928cs

I would like to share with you the various kinds of sport seats produced by Porsche for the 928.
These are production seats, so you could found some curiosities into prototypes...

Of course, feel free to correct me or ask if you have any question.

The pictures are in the same order as the text below.

1981 to 1984 model-year, M409
The M409 equipment code implies that both front seats are sport seats, and the covers of the rear seats are also different.
The seats are fully manual, and could not be ordered with heating system.
The covers are identical to 911/944 seats and not the usual 928 ones.

1985 to 1995 model-year, M383/M387
M383 is the left sport seat with electrical height adjustment.
M387 is the right sport seat with elctrical height adjustment.
It was possible to order one side only, or both. This was a free option, and the rear seats were not modified.
It was possible to order the optional heating system, for one side, or both. M139 for the heating of the left seat, M340 for the right seat.
Not compliant with a seat and side mirrors memory system.
The rear seats are identical to the regular ones.

1988/1989 CS only, the combination sport seats M377/M378
The codes were only used for the 1989 CS, but the 1988 had the same seats.
M377 is the left seat, M378 is for the right seat.
They are fully manual, and could not be ordered with heating system.
Of course, they are not compliant with a seat and side mirrors memory system.
In fact, they are made a basic non electrical lower part from a 944 or 911, with an upper part from the regulat sport seat. This explains the name "combination". The covers are regular 928 ones.
Not all CS were ordered with them (at least one was ordered with regular electric seats, and one with M383/387 sport seats).
The rear seats are identical to the regular ones.

I hope that this is clear.

Additional information:
The supple leather option could not be ordered with sport seats.
If sport seats are covered of leather, the central inserts are covered with perforated leather, as are the rear seats.

Michael Benno

Thanks for the super useful information. Did M377 and M378 have the sport bolsters only on the back and the bottoms were standard shallow bolsters? Or were they the bigger bolsters like those found on 944 Sport seats with electrical vertical adjust?


I am having some sport seats made from 944 seats for my 1988 S4 5spd LSD.

The right left seat is fully manual now and will be converted to a sport back and bottom as well as have heat added. So I figure that would be like adding option codes:
- M378 "combination seat, right, adjustable"
- M340 "Seat Heating System, Right Seat"

The left seat has electric vertical adjustment and will be converted to sport back and bottom will have heat and lumbar control (bulb). So that will be like adding option codes:
- M383 "Sport Seat Left, Electrical Vertically Adjustable"
- M139 "Seat Heating System, Left Seat"
-M586 "Lumbar support - Left Seat"

928cs

Yes, M377/M378 CS seats have shallow bolsters bottom. Only the upper part is identical to regular sport seats with electrical height adjustment.

By the way, production sport seats were not compliant with lumbar support.

Rob Edwards

Great info Samuel, thanks for sharing it!

Tom. M

Did they add the adj seat heating (small wheel in center of switch) in 89? My 89 sport seats have the adj heat..and the sport seat in my old 87 just had the on/off switch.

merchauser

I cannot find seats or seat parts in the PET for 87-91 cars???

are the front seat backs interchangeable?

do the seats interchange with any other models like 911??

928Myles

Merchauser,
from my observations of fitting lumbar support to my seats the seat backs will fit both sides. Not sure about interchangability with other models.

Myles

Bigfoot928

I added the lumbar to my comfort drivers seat, and also added the sport seats bars and foam.

Red Flash

Sam, thanks for this information!

Does anybody have a picture of heat seater control? Thanks in advance to post a picture, if you can!!

Speedtoys

Good info.

Ill share photos of a set of normal S4 seats that I am having converted to sport seats -and- widened 2" from Rob Budd soon. Hopefully in 2-3wks.

Tom. M

Here's the adj. one on my 89GT ..

Red Flash

Hi Tom! Thanks for that picture! I am just now coming back to this topic and somehow missed your post over a year ago...

Can you also post a picture of those seats and the option codes? It looks like those could be the type of seats originally delivered on one of my GTs.

My car was equipped with:
M383 Sport Seat Left, electrically vertically adjustable
M139 Heat seating left
M387 Sport Seat Right, electrically vertically adjustable
M340 Heat seating right

Unfortunately, I am trying to put the car back in stock condition, but don't know really which seat I need... I guess based on Samuel's pictures in the middle type of black ones above. Right now the car has new looking 8-way electrically adjustable comfort seats.

Tom. M

Looks like those are the same codes as mine. I've attached a pic of the option codes from my GT..And the second pic Samuel posted are exactly like mine.

Red Flash

Tom/Samuel --> Merci beaucoup! That is pretty much an open and shut case for what I am looking now!

slownrusty

@Michael Benno - Can you post some more details of the 944 sport seats that you are making for your 928?

Thanks