86 automatic transmission better than the 87?
 

Which automatic transmission is better? An 87 4-speed automatic or the 85'/86 4-speed automatic? I hear the 85 86 has the first gear start. Will it bolt directly to an 87 s4? or do you have to change the torque tube also?

The S3 automatic has a smaller (higher stall speed) torque converter. Four speed auto torque tube is the same 83-95.

Note '85-'86 and '87-'88 autos have a 2.20 ratio final drive vs. 2.54 '89-'95.


I make a gizmo for First Gear Start. Starting off in first most of the time makes my '89 feel like it has lost 500 lbs.

Talk about that gizmo please, Ken?
If a person actually has their hands on an S3 transmission, they’ll need the complete kickdown/Bowden cable and shift cable for the S3.
Yes, the trans and TT should bolt right in and there will be more empty space up between front cover and tunnel afterwards.
it’s a lot of work of course. Think about preemptive maintenance before you install it; front pump/piston seals, TT bearings just to start. A thirty seven year old transmission has lots of brittle seals. Or just get a rebuilt from Greg if he has one.
​​… and BTY you’ll notice that higher stall speed with the 86.5. But if Greg chimes in he can advise if it’s actually a great idea for your ‘87

Is that "gizmo" the kick down relay mod with the thumb button activation? If so, I have the same on my 84 and it gives you more control over the automatic, not just when starting off from a stop but also while driving, allowing you to command a downshift at any throttle pedal amount and hold lower gears in corners.

PKSportmode - 87-95 Auto Sport Mode with First Gear Start
 

I thing "gismo" means this by PorKen?
https://cimg1.ibsrv.net/gimg/rennlis...ad2268cd75.jpg
PKSportmode - 87-95 Auto Sport Mode with First Gear Start

Why did Porsche change from 1st gear starts in 1986 to 2nd gear starts in 1987 (with the option of kicking down into 1st gear by flooring the throttle, if needed?

Porsche just stupid?
Porsche wanted the car to be slower?
Better fuel economy by requiring more throttle opening to accelerate in 2nd gear, the same as it would in 1st gear?

Anyone have any clue?

Because after rebuilding dozens and dozens of these transmissions that were driven stock with 2nd gear starts, versus rebuilding dozens that were modified to start in 1st gear, I do know, for certain!

https://cimg2.ibsrv.net/gimg/rennlis...0964153df7.jpg

https://cimg3.ibsrv.net/gimg/rennlis...16b98deeb0.jpg

I have seen the pain this causes..no lies detected. It is slowly breaking a thing..well, three things.

Will do tell what is it breaking and how bad?

Maybe smoother starts or less wheelspin risk when traction is low. I know some cars do a 2nd gear start when in winter mode and the Cayenne does a 2nd gear start in normal mode and a first gear start in sport mode, but that may be related to building turbo boost, and the 928 isn't turbo charged

+1
Our 986 starts in 2nd unless you put it in manual mode and shift into 1st. Even the most anemic of the water-buffalo flat 6's that's in our car has plenty of torque to get moving in a hurry in 2nd gear from all but a dead start.

Was this really a Porsche thing or a Mercedes thing? At least the Mercedes had a 1st gear selector.
https://mbworld.org/forums/e-class-w...cond-gear.html

My 87 drops into 1st below some speed (3-4mph) every time if I have my gear selector in 2nd.

A slightly higher stall torque converter with the automatic trans from an 89..... if this combo had been introduced in 1987 (or even 1985) we most likely wouldn't have threads like this.

Greg showed me a box full of the "distressed" part(s)..I'll leave the knowledge to him, unless he want to share it.

I dunno man. Your guy has a documented tendency of "exaggeration". Eh, pulling stuff out of his... hat. :roflmao:

He apparently connects planetary wear with "kickdown switches".
https://rennlist.com/forums/928-foru...irst-gear.html

Folks who use a kickdown switch also drive their cars harder and have more high rpm, high torque, shifts?

So, not a problem with first gear per se, but heavy throttle and high rpms.

FWIW, my gizmo works with minimal throttle and becomes stock with more throttle as the spring compresses. It essentially automates the >26° takeoff change to first gear but at low load. Depending on how tight the cable is adjusted, shifts are a little higher in rpm but again, at low load.

Yeah,
Never mind.
All is good.
1st gear starts in S4's a great idea!
Just ask PorKen for what he has seen, taking automatics apart and studying the damages, when he rebuilds them.
And ignore that AMG made some special heavy duty parts, so that they could do 1st gear starts.

Porsche was obviously just being stupid, again.