Autonomous Manumatic, decepticon spy

ciper · Post by **ciper** » Tue Mar 30, 2004 3:54 am

Im speaking to the guy now and will post information soon.

In basic terms he has disconnected the connections to the transmission and with the addition of a few diodes and connectors from the junk yard created a fully manual automatic transmission.
This is how he uses subaru autos for sand rails!

I was going to create a slightly more complicated box to handle reduced line pressure at low throttle and TC lockup between every shift, he has proven it to be possible!!!

MY92 · Post by **MY92** » Tue Mar 30, 2004 5:50 am

Like a manual shift kit?

Or would you still be able to drive this car like a full automatic with the flick of a switch?

ciper · Post by **ciper** » Tue Mar 30, 2004 6:50 am

If you got one of those old manual parralel port switches I guess it would be possible. There are alot of wires that your disconnecting.

To understand this easily, as referred to by the title the transmission becomes electronically disconnected from the car.

The only modification to the car side is a button to switch from "Drive" to "Park" signals sent to the Neutral/Park Key interlock+starting+cruise operation. So you press the button and the car thinks your in park and it lets you take the key out or start it and release the button for driving and cruise control. (if that made sense)

The car will stay in whatever gear the shifter is in no matter the speed. So if you choose 3 and your not moving the car will be VERY slow. Same thing, if you choose 1 at 80mph the engine braking effect will most likely shoot you up around 15k rpm (acura rsx style). This also means you can bounce off the rev limiter (if you have one) for as long as you want.

I need to look at my service manuals. There are something like 24 wires from the transmission. I guess many of them could be left connected to the TCU and with say 10 relays or so be able to go from normal operation to full manual mode.

Imagine this. Get a 5MT pedal set and wire the clutch pedal to press a switch. With clutch out the TC is locked. With clutch in the TC unlocks! A full 1:1 connection and soft shifts. The wild thing is that you would have to clutch in order to drive around town normally. I bet the gas milage would increase BEYOND that of a 5mt too.

On a side note I have found a 99 RS auto for sale with only 37k miles! This is the last year of the Gen 1 transmisisons (like ours) with 4.44:1 final gearing

Only problem is that its in PA.

THAWA · Post by **THAWA** » Tue Mar 30, 2004 7:31 am

some more questions for whenever you get back. Whats wrong with leaving the park/neutral switches alone and simply bypassing the tcu? that way you can still have the same selections work. Dunno if that'll work though, just throwing it out there.

Would you do something about the whole having to press the shift buttonto shift into 2 and 1? or would you leave it alone so you dont accidentally overrev.

About the clutch pedal idea, leaving the TC locked makes the revs lower yes? Would you be able to have the tc locked in all gears? Doesn't it make the tranny work harder at low speeds to have a locked TC?

What will this do to the MPT clutch system? Seeing as how the TCU controls this (AFAIK) will it basically be forced into 90/10 operation all the time or would it still be able to vary the distribution. Maybe you could instead of using the clutch pedal as a tc lock/unlock control you could use the clutch pedal as a sort of DCCD? The more you press it the lower voltage duty solenoid C sees which makes it less fwd based. I dont know how easy this will be either.

What will this do for stoping? Like if you stop in D how wil the car react to this? Will it work just like it did before or will you have to shift to 1 just to slow down?

I think that's all I have to ask for now

HAH just thought about being able to switch from regular to manual. Use the manual button! hmm but then you wouldnt be able to switch out of manual mode when the tcu is controlling the tranny, nevermind

BAC5.2 · Post by **BAC5.2** » Tue Mar 30, 2004 8:18 am

So when driving the TC would always be locked?

How are you going to idle?

