boeinguy2

Is the automatic that much stronger? That is odd. Seems like the other way around for the 300ZX. People who mod the TT motor seem to mostly have high performance clutches on a 5 Speed.

Fishy928S4

Ok, silly question from an owner of 2 auto trans S4's.

Drive it like a manual???? How do you manually shift an auto trans as some stated here? I guess you mean start in 3 and shift to D??? What are the shift points for best performance?? Isn't it bad for the trans to do this?

Bill Ball

The Mercedes 4 speed AT in the S4 models is awfully nice. The rather long throws on the 5-speed, even with the short throw kits, makes this not the quickest shifting manual. By traditional rules, the AT knocks the car out of the sports car class for most people, but it has a lot going for it. Shift it like a manual when you want to or let it do the shifting.

Jim bailey - 928 International

I have yet to see anything written where the actual strength of a 5 speed trans has been compared to an automatic. Much of the information is an inference from what applications the same basic automatic was used by Mercedes and tuners. The 5 speed when used in a race car at about 500hp 6.5 liters has broken on occasion BUT no automatic thus far that I am aware of has had that much abuse on a race track on race tires. Street driven cars simply never get used that hard...you are either in jail or dead far too soon.

drnick

to shift it like a manual, drop it down to 2 from drive and let it redline in first gear or when you want 2nd tip it forward and then back ie into 3 then back to 2, quite quickly. then if you want third change up to 3. want second again? change back down to 2. to get first you need to be nearly stopped or wire a kickdown bypass and activate that while in 2, it will change at under 20 mph.

when i was looking at 928s for the first time i found them incredibly intimidating from behind the wheel, mainly because they are so wide - compared to the ford i had then. i test drove a manual and could hardly cope with piloting the beast let alone changing gear, came away thinking that id be quite ok in an auto!

50k miles later and im converting my auto to manual but i know there will be times when i regret it..

Jim bailey - 928 International

GTS automatic drop the lever into 2 floor it ,it will be in first , as it winds out quickly move from 2 to 3 and quickly back to 2 it will shift to second wind it out move to 3 you get third ,move to D it shifts to 4. Then you realize you are going 140 mph !!

bigs

Whoa. Wait a minute. In my AT, if I drop the shift lever down into 2nd at a stop, it does indeed start out in 1st gear. But I don't have to move the lever at all to make it shift from 1st into 2nd. The 1-2 shift happens automatically at redline. From there, I do have to manually shift it into 3rd and 4th (drive). Is this unusual?

boeinguy2

I am baffled also. The experience of younger days reminds me of the automatic transmission I destroyed trying to shift it as if it were manual.

mspiegle

i wonder how many AT cars have been used in very high-toruqe situations vs MT cars. Sure, some of the track racers with more power are breaking the 5spds, but maybe we only see the 5spds broken because that's all they use?

with regards to the 5spd on the 928, i really like the "dogleg shift pattern" (not sure as to the actual name, but this is what BMW guys call it). I think it is far superior and efficient to the standard shifting pattern on most cars.

Also, I think that the 5spd feels way more direct and instant. I know when I drove Andy's car (AT) around with his prototype setups, it felt nothing as lively as my car does with a similar setup and 5spd.

Bill Ball

The shift program was changed several times over the years.

T Colvin

Can some one equate Gear 1, 2, and 3 to speed?

blau928

Mike,

AMG, Brabus, and Mercedes have made enough cars with this transmission that have more than 400 HP/TQ than 928 race cars. In addition, many of the autos run at a higher consistent rate of speed in europe than the manual race cars do in the US..

A stock 91-98 S 600 has about 400 HP/TQ, and many of those are run on the autobahn at 200+ Km/H for hours without trans issues.... The car is also heavier than our 928... The Brabus 7.3S has 582 HP and 550+TQ, and it used a 722.3 transmission... Same with the EV12, and that car was good for 199mph with a 722.3 auto trans in a W201 E Class body.

The key is cooling in the auto box... If you want to run much power for a long period and let the trans live, use a therm switch and a cooler that will allow the fluid to stay in the comfort zone all the time....

The current Porsche 996 Turbo Tiptronic is a modified Mercedes Automatic... They live with over 400 HP/TQ and have a warranty from the factory... So does the AMG SL 55, and the Mc Merc SLR, and the AMG S/SL/CL 65..... All have a variant of the 722 transmission.... The auto's are pretty strong, no bones about it..

BTW, notice drag racers do not use manuals on their 6,000 hp sleds..... Not that it can't be done, but the auto's also shift faster than a manual...

Regards,

928ntslow

I think Jim is explaining how to keep the rpm/mph rising (quickly I might add) with no drop and not allowing the tranny to find it's equalibrium under normal driving applications. This procedure would induce the vehicle to hit hyper speed quicker than allowing it to do it itself. (Now I wish I had a 4 spd auto instead of a 3

I guess all of this confirms that I need to sell the 82 and get a GTS auto to keep the 5 spd company. Hell, Zachman did it, so can I! I am ready for a beefier daily driver.

Jeff McVicar

If you are going to use it for a daily driver and drink coffee in the morning, a five speed may get your coffee dumped on you , **** you off, and get you raging in the morning. I got an auto but if I had the choice I'd have gotten a 5 speed. Just tofeel the positive pull. But I gotta have my coffee too man.

Jim bailey - 928 International

Yes like if you decided to "road race" and use less than full throttle in a corner this allows you to select and HOLD the same gear through a corner and not have it up shift when you let up on the accelerator.