestimate the difficulty of this project.

We are going to need a PWM duty cycle to run the S5 solenoid, this duty cycle has to be set by tables that allow the S5 to ramp to target points during the shift. Those points will have to be determined from lookup tables that depending on what RPM, Input shaft torque, transmission temp, and degree of shift firmness is required. You will need one profile for every shift that is possible. ie. not just 1-2 2-3 3-4 but 1-4 3-1 etc.

Realistically we will never get as smooth shifting as stock, but I think it should be possible to define a set of shifts that work fairly well for one engine/transmission combo, then just make the engine torque adjustable so when someone mods their engine they just put in their new torque curve and the trans re-calibrates itself.

...it does sound complicated starting from scratch. But since there is so much information on the stock shifting and operation.. then we are just reverse engineering.. and then modifying, no?



Cheers

hi

spork " Realistically we will never get as smooth shifting as stock, but I think it should be possible to define a set of shifts that work fairly well for one engine/transmission combo, then just make the engine torque adjustable so when someone mods their engine they just put in their new torque curve and the trans re-calibrates itself. "

Im sure with all the inputs from the varies sensors a microprocessor of some sort will be able to make the correct and smooth sifting points on the transmission once it is programmed a set of tasks

give a example just one of many if cruising down the road from standing still right up to a speed of say 60 kmh , to get the mass of the car moving one will have to press the accelerator a little more the transmission should be in first gear at a pre programmed point when all the conditions are met it shifts into second gear and so forth until its reaches drive the power that's required to achieve this is anything between 10kwatts up to 20kwatts the S5 solenoid can be controlled to make the shift points nice and smooth between gear changes

but image for high performance application where the throttle is planted down to the floor then we are talking about different power levels the engine will be producing and generally one uses the transmission in manual mode ie do the selection of the gear changes yourself
but there will be guys that are lazy and let the transmission do the changing for them this would be the great benefit for the trans controller and a big test

more fluid pressure is required to apply clutch packs and band to hold the power through the transmission

these are just a few examples but im sure the system would work if a lot of thought and planning was put into the idea


cheers

As Spork said !



Its all very well talking about when the transmission needs to shift but just accomplishing ONE clean shift will be a massive project in itself.

As Spork has outlined, there is a huge sequence of events that need to take place - perfectly - to make to box change gears, not to mention the number of variables involved in just driving the vehicle like engine torque, RPM, road speed, ambient temperature, fluid temperature, engine load, limp home modes, lockup control (not that hard), idling engine up when fluid is too hot, running in lock up mode when fluid is too hot, etc etc.

Everyone complains about how the standard boxs do stupid things, and shift all wrong etc, and Ford would have thrown thousands of dollars and a team of twenty or more people (full time) at the project of designing their ECU.

When a friend and I started designing an engine management system about three years ago, everyone said "controlling an engine is simple".
Yeah right ! There are many people that could get an engine running using a scratch built ECU, but to make it run perfectly is a huge undertaking. We have only now got to the point where we can say we are happy with it, after thousands of hours of programming, and thousands of lines of code.

I now have a much greater respect for those that design factory systems, and they only have one type of engine/vehicle to design for.

Call me pessimistic, but I don't expect BTR control to be any less of a nightmare.

If you're not scared now Skywalker - you will be

we can all talk , but only one way to find out
start something

but where does one start ??

a engine management system i would have to say is totally different to a trany controller

Just bought a EB falcon MPFI 4 speed auto for $100 dollars have a tested bed to start seeing what happens

will get some high pressure gauges fit them to the tranny , temp gauges
a few on/off switches , will get a vairable risistor pack and so on lets see how this sucker really works start playing on the dyno

on the early EA falcon 4speed auto i have to probe with a multimeter and see whats happening on the EB onwards i have electrajet which hooks up direct to the factory ECU and i can see waveforms and voltages frequencys of all the internals of the transmission solenoids no need for a multimeter here

will back probe and see what the S5 solenoid pulse frequency is at varying driving conditions lets see what the ford controller does here

what microprocessor to use MMMMMMMMMMMMMM ????? will speak to a few people and see what they come up with

keep u posted
cheers

Hi guys, I've been considering trying to put together a controller for my 4spd box for a while, and have a spare MRM (http://www.robominds.com/)
which uses an MC68332, so count me in. I'm an electronic engineer, currently undertaking a PhD - so while I don't have much time I'm sure I could lend a hand. Basically I code in C/C++ all day long atm so helping to code is no problem either. Hopefully we can get a reasonable working group together and make this happen, as some tuning for the box is something that everyone with even basic mods would like. As far as needing to design for EVERY shift ie 4-1 1-4 etc etc, if you go about designing the system as a sequential controller with manual paddle/button shift, you can remove all but the direct shifts, ie 1-2 2-3 etc, at the expense of flexibility, which would be a good starting point. Later that could be expanded to full automatic control. I know it sounds crazy to electrically manualise the box, but its probably the best starting point. If you really need full automatic, the system could be designed to pass thru to the original auto controller by either a separate button, or using the econ switch until it con control everything itself.


Justin

A good idea, to manualise it... but that would only get rid of the parameters of when to shift, not how... I think the problem with shifting is how? But ofcourse taking this in steps is alot easier than designing everything at once. The MC68323 seems like a very promising chip indeed! But at $60+ each, or 36 for AUS$ 2,205.31 is a bit pricey. (From RS components).. perhaps you get them cheaper somewhere, but Im assuming they don't get THAT much cheaper? Perhaps something a little less-featured will be more applicable to a DIY budget controller?


Cheers

Definately something cheaper would be the go, I just suggested it because thats what I happen to have lying around, and really the 68332 is targeted to be used for a full PCM or robotics control not just a trans controller so yes its massively over featured.

All you really need is a few A/D converter channels (to read sensors) some on/off style outputs, and a couple of PWM channels. So probably even a staver or basic stamp would do the job (but I wouldn't want to try with something so underpowered). Hell with dedicated electronics to do PWM and A/D you could use something VERY VERY cheap, but would you really want to, it adds to the design complexity and makes programming harder.

If the 68332 (perhaps a slightly cheaper chip ie 68HC912D60A) could do the job and only requires about $50-100 in extra electronics then you have a system thats only $110-170 (68332) or $65-115 (68HC912D60A). Tho the prices are probably unrealistic, the electronics involved aren't that expensive, as has been said further up its more the design of the algorithms that will be time consuming and troublesome. Basically what I'm saying is why go for REALLY cheap and have a pain even trying to get something working, when you can buy a fully featured chip and know that testing and design will be much easier. Even if it costs $3-400 to the end user its a damn sight cheaper than an engine management system, and quite frankly a 68332 with another say $2-300 of electronics basically gets you the equivalent of a motec/autronic if you can program everything right.


Having said all of that I'm happy to work with what ever everyone chooses. I've heard that there is an extention in the works for the MS2 to allow trans control, so perhaps someone can shed some light on what their doing, no use reinventing the wheel if you don't have to.

Justin

Yes, Ive heard about the MegaShift, but its still in development I think, and they are waiting for the router board... which should be available soon.

Underpowered is not good... I guess its just hard to grasp paying over $100 for something that doesn't even exist yet.

Can't seem to find any information on the 68HC912D60A... you have a data sheet? or perhaps a site for them? Im assuming they are of Freescales creation?


Cheers