If you talk about the 996 Porsche, the tranny ECU is definitely
connected to the engine ECU!
It gets rpm, calculated torque, speed, engine temp etc. It also sends
info to the engine: real torque, shifting point requests (to lower
engine torque during the shift)
The 993 4-speed automatic tranny is also connected to the ECU, at least
in Audis. And these are similar to the Porsches.

Raimund

John Reddick schrieb:

>I am thinking of going the 911 Tiptronic route on my 91 van with a JDM
>2.0 turbo Subaru motor I am going to put in.  The 911 auto transmissions
>are not difficult to find, and at 1500-1800 dollars are a little cheaper
>than a beefed up automatic van transaxle.  They also have limited slip and
>much taller gearing.
>    I have talked to a few shops that part out Porsches and know a bit
>about them.  They said the separate ECU for the transmission does is not
>connected electrically to the engine ECU or engine.  I am going to confirm
>this before I buy one but right now I think it is pretty doable.
>    I will let this list know the further along I get.
>
>    John
>    87 Westy SVX
>    91 GL (just starting 2.0 Subaru turbo conversion)
>
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