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Discussion Starter #1
We have some pretty smart peoples in this club so I thought I would ask.


We have a 1966 289 Mustang. Would like to install a 4R70 in it. Anyone have any ideas about the computer controls on this since it is a carb car?

I was thinking that we could stripe out all the engine controls and run the stock computer for just the tranny.

Ideas?
 

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I was thinking that we could stripe out all the engine controls and run the stock computer for just the tranny.
You're not going to be able to run any kind of factory computer to control the trans. The stock computer needs input from almost every sensor to calculate the proper shift points and line pressures for the trans. The most important are load (from the MAF or MAP) and throttle position (from the TPS), but the final timing calculations are also tied in with the transmission functions, and those are dependant upon coolant temperature, air charge temperature, oxygen sensor feedback, and RPM, among other things. You can turn off the auto trans function in a factory computer, but you can't turn off the EFI function.

Your best bet is the Baumann TCS (linked above) or something similar.
 

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I would much rather use a Compushift unit. Yes, I know, it costs a lot more. But, you get what you pay for and that comes complete with a lack of issues.

Darrin
 

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$1280 vs. $400.... I can live with some issues for $800. :D

IMHO it probably depends on the application. If you just need something simple for OD in a daily driver or weekend cruiser the Baumannator TCS would probably be fine. If you need something for racing, very high performance, etc., the Compushift would probably be recommended.

But that is just my .02.

I've heard great things about the TCS and I've heard some bad things (all dependant on the application). I don't know anything about the Compushift. :thumbsup:
 

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Lets clarify that a little more. On the Compushift you get everything you need for the one price. With the TCS you only get the controller for that price.

The issues we have seen have been transmission burning ones when they happen and it hasn't been only the racing or high performance cars that have had the problems.

As a matter of fact I have been given a couple of the TCS units because they pissed the former owners off so much.

I agree that it is hit and miss on how they work for people and I don't know why. It would be a great product for a low powered daily driver situation if you knew it would work before it destroyed your transmission.

I am not one to take that kind of gamble, but that's just me.

Darrin
 

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Three notes on the TCS just incase people purchase them.

1) Make sure your 0% Throttle value in the TCS software is far enough below the point where the throttle is physically closed so that it doesn't fall into negative values. Unlike factory computers, the 0%tps threshold will not ratchet down to it's lowest seen value.

2) Line pressure for low throttle needs to be a decent amount higher than the values in the "Premade tunes" they send you... I tried to start with one, and build upon it, and the transmission didn't feel right...

3) Make sure your SPEED in the TCS software is accurately adjusted. Test it with another car or two. This is very important, and will make life easier on you.

In my personal opinion, the TCS is NOT a good alternative, but it is a working solution that is neccessary in certain cases. Just like with tuning a motor, care and precision is manditory to make sure things hold togeather.
 

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Discussion Starter #9
pics of mustang or it's unpossible :D

I so missed this request. We are stealing my low mile AOD for a temp fix until we can decide where to go with this.

Tell me if the pic is too much. I'll resize it.




 

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Just rode ina 68 Stang witha 4r70w and a BE controller... fantastic setup... very streetable with OD and lockup... kicks hard... very consistent... overall fantastic setup.
 

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Hey guys, Consider this idea...

Use a General Motors MAP sensor instead of TPS input. This would give you a true load value.

EDIT: Did the math. I'm going this route.

GM 2bar map sensor has a voltage slope of roughly v=2.45+.17x ... X being PSI.

The lower voltage limit accepted by the TCS is .31v, with a 4.9v maximum, so you have anywhere between "-12.5psi" (Which is somewhere around 26 in/hg) and 14.31psi to work with....

The TCS has 10 steps in it's load table, and to make tuning easiest, it is helpful to have atmospheric pressure be one of the major axis.

The minimum voltage is going to be .31v (-12.5psi), so that we have as high of resolution as we can in the lower load ranges.

Given that, we need to find a step that will iterates up evenly to get to "0psi"... If you set the maximum tps voltage to 10psi, which is 4.15v, there is a 2.5psi step, giving you the following scale for load:

STEP--Volts---PSI
0_____.325__-12.5 (26in/hg)
1_____0.75__-10.0 (20in/hg)
2____1.175___-7.5 (15in/hg)
3______1.6___-5.0 (10in/hg)
4____2.025___-2.5 (5in/hg)
5_____2.45____0.0
6____2.875____2.5
7______3.3____5.0
8____3.725____7.5
9_____4.15___10.0

I'm sure you can do the same math for a naturally aspirated application.

This should gretly improve driveability, since, as load on the motor decreases, vacuum will increase, and a shift can be triggered. It seem much more logical than having to wait to achieve a certain speed, or modulate your throttle position in order to induce a shfit.
 
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