Gearposition sensor(s)?

[Loupoz]

Hi R3V.

Has anyone ever fitted some sort gear position sensor to a manual BMW gearbox?

I know there is a SMG version of the ZF GS6-37 that has to sensors on top, it just looks like the casting is different from the normal one, still might be an option?

Or the position sensor from an E46M3 with SMG, maybe some1 converted that to a manuel some way?

[TobyB]

Nope, I've never done that.

Rumor has it that the E46 and later does it in software
to adjust neat things like 'anti- jerk', throttle responsiveness, etc.

Why do you ask?

t

[Loupoz]

Nope, I've never done that.

Rumor has it that the E46 and later does it in software
to adjust neat things like 'anti- jerk', throttle responsiveness, etc.

Why do you ask?

t

Because i want a stand alone ECU to drive my S38 with DBW and then be able to do downshift revmatching, like a new manual BMW.

[e30davie]

Years ago a fried of mine used a series of micro switches and a picaxe micro controller to display the gear on the dash. lots of trial and error required and quite a few iterations in design. Must note that he was playing with a FWD car so he had the gear stick "carrier" to bolt all his micro switches too.

I think on a getrag 260 and similar with the remote shifter mechanism, perhaps you could look at attaching position sensors to the shifter rod that go between the gear stick and the gearbox. Would have to create some sort of bracket off the gearbox itself. You've got 3 "in and out" directions to track, and if you only did forward gears you have 3 "side to side" directions. 4 if you want reverse too. (assuming the reverse is up to the left like a g260). Then youve go to interface your new electronics project with your ECU.

All gonna be custom and fiddly and in a very difficult place to be working.

[nomansland92]

Most stand alone ecu's have gear detection built in just by mph vs rpm, not sure if that would work or not for you though.

Sent from my SM-G892A using Tapatalk

[Loupoz]

Most stand alone ecu's have gear detection built in just by mph vs rpm, not sure if that would work or not for you though.

Sent from my SM-G892A using Tapatalk

Yeah i know, but it needs to know what gear its going into, to be able to rev match. The way youre describing "discovers" the gear after youve gone into it, and released the clutch.

Years ago a fried of mine used a series of micro switches and a picaxe micro controller to display the gear on the dash. lots of trial and error required and quite a few iterations in design. Must note that he was playing with a FWD car so he had the gear stick "carrier" to bolt all his micro switches too.

I think on a getrag 260 and similar with the remote shifter mechanism, perhaps you could look at attaching position sensors to the shifter rod that go between the gear stick and the gearbox. Would have to create some sort of bracket off the gearbox itself. You've got 3 "in and out" directions to track, and if you only did forward gears you have 3 "side to side" directions. 4 if you want reverse too. (assuming the reverse is up to the left like a g260). Then youve go to interface your new electronics project with your ECU.

All gonna be custom and fiddly and in a very difficult place to be working.

Yeah if i had a FWD gearbox, just setting up a bunch of proximity sensors on the input levers would be faily easy. Or strain gauges on the linkages, so they know if youre pushing or pulling.

I do believe the E46M3 SMG gear position sensor might be able to do the trick, i just cant get the idea co connect it to the linkage. An on SMG gearbox it sits at the very back of the actuator.

[TobyB]

Years ago, for a very different project, we did something like that at work
with a tachometer sensor on the transmission INPUT shaft.
It was an electric drive, but the principle's the same:
if your ECU knows the speed the input shaft on the transmission's spinning,
it can 'simply' match the engine to that.
So if you were, for example, moving in 3rd, and selected 4th, the engine would
drop to match the slower- spinning trans.
But if you selected 2nd, the engine would be instructed to rev up to match
the now- faster spinning trans.

We spent some real time on software to get it to work, and eventually
had to invest in a better motor drive, but it did work well once the bugs were
ironed out. I didn't have much to do with coding, but it was NOT trivial...

one idea,
t

[The Dark Side of Will]

Yeah i know, but it needs to know what gear its going into, to be able to rev match. The way youre describing "discovers" the gear after youve gone into it, and released the clutch.


Yeah if i had a FWD gearbox, just setting up a bunch of proximity sensors on the input levers would be faily easy. Or strain gauges on the linkages, so they know if youre pushing or pulling.

I do believe the E46M3 SMG gear position sensor might be able to do the trick, i just cant get the idea co connect it to the linkage. An on SMG gearbox it sits at the very back of the actuator.

I guess you still want to shift manually?
The E46 SMG hardware should work on the E34 M5 3.8 420G transmission...

[The Dark Side of Will]

If you just want gear position sensors and you have access to the ends of the shift rails, you could use travel switches to figure it out... Each rail would need three positions: forward, neutral, rear. Only one rail will be out of neutral at a time, though.

[Loupoz]

If you just want gear position sensors and you have access to the ends of the shift rails, you could use travel switches to figure it out... Each rail would need three positions: forward, neutral, rear. Only one rail will be out of neutral at a time, though.

Yeah i want to still shift manually.

Im not that strong in transmission internals in english, what are shift rails?

[The Dark Side of Will]

The thing that the shifter operates is the shift shaft. Inside the transmission, the shift shaft has a fixture that operates shift rails.

Each gate in the shifter operates one shift rail. There's a rail for 1-2, a different rail for 3-4, etc. A shift rail is just a metal shaft. At one end it has a fixture that interlocks with the fixture on the shift shaft so that when you move the shifter forward/back, both shift shaft and shift rail move. One the other end the shift rail has the shift fork, which moves the shift collar back and forth. The shift collar is what locks the gear you're in to the output shaft.

There is a mechanical assembly called the "detent" that ensures that when one shift rail is moved from neutral, none of the others can be moved out of neutral. The "detent cover" on a Getrag 260 is the part of this assembly that's visible from the outside of the transmission.

[Wanganstyle]

Gearposition sensor(s)?

Try aftermarket; I’ve never used this myself but do know devices like this can work.

https://auto-blip.com/auto-blip

Had a student with a similar aftermarket device installed in modern gt350r.
Wasn’t as good as a human rev matching properly; was better then no rev matching at all though