THAWA · Post by **THAWA** » Tue Mar 30, 2004 3:14 pm

I'd assume you "clutch" when you come to a stop, which kinda answers one of my questions.

ciper · Post by **ciper** » Wed Mar 31, 2004 12:41 am

"leaving the park/neutral switches alone and simply bypassing the tcu?"
Yup, cant figure out why I didnt think of that

"press the shift buttonto shift into 2 and 1"
If in 1 you can slide to 2, if in 2 you can slide to 3. Downshifting is the only time you have to press it, and I see that as a good safety measure against overreving

"tranny work harder at low speeds to have a locked TC"
Tranny and engine. This is only a problem when you are below 20MPH (ive driven with locked TC a couple times)

"MPT clutch system?"
When electronically disconnected its a 1:1 connection, not a problem except for tight turns. I may run it at say 10% to allow a small amount of slip.

"What will this do for stoping? Like if you stop in D how wil the car react to this? Will it work just like it did before or will you have to shift to 1 just to slow down? "
I have to test the engine braking. Leaving the car in d and coming to a stop will make it VERY hard to get moving again. Shifting into 1st before you stop moving will either have engine braking which will throw the car around or it will coast.

Normally (in d 3 or 2) the car has engine braking in every gear EXCEPT 1st. Only when the shifter is in the 1 selection is engine braking active in 1st gear.

The guy Im talking with has a twin turbo ej20 engine (running single turbo) with link engine management. The engine is mounted in the middle of the vehicle with the front driveshafts of the transmission running the rear wheels. He is currently only running 8 psi of boost!! The tail section of the transmission is capped off and it has a 4.44:1 final gearing.

THAWA · Post by **THAWA** » Wed Mar 31, 2004 4:55 am

ciper wrote:"press the shift buttonto shift into 2 and 1"
If in 1 you can slide to 2, if in 2 you can slide to 3. Downshifting is the only time you have to press it, and I see that as a good safety measure against overreving
"MPT clutch system?"
When electronically disconnected its a 1:1 connection, not a problem except for tight turns. I may run it at say 10% to allow a small amount of slip.

Sorry that's what I meant about changing gears

What do you mean by 1:1 connection? would it be like a 5mt where it's always 50/50 f/r?

ciper · Post by **ciper** » Wed Mar 31, 2004 5:01 am

No, I mean 1:1 as in they always spin at equal speed no matter the amount of torque difference.
The non VTD 5mt with 10kg unit is a joke without an upgraded viscous coupling.

THAWA · Post by **THAWA** » Wed Mar 31, 2004 5:07 am

okay so what does that mean for power distribution would it be the same as a regular 4eat 90/10 or would it be like a regular 5mt 50/50 or would it be something completely different? and what always spins at equal speeds?

ciper · Post by **ciper** » Wed Mar 31, 2004 5:17 am

It would be NONE of those.

The output to the front wheels and output to the rears are locked together, 100% torque can go front or rear.

THAWA · Post by **THAWA** » Wed Mar 31, 2004 5:19 am

I still dont get it, when you are driving down the highway whats the split? when you are just starting whats the split? I'm assuming the TCU controlled the mpt clutch system, is that right? So if you disconnect the tcu from the tranny what is now controling the system? How does it know where to route power?

ciper · Post by **ciper** » Wed Mar 31, 2004 5:22 am

Dammit. When disconnected nothing controls it. There is no split.

Imagine the front and rear "driveshafts" being welded together.

THAWA · Post by **THAWA** » Wed Mar 31, 2004 5:24 am

so then both axels get full power right?

ciper · Post by **ciper** » Wed Mar 31, 2004 5:26 am

I think you understand, just not the right terms, both differentials get equal speed no matter the load.

If you had two open ones (front and rear) you could sping one front wheel and one rear wheel at the exact same speed. Throw in a rear LSD and it gets harder.

Basically the car would act like a 4WD truck in 4hi

THAWA · Post by **THAWA** » Wed Mar 31, 2004 5:28 am

so how is this not like the 5mt system?

ciper · Post by **ciper** » Wed Mar 31, 2004 5:29 am

Because the 5mt is a peice of crap unmodified. You can lift one side of the car up, lock the ebrake and a single front wheel will sping like mad.

THAWA · Post by **THAWA** » Wed Mar 31, 2004 5:32 am

okay I get that much, but I'm only really trying to figure out power distribution, not trying to find out which is better than the other.

