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Discussion Starter · #1 · (Edited)
I was thinking, our auto tranny is computer contorolled. The computer tells it when to shift. I was wondering if there was a way to let the engine rev to redline before it shifts to the next gear for racing. I thought why can't you just make some electronic switches to shift the tranny when you want like the sportronic mode in the new eclipses.

I searched the DSM forums because I knew their auto trans would work similar to ours. I came up with this:

http://www.dsmtalk.com/forums/showthread.php?threadid=62012&perpage=25&pagenumber=1

Someone there already did it! They set up push button switches to activate the solenoids.

Why don't we do something like this for our cars? We could use the shifter from a sportronic transmission out of a new eclipse and stick it in our console. Then we could hook it all up to shift the gears manually. We could have a swithch that lets it work like a regular automatic, or switch to sportronic mode.

So can we do it? Someone with some in-depth electrical/auto tranny knowledge should develop a kit we can buy. Who else here wants something like this? Lets get the ball rolling! :D
 

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I've tried

I've been trying to figure that shit out for MONTHS. I've talked to computer chip guys, transmission builders, engine builders, Mitsubishi, Matt at Dynamic Racing, and NOTHING so far, absolutely nothing, I love my level 10 transmission in my Diamante but haven't been able to figure anything out to make it shift later. I still gotta call Matt back because he said he would find out about the Diamante transmission computer. He already told me that there was no break through yet for the 3/S auto and said he would get back to me on the Diamante. You're theory sounds good but if it was possible I think so many people would have jumped at the chance to do it for me since Im willing to pay big bucks. I don't know bro, I hope you figure somethin out.
 

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this is just a ideal but if the auto tranny is computer contorolled then why not find the computer if it not the ecu and re-program it to where it would shift at a higher point....
 

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Discussion Starter · #4 ·
Well if you read the thread at the DSM forums, the guy just found the wires going to the solenoids and hooked them up to switches. He was able to manually shift the gears, but the shifts were very fast and violent. There are also controlls to lock or unlock the torque converter and some other stuff that I'm sure makes the shifts softer. Is this just not possible with our autos? They are both electronically controlled mitsu trannys, they should work the same. I think there was even a comercial kit for the DSM autos that did this, I think someone said they were like $1,100 though. I don't know enough about it to actually go out and do it from scratch, but lets keep thinking about this. I know it could be done. Even re-programming the stock ECU to shift at a higher point during wide open throttle would be awesome.
 

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why don't you just put it in first then wait till it hits redline and shift. I'm pretty sure it works. I know i've hit redline a few times in my auto.
 

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Hey tajman_17,

That's a great idea man! ur one of the ATX Assets around here. Keep me updated man.
 

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Discussion Starter · #8 · (Edited)
dirtypimp1 said:
why don't you just put it in first then wait till it hits redline and shift. I'm pretty sure it works. I know i've hit redline a few times in my auto.
This would be a different than manually shifting your auto (putting it in L then 2 then D). That causes tranny damage. This would just replace what the computer is doing normally by shifting to the next gear.

I'd like to hear from Frank @ Kormex if he does it all the time. I know it can be done, and its one more thing that brings us closer to the performance of the 5 speed. I have heard that the actual gearing in the automatic is better for 1/4 mile racing than the 5 speed is. A higher stall converter and a shift kit really closes the gap between the auto and the manual, this will take us one step closer. The fastest drag cars in the world are automatics, ours can be too if we put the time and money to develop them.

Someone on here said that a guy running NOS on his auto was pulling better times than a manual with the same shot of NOS. I really believe the potential is there.

Also remember that the FWD 5 speed has different gearing than the AWD 5 speed. The FWD manual is not geared for 1/4 mile racing at all. The manual may be geared better on the AWD cars, but I think the auto is geared better for the FWD cars.
 

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Discussion Starter · #10 ·
Is the auto tranny controlled by the main ECU or by a seperate auto tranny computer. When I was asking about a TT conversion on the automatic, someone said you couldn't use the TT ECU because it would not support the automatic. You would have to use the stock ATX ECU and get aftermarket controllers for the fuel, etc.

If we do this, we could use the sportronic shifters out of the '00+ eclipse or the dodge stratus. The guy that did it on his DSM had some pushbuttons down on his console, but a real sportronic shifter would be awesome! Just push forward or back to shift up or down.
 

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don't manually shift, that cause major damage because when you're in between shifts, the trans ECU is not reading shit and therefore not sending fluid and causing your trans to over heat
 

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Discussion Starter · #13 ·
I sent Frank a PM.

