Shift Points of an AT ECU

MichaS14a · Post by **MichaS14a** » Sat Dec 06, 2008 9:16 pm

Hello!

I friend of me has an AT (Automatic Transmition) S14 with SR20DET. He has changed the camshaft as the original ones are broken (due to the oil lines to the camshafts are jammed).

Know he asked me if the Shiftpoints can be modified with NIStune as the characteristics has be changed with the new camshafts.

I have loaded an original S14-ROM but I am not able to locate a map where I can change the shiftpoints.

Does anyone have suggestions to influence the shiftpoints?

Regards
Michael

kenbam · Post by **kenbam** » Sun Dec 07, 2008 8:10 am

im more into the skylines and z32's but im guessing the s14 will also have its own ecu for the transmission. Totally separate from the ecu that nistune does. Nistune will not be able to change shift points.

Legionnaire · Post by **Legionnaire** » Sun Dec 07, 2008 8:22 am

AFAIK, of ecu's that can be "nistuned", only skyline r34 has ECM and TCM in one control device, but being physically connected (mounted on a same motherboard) does not nesessarily mean that they share same memory and use same data structures. So the answer is no

Matt · Post by **Matt** » Sun Dec 07, 2008 10:58 pm

automatic trans in most ECUs is a separate computer and altough sometimes you can communicate to them using the same consult port, they are a different device still

they have no remappable hardware in them so cant be easily changed. i attempted reverse engineering of my R31 trans controller just for interest sake and couldnt make sense of it (I wanted to change shift points also)

not much we can do about it unfortunately.

MichaS14a · Post by **MichaS14a** » Mon Dec 08, 2008 1:20 am

Thank you very much for the answers!

So I know that I didn't made a mistake and it is for now impossible to change the shiftpoints.

Legionnaire · Post by **Legionnaire** » Mon Dec 08, 2008 9:38 pm

Well, that does not mean that you have no options. You can try some kind of standalone TCU - like PCS one: http://www.powertraincontrolsolutions.c ... ent-4.html

They have RE4 R01A listed, which is what you have in there if i'm not mistaken. With some decent valvebody, torque converter and reinforced clutchpacks and band you will get excellent tranny for your car.

Eric · Post by **Eric** » Mon Dec 08, 2008 10:20 pm

you could contact Maciej Nowakowski @ ESS racing
He has developped a standalone TCU for the 300ZX/Z32 that has several programmable variables (shiftpoints, linepressure, etc.) and it can also be set into a "manual" mode, so you can shift manually using paddle shifters

http://www.es-ab.se/ess%2Dracing/

maybe he's able to help you.

MichaS14a · Post by **MichaS14a** » Tue Dec 09, 2008 12:31 pm

Thank you very much for this informations!!!!

I will tell my friend from this solution and ill be shure if there is a way to make it run on a S14 he will be very happy!

Shifiting like a F1 car is awesome! I have never thought that there is a way to shift like this for a Nissan with automatic transmition.