PorKen

That would be cool, but a (remote*) clutch servo would just make it easier to push in the clutch. I imagine it would (will?) make it easier to feather as well.

Even though the S4 is more powerful, I favor driving my BMWs in the city now because their clutches are so much lighter.

I might actually think of keeping this S4 (vs. getting an auto) if I could make town driving (which I mostly do) more enjoyable.






*the stock hydraulic line from the clutch master is plumbed to the servo, a new line goes to the slave

Socal_Tom

Good discussion, fun topic.

Question-if my car starts in first gear from a dead stop that suggest that the transmissions already had a shift kit or some sort of modification done, correct?

GT6ixer

Nope. That's how they are supposed to work. At least that's how S model trannys work and as far as I understand the S4 is similar in function. Place the gear sector in "2" and from a stop the car will start out in 1st gear and then shift early (~4800 RPM) before redline into 2nd automatically. From there you need to manually push it into 3rd before redline and then again into 4th before redline. If you push hard on the gas pedal as to engage the kickdown switch the shift from first to 2nd will happen later. Mine shifts at about 5500 RPM doing it this way. I have read from others that theirs shifts to 2nd as late as 6200 RPM with the kickdown engaged.

Here is a thread I started about this.

https://rennlist.com/forums/928-foru...ft-points.html

I posted this before I had my throttle cable adjusted by Colin. He estimated I was only getting to about 60% WOT. I need to go beck and update these numbers now that everything is properly adjusted.

Landseer

Actually, the modification of S4 transmissions to begin in 2nd gear occurred partway into the 87 production run.

Captain_Slow

I'm still confused about the proper way to "manually" shift the auto. But at stops I pretty regularly pull it from D back to 2 and back to D to force it to start off in 1st, and it also revs higher in each gear...a lot higher. Chirps the tires on the shift to second. It's fun. The S4 has a nice low end that is hidden by the normal drive mode. About 4500? rpm or so the flappy opens and it's like second stage ignites. I usually get scared at this point because at this point my speed is automatic reckless driving in Virginia. So I let off but the car feels like it can just pull forever. It's not really "sports car" kind of power and torque. To me it feels deliberately intended for Autobahn cruising...producing a steady pull up to 120+ mph cruising.

2002M3Drew

I thought all of the M-B 4 speed autos start off in 2nd if you start from a stop in "D" or "3."

Socal_Tom

I did too, was there short run where they didn't?

Edit - mine does this when left in drive.

Socal_Tom

Virginia doesn't mess around with tickets if memory serves.

GT6ixer

Do you mean "2" instead of "1"? I didn't think there was a 1st gear selection.

My '84 starts out in 2nd when in "D".

docmirror

I started my 928 life with a 90GT, close ratio high final drive 5 sp. When I got the 86.5 with 1st gear start mod, I realized the outstanding trans operation of the 928 auto. I have had an 89, and now have an 88 auto and looking forward to some more shift-no-clutch driving again. The MB auto is well suited, and well designed for the S3 and later cars. I don't mind rowing the 996, but the 928 auto is a joyful trans method.

Landseer

Oops double post, sorry

Landseer

My '84 starts out in 2nd when in D


Then your 84 needs adjustment, when out of adjustment it will exhibit 2nd gear start. We can discuss and debate, but at the end of the day the transmission should start on first from a stop when in D... neither installation of the shift kit that strengthens the 2/3 and 3/4 shifts, nor the B2 piston upgrade will affect this fact on 84,5,6, 6.5, or early 7 transmissions. BTW, the kit service parts mentioned fit all the 4speeds. The second gear start for the later S4 was actually a shift program change, ie, a (minor) change to the hydraulic logic in the valve body.

See attached word file excerpts from the 1988 MY service documentation. It states that the change to 2nd gear start ( under normal acceleration ) was slowly phased in during the 87 production year, and that prior 4 speeds all utilized first gear start.



( not trying to be a know it all, but spent my first 5 years in this sport reading the Morehouse CD ancillary obscure wsm documentation in order to fix t neglected cars. Had to do quite a bit of study to attempt to repair an 84 with broken parking panel and cracked case. Ended up replacing with an 89 that does start in second. Have forgotten lots of it, but this piece I remember.)

FredR

No idea what the earlier models were designed to do but for the S4/GTS generation they were designed to set off in second gear with normal driving. Mash the pedal and they should set off in first. This assuming they are set up as per factory instruction.

Tighten the kick down cable about 4 turns and first gear starts become the norm. By-pass the kick down switch and they for sure start in first gear every time even with gentle throttle pressure so it was still user friendly as it were.

Whether or not such impacts the longevity of the transmission remains to be seen. If the box could not take starting in first there would be something wrong with it. Hoon around in the car every time you get in it and you deserve the consequences- everything has its limits. Be sensible and I am confident it will serve you well.

I have a selector switch on the kick down by-pass- rarely do I use it in normal kick down mode.

Landseer

Well Fred, I agree with everything you mention above.
Except the bolded isn't true for the early S4.


For the poster above having trouble with the improper 2nd gear start from an 84 transmission, be sure to read the A28 troubleshooting guide and the A28 description of operation guide. It is located on the CD in a transmission specific folder.

Captain_Slow

Oops...you're right. D to 2 then back to D will launch in 1st gear and hold gears longer (to redline if you stay on it).