That other thread was kind of negative. Everyone said it would serve no purpose because the tranny already shifts at redline if you get on it. This isn't true at all. Go ahead and floor it in your auto, it will shift well before redline. Also, with upgraded valves and springs you can set you can safely rev well past the stock redline. A car thats supercharged or turbocharged is going to have different peakes for HP and torque, I believe this will GREATLY improve the auto performance. Frank said himself that he had done it and it worked great. I'm excited to see...
 

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My ATX shifts at redline if it is in pwr, with od off, with WOT. If I get off the gas at all, it will shift earlier. My trans is completely stock, afaik.

The ATX definately has a separate Transmission Control Unit. The problem with the turbo upgrade is that the turbo ecu won't send the necesarry data to the tcu.

I would love to set up a push button system or something like that, simply because I don't like the look of the ATX shifter. As far as manual shifting goes though, it defeats the benifits of the ATX. The reason they are faster is because the computer can react faster than a person. The solenoid doesn't have to wait for your hand to move. If the shift points need to be modified, then a new controler needs to be created. What I would like to see is a fully programmable TCU, where you can set your shift points based on throttle position and rpm, just like the stock points are set, but make them movable.

I have no doubt that I could write software for this, but I don't know how to make it embedded but still programmable on the fly. I don't want to have to wait for my PC to boot to drive my car.
 

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Discussion Starter · #15 ·
imetis said:
As far as manual shifting goes though, it defeats the benifits of the ATX. The reason they are faster is because the computer can react faster than a person. The solenoid doesn't have to wait for your hand to move.
This is not correct. In a manual tranny car, pulling the stick actually switches the gears mechanically. Thats why it takes longer to shift. With this setup, the sportronic shifter stick is just an electronic switch that tells the tranny computer when to shift. It will shift just as fast as a stock auto, and you can use a shift kit to make it shift even faster. Have you even driven a sportronic transmission car? It doesn't pull it out of gear when you pull on the lever and then put it in the next gear when you reach it with the lever, You actually push back or forward to shift and then you feel the computer shift the tranny a half a second later.

There would be many benifits from this setup. Say you are racing from a roll agains a manual car. They can downshift and drop the clutch right when you hit it, but in the automatic we have to floor it and wait for the computer to downshift a second later. With this we can drive in a lower gear at a higher rpm when the auto would have regularly shifted already. It just gives you complete controll of your auto just like it were a manual, and it still shifts faster than any manual can.
 

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I think that there must be an ECU programmer out somewhere. On my chevy pickup I used hypertech power programmer which would let me change every single bit of parameters in my computer including shiftpoints and rev limiter.
I believe our cars should work the same way. There must be a factory progrmmer that would "reinstall" ECU software in case its messed up. I don't know anything about 3s ecu's but unless it is read-only, there must be dealership that could change the information in it.
 

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This Sounds Like a Great Idea, But....

First, the gearing on the FWD manuals is taller than it is for autos, so all else equal the manuals are geared better.

Second, the ECU controls the shift points. My JET chip did a few things for me -- reprogramed the shift points to shift at higher rpms (when I get on it), advanced the timing, and caused a richer air/fuel mix. Why not just reprogram the ECU to shift at nearly redline when you stomp on the gas -- isn't that what you're getting at anyway? That can be done, and it already has been.

I got the JET chip and the K&N FIPK at the same time, they were my first mods. They gave my car some balls. I've heard some negative things about JET chips, but all in all I'm pretty satisfied with mine.

Having said that, being able to manually shift an auto would be pretty cool! I'd be interested in hearing more about this Eclipse guy....
 

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Jet

I spoke to a guy at Jet Perfomance Chips and he told me straight up hell no he won't change my shift points, I was like I'll pay yuo good he was like no, only fuel and timing, "we don't mess with shift points".
 

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Re: Jet

SamAlam said:
I spoke to a guy at Jet Perfomance Chips and he told me straight up hell no he won't change my shift points, I was like I'll pay yuo good he was like no, only fuel and timing, "we don't mess with shift points".
:( :( I would love my car to see 7300RPM too. ;) My auto shifts me at 6500RPM all the time during WOT. Taj -- I've been able a few times to shift at a higher RPM by just staying in Low. I know I know it's horrible, it's horrible, but if your able to time it right it'll work. You can at least see if your engine will hold power past the redline. What if your powerband dropped off at 6800, all this work your talking about wouldn't even be worth it. My car pulled as hard, and possible even harder until about 7200. I think the only mods that really helps up there are the K&N and the test-pipe. Anybody know if autos have the same fuel cutoff as manuals in the N/A DOHC cars?
 

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In power mode my 95SL usually hits 7k if I floor it, I dont think its ever dropped at 6.5k, in higher gears it will hit 6.8k mostly. Is this common?
 
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