Please help, ECU confussion

madrid'sFC3 · 10-11-2012, 07:50 AM

hey guys, i had my 91 FC converted to a 5speed a little while back, and it still has the same ecu before it was swapped over. i recently just bought a GTU cluster on ebay and i was wondering which ecu matchs up to the gtu? will my stock automatic ecu (which ever that might be) let me rev up to 9k or will it stop at 8? pleases help!!

Raksj04 · 10-11-2012, 08:44 AM

I wouldn't rev the Car past 8k anyway, not untill you buid the motor up. If you are going to replace the Ecu I would go with a rTek, website ( www.pocketlogger.com ). You could send your Ecu and you can have it upgraded, or find one that alright has it done.

N350 - 89 NA California
N351 - 89 NA
N352 - 89 Vert California
N353 - 89 Vert
N370 - 89 Turbo

those are all S5 (89-92) ecus. Once you have a rTek you can tune your car with a Palm OS PDA, they have a list on the website above. I haven't found any difference between a manual and Auto Ecu, however I maybe wrong.

however is the car a Coupe or a Vert?

vrracing · 10-11-2012, 02:47 PM

The S5 automatics have a separate computer for the tranny. When you do the conversion you just unplug it.

The ECU is unaware of whether the tranny is auto or manual. It just takes equivalent inputs (clutch safety switch, neutral safety switch, etc) from either.

The gauge cluster only handles display. It won't limit the engine RPMs in any way.

madrid'sFC3 · 10-12-2012, 04:36 PM

Oh ok thanks guys! And my FC is a coupe. I will definitely look into the rTek website. I was planning on doing a mild street port with a bigger injectors. Nothing too big tho. But thank you guys!!

10-11-2012, 07:50 AM	#1
madrid'sFC3 The Newbie Join Date: Jun 2012 Location: Rome, Ga. Posts: 11 Rep Power: 0	Please help, ECU confussion hey guys, i had my 91 FC converted to a 5speed a little while back, and it still has the same ecu before it was swapped over. i recently just bought a GTU cluster on ebay and i was wondering which ecu matchs up to the gtu? will my stock automatic ecu (which ever that might be) let me rev up to 9k or will it stop at 8? pleases help!!

10-11-2012, 02:47 PM	#3
vrracing Rotating Assembly Join Date: Oct 2008 Location: TX Posts: 102 Rep Power: 18	The S5 automatics have a separate computer for the tranny. When you do the conversion you just unplug it. The ECU is unaware of whether the tranny is auto or manual. It just takes equivalent inputs (clutch safety switch, neutral safety switch, etc) from either. The gauge cluster only handles display. It won't limit the engine RPMs in any way. __________________ 90 S5 Vert. JDM Tii with BNR Stage1 turbo. Pineapple Racing street port. Bonez cat-forward. Corksport cat-back with Vibrant UltraQuiet resonator. RTek 2 wZeitronix w/b. HKS EBC. Vis CF Tii hood. 3000GT wing. Ground Control coilover kit with KYB AGX shocks. Red and Black leather RX8 seats. Corksport Odura lip & bumper caps, OEM Tii skirts

10-11-2012, 08:44 AM	#2
Raksj04 I have Ultra power in me. Join Date: Sep 2011 Posts: 457 Rep Power: 15	I wouldn't rev the Car past 8k anyway, not untill you buid the motor up. If you are going to replace the Ecu I would go with a rTek, website ( www.pocketlogger.com ). You could send your Ecu and you can have it upgraded, or find one that alright has it done. N350 - 89 NA California N351 - 89 NA N352 - 89 Vert California N353 - 89 Vert N370 - 89 Turbo those are all S5 (89-92) ecus. Once you have a rTek you can tune your car with a Palm OS PDA, they have a list on the website above. I haven't found any difference between a manual and Auto Ecu, however I maybe wrong. however is the car a Coupe or a Vert?

10-12-2012, 04:36 PM	#4
madrid'sFC3 The Newbie Join Date: Jun 2012 Location: Rome, Ga. Posts: 11 Rep Power: 0	Oh ok thanks guys! And my FC is a coupe. I will definitely look into the rTek website. I was planning on doing a mild street port with a bigger injectors. Nothing too big tho. But thank you guys!!