1985-1998 [Subscribe to Daily Digest] |
There is a definite difference between a T-25 and a TD04 ECU. They are NOT the same.
The ECU controls when to open the wastegate via the BPC (thing sitting on top of the radiator with 3 hoses coming out of it). The TD04 huffs out much more air than a T25, and so, can sustain higher pressures. The ECU will keep the wastegate closed longer on a TD04. This is why stock max psi on a T25 is around 12 - 14, and in a TD04 it's 16 - 18.
An auto vs. a 5-spd ECU is just a matter of internal software differences. With a T25 ECU, the ECU will limit the amount of torque being produced and transferred to the auto transmission (supposedly to safeguard against shortening the life of the tranny). That is where this Fuse 9/Pin 14 trick comes in. When Pin 14 is energized (by shifting the auto selector to a forward gear), it tells the ECU that this car has an auto and torque output must be limited. If that pin is not energized, as is the case in a 5-spd or if you've incorporated this trick, then the ECU will allow the engine to produce more torque. Don't just pull the fuse and drive like that: this fuse controls the sunroof, rear windows, cig lighter, idle, and brake boost. Best to install a toggle switch in-line to Pin 14 (orange wire to ECU).
So, the bottom line here is how much more power you want: a TD04 with a T25 ECU will make more power than a T25 setup will, but will not make as much power as a TD04 with a TD04 ECU. A T25 or a TD04 (no matter what ECU)without the Fuse 9/Pin 14 trick will not make as much torque as is generated in a 5-spd.
Joe
'98 115K
'93 900TC 156K
posted by 167.211.1...
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