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PostPosted: Sun Jan 18, 2015 7:58 am 
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Joined: Tue Jan 07, 2014 6:34 pm
Posts: 12
Hello everyone, I'm looking for some twinstick knowledge.
Does anyone know what the exact chassis code and models that came with a twin stick transmission?
Or what the exact transmission model is that used this arrangement? Or was there more than one?

The reason that I am asking is because I am in the process of rebuilding and modding a km182 out of a 1990 colt vista. It is the 5spd manual awd transmission. An interesting note is that I have found out that a fwd 2g dsm front differential will interchange as I have just installed a wavetrac in mine. The axle situation is a little more complex but in case anyone else ever is working on one of these transmissions and is curious the bigger spline fwd dsm front diffs interchange and the small spline awd ones should as well, I was just personally looking to put bigger axles in my car. The stock colt axles would fit an awd dsm aftermarket front diff. I've put awd front axles in and they fit, the splines I mean, not the length of the axle for the chassis.This means the awd dsm front diff will work with stock colt axles.

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Anyways my question about the twin stick is because of what I see in my transmission and what I've read about the twin stick system. I say read because I've never actually seen one in person. My transmission accomplished 5th gear by changing the ratios of the intput shaft to the intermediate shaft. This is done with a vacuum actuator controlled by an electric solenoid. From playing with the transmission if this was controlled manually it will split all the gears giving an 8 speed transmission. Much like a twin stick. Heres a pretty shot of the vacuum system.

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Quote:
It offered a choice of final drive ratios, and changed the effective top gear (fourth) ratio between 1.11 to 0.86 to 1. Why Mitsubishi thought this might be better than a simple five-speed with overdrive fifth gear is long lost in the collective memory. It did mean that all the gears were either lower or higher; hence the “economy” and “power” ratios. Or you could split them like a truck driver and play with all eight. That involved a few redundant overlapping ratios, but hey, in the days before texting, it was a way to keep the mind and hands busy. You know the old saying about idle hands…
from
http://www.thetruthaboutcars.com/2009/1 ... uth-champ/

So I am wondering if there is an existing stock shifter assembly that I could use for this, or at least model my custom one off of. I could pretty easily modify the wiring to the vacuum shifter to make it run off a switch and as a safety have it run off a relay from the clutch switch so it won't try and unrelentingly shift while still in gear accidentally but I sort of like the simplicity and fun of two manual shifters in the car. The vacuum crap scares me a bit honestly, I get how it all works now but if that gets into neutral there is no power going past the input shaft, and the system is complex and old, it relys on rusted vacuum canisters/actuator, an old rubber diaphragm in the actuator and sensors and an electric solenoid I am almost sure I would not be able to source a replacement for. My second gear synchro was the last one in the country according to JNZ. Soooo a manual shifter has a certain appeal.

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You can see the actuator part #s 1-5 in the top right of this page,
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And the actual shift rail inside the transmission itself. All but 3-4 shift forks are steel in this transmission.
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The other system is the 4wd engagement. This transmission has no center differential. There is a directly driven output shaft from the front diff ring gear which is coupled to the GIGANTIC transfer case input (diagram 17) with another shift assembly. The rail(22), STEEL fork (23)and locking ring (15). Same diagram as above but look towards the bottom.

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The thing is this is all just locked in on my transmission. There is an enormous viscous coupling in the middle of the driveshaft going to the rear diff to allow full time 4wd with no center diff. I believe earlier models did have a shifter here, I am also considering applying the same concept here as well, if there is a stock shifter assembly and different cover that i could use or model based on a stock system to manually engage 4wd as well.

Again if anyone has any info about what model or chassis codes here to look up ASA stuff will help me a ton.


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PostPosted: Sun Jan 18, 2015 11:01 am 
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Spends Too Much Time Under The Hood

Joined: Tue May 06, 2014 8:23 pm
Posts: 342
Location: Orlando, fl
Those transmissions are awesome, all I know about is heavy duty truck transmissions which are air actuated. I hope you find what your looking for you can try www.mirageforums.net if you havent already

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91 Summit hatch "Sunchaser" R.I.P.
94 Mitsubishi Mirage "4dr"
06 Kawasaki Ninja 250r "daily driver"


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