S50 + G260 in E30 Questions! Help pleeeease!

[ForcedFirebird]

Yeah well now there's 5 transmission s on the shelf since I pulled apart the package lol.

You would think it would still work since the pin was moved to the proper location, the 95e36m3 clutch package was just thinner overall than the g260 stuff when installed.

If the DM e36 FW won't work in a shallow trans, or this trans, what g260 does it work in?

EDIT: according to the thread this trans should have the bosses for the old style shifter, it does not.

[scottinAZ]

ok, according to the "Official Transmission Thread", that P/n goes for either early or late Eta transmissions, the difference being the shift carrier mounts (yours dictates late eta) and the depth of the bellhousing.

If I read you right, changing out the M3 clutch and fly to the M20 I unit solved the problem. if so, the issue may just have been in the shape of the package, and a lack of clearance in the bellhousing, however, if the pieces add up, then the trans you have is the deep bellhousing unit. Goes to show that when mixing and matching parts, sometimes things get mismatched...... ask me how I know this (shallow trans with dual mass, no workie either....)

[ForcedFirebird]

Getrag 260.0.1270.90

Says early eta, has the holes for CPS but no holes for the early shifter.

Had a spare motor/trans for my car with a new clutch, has the m20 "is" lighter FW, PP - put it in and it works now.

[scottinAZ]

Interesting. Out of curiosity, what is the P/N on the side of the transmission? if all is the way you say it is (and I have no reason to doubt you) then it should be working 4.0 by now. Im running out of ideas as well....

[ForcedFirebird]

As posted earlier there's another complete m3 setup in the shop, waiting to go in on of the other team member's e30. I took all measurements and matched everything up. TOB PP and clutch disk came as a kit and does match the other after changing the pin and slave rod.

[scottinAZ]

I assume you have independantly confirmed the correct TOB?? if the fork is indeed hitting the pressure plate you may need to use the euro TOB. how does the back profile of the M3 clutch pressure plate compare to the standard pressure plate? Is there a difference in part number with the M3 fork?

[ForcedFirebird]

OK. Got the car running, exhaust built etc. Had an issue with the DME grounding the fuel pump relay and temporarily tapped into the main relay to kick FP relay to test. As soon as clutch was in and a gear select was attempted the car lunged (no clutch still).

Pumped the clutch several times to make sure no air holes, started the car again, this time I heard the fork hit the pressure plate, still no clutch.

I'm stumped.

It's like the TOB is too short...

[Wanganstyle]

to add more confusion to the G260 puzzle;

my 04/87 eta had an ETA dual mass in it. true 228mm dual mass with same clutch compatiblity as m50 e36 (g250), dual mass had 2 reference marks on the back for the 2 sensors in the bellhousing.

replaced with a 325i compete clutch+single mass thin fly.

I have a thick eta early flywheel with reference sensor marks also here.

[scottinAZ]

Drilled the trans to accept ZF pin and pulled the slave rod out and put in a longer one. :)

Got it all together but the car doesn't run yet, have to figure out what else the previous mechanic did FTL. Started once, idled fine then wouldn't re-start, no fuel...

that will do it... hopefully the plastic pin will hold up over time (I replaced mine when I installed it) seems like a shitty place to resort to plastics....

[ForcedFirebird]

shouldnt take much to do. Make a custom pivot pin on a lathe, and maybe a threaded end on the slave cylinder for more adjustability.

Drilled the trans to accept ZF pin and pulled the slave rod out and put in a longer one. :)

Got it all together but the car doesn't run yet, have to figure out what else the previous mechanic did FTL. Started once, idled fine then wouldn't re-start, no fuel...

[scottinAZ]

shouldnt take much to do. Make a custom pivot pin on a lathe, and maybe a threaded end on the slave cylinder for more adjustability.

[ForcedFirebird]

Ok. Took both fork pivot pins out and measured the bell housing casting and they are the same from the g260 to ZF, but the pin is 1/4" longer...



Also the slave installed on both, relaxed/open, the ZF slave is 5/16" closer to the diaphragm spring than the g260.

~1/4" doesn't seem like much, but when we are talking about ~1/2-5/8" total travel, it's a lot.

Going to make an adjuster to get the pivot pin closer to the diaphragm and extend the slave rod, assemble it and see what happens.

[ForcedFirebird]

Took measurements of all the transmissions this morning. Forgot we also have a 97 s50 setup here, so took those measurements as well.

All the forks are the same. When assembled with the fork, TOB and slave (relaxed position) the TOB is ~1/4" closer to the diaphragm spring on the ZF's than it is on the g260's. This tells me there is at least 1/4" more for the slave to go on the G260 to meet the s50 PP - I say more since it is a lever and movement will be amplified.

[scottinAZ]

6 7/8 is the measurement for the slave on the deep bellhousing. as I said before, there are so many variations its hard to get a cohesive idea on what the hell BMW was doing. Deep bellhousing, dual mass fly, stock throwout and fork should have you in good form.

One other thing to check would be the shape of the pressure plate, if there is significant variation on the bellhousing side as opposed to the Eta/M50 plate there could also be problems as well, although a simple check of fork part numbers, and a visual on the PP should be sufficient to see if there will be an issue....

[ForcedFirebird]

Odd. My 10/86 eta had the single heavy single mass. I have no idea what trans this is but it does have the CPS locations indicating it is at least from an eta. My OEM trans has same dimensions but came with heavy single mass (bought the car with 70k miles). I gave up tonight and just got home. Will take more measurements tomorrow.