BAC5.2 · Post by **BAC5.2** » Wed Mar 31, 2004 8:48 am

So if it acts like it's in 4-hi, what are you using to absorb the driveline shock? Seems like you would be putting a LOT of unnecessary stress on the driveline components.

How fast will the shifts be?

How will you downshift without upsetting the weight balance?

Is this supposed to be a 5MT replacement?

ciper · Post by **ciper** » Wed Mar 31, 2004 8:50 pm

"How fast will the shifts be?"
With the simple setup shifts are too fast (if thats possible). Even with racing tires and his car at only 8 psi it would chrip the tires from 1-2 and 2-3.

"How will you downshift without upsetting the weight balance?"
That needs to be tuned out, with this setup it will be fine on numerically upshifts (1-2) but bad on down (2-1), like dropping the clutch constantly

"Is this supposed to be a 5MT replacement?"
Sort of, some people want the fastest possible straight line speed. Some want an automatic with aftermarket engine control that isnt compatible. Some want the auto without any electronics.

Personally I want to find a way to create a full manual controlled transmission with the benefits of 0-speed boost, powered wheels between shifts, quicker shifts, predictability etc..

"trying to figure out power distribution"
The % of power depends on load, the speed of the front and rear differential will always be equal no matter what you do. Meaning if you pulled the parking brake and had the front wheels up in the air 99% of the power would goto the rear, but the front would spin at the same speed.

THAWA · Post by **THAWA** » Thu Apr 01, 2004 2:10 am

Okay we're not getting each other. I understand that the differentials will be equal (does this by definition mean 50f/50r or something else?) but for normal driving i.e. driving down the highway at say 70 mph no turning, no wheels slipping, no rain, no sand, no snow, no nothing, what is the power distribution? Sorry if this is getting annoying :\

ciper · Post by **ciper** » Thu Apr 01, 2004 3:10 am

The power would probably be 25% to all four wheels, same with the automatic normally and the 5 speed.

THAWA · Post by **THAWA** » Thu Apr 01, 2004 3:26 am

thanks

but isnt the auto normally 90/10 unless it slips or is put into 1?

ciper · Post by **ciper** » Thu Apr 01, 2004 3:28 am

Not really, if the amount of torque difference between the front differential and the rear isnt enough to overcome the friction of the clutches its still splitting power evenly.

I think subaru says 90-10 to make it easy for non mechanical people to understand. When fully locked it isnt 50-50 power either, since they both depend on the amount of load.

Imagine if the center differential was totally unlocked (fwd fuse), 100% goes to the front right?
Well now put the rear of the car on some type of rolling platform so the wheels arent touching the ground. The front wheels will pull the car, and the TCU will detect the rears not spinning and tighten the clutches up. No matter what the center differential does 100% of the power still goes to the front. (minus whatever momentum spinning the floating rear wheels may have)

BAC5.2 · Post by **BAC5.2** » Thu Apr 01, 2004 7:57 am

Won't the auto-come-manual suffer from the weakest link in the tranny (since the TC has been permanantly locked, this would leave the clutch-packs).

With every shift, ALL of the pressure of the power from the engine and the driveline shock will be absorbed by the clutch-packs. I can't imagine that this is going to last a very long time.

hmm, what other concerns do I have....

25% to each wheel, so Locked diff's? Or is it 50/50 front/rear, and open L/R?

Are you going to set it up to be paddle style, or just use the shifter (push it forward for upshift, and pull back for downshift). I forsee over-shifting to be a problem (in all the excitement, shifting up twice). Will there be a safe-guard style thing to prevent this?

This sounds like a great idea, assuming there is no shift-lag. I would never use it (I like turns more than straight lines. If I wanted a drag car, I would have gotten a different car), but it sounds damn interesting. I'd just be worried about the durability of the whole system. You are basically side-stepping the clutch on EVERY shift. That is a LOT of driveline abuse.

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Autonomous Manumatic, decepticon spy

Autonomous Manumatic, decepticon spy