84 fiero
billy 84
03-03-2009, 06:35 PM
84 fiero 4 cyl. and I install a 85 2.8 v6 with 85 engine wiring and ecm car will start have no power how can I adapt into 4cly wiring to car run what will work HELP THANK YOU
Old Lar
03-04-2009, 03:48 PM
http://www.geocities.com/MotorCity/Garage/5007/fiero_osg/mod.engine-swap.html
From the how to thread: What you will need to do is to get the wiring diagrams for the 84 Fiero and the wiring diagrams for the V6 engine then rewire the car. The 84 did not have a V6 in its plan when built. This can be a time consuming process matching or adding wires to make the swap. Some just suggest sell the 84 and buy a V6 Fiero.
The swaps have been done, but usually by people with money or skills in car wiring. Not an easy task.
From the how to thread: What you will need to do is to get the wiring diagrams for the 84 Fiero and the wiring diagrams for the V6 engine then rewire the car. The 84 did not have a V6 in its plan when built. This can be a time consuming process matching or adding wires to make the swap. Some just suggest sell the 84 and buy a V6 Fiero.
The swaps have been done, but usually by people with money or skills in car wiring. Not an easy task.
billy 84
03-05-2009, 11:37 AM
do you have pics.or views of the 85 c-500 treminal block so I can change pins
billy 84
03-24-2009, 09:15 PM
I have a 84 fiero with a 3.4 3 speed auto and trans is junk will a 4t60 work in my fiero need help thank you
Ragtop_Renegade
03-27-2009, 02:10 AM
A 4t60 fits the engine. As far as bolting into the fiero, there are some complications.
Be aware that there are as many as 3 or 4 different 4t60 cases, each having different mounting bosses designed for different body styles. Be certain to get a 4t60 with a mount plate location in the same place as the th125, or you will need to do some cutting and welding to get a suitable mount.
Th125 axles should have the same spline count as a 4t60, but you should verify this.
I've personally never looked.
There is some complexity with using the 3 speed shifter along with a 4 speed transmission. While it should work ok if the cable is properly set, be aware that you will have a shift range of 2-D-OD, manual override first gear will be unavailable unless you find a suitable 4 speed shifter that fits the fiero console. This may take some creative modification and/or fabrication.
You will need an electronic speedometer pickup. This shouldn't be a difficult find, as most (if not all) 4t60 units used a speed sensor in lieu of a cable. The older th440-t4 that predates the 4t60 used either, depending on the model. Results may vary, but you may need to have the speedometer re-calibrated or use a self calibrating electronic speedometer such as those offered by AutoMeter and Stewart-Warner.
4t60-e transaxles should be avoided. While identical in dimensions to a 4t60, they do not function without the correct PCM and wiring harness. Even if you were to make the conversion, each PCM is customized to the model it was installed in. Chances are your shift points will be all wrong, and without custom programming you will have suffered a lot of work for a big disappointment.
Be aware that there are as many as 3 or 4 different 4t60 cases, each having different mounting bosses designed for different body styles. Be certain to get a 4t60 with a mount plate location in the same place as the th125, or you will need to do some cutting and welding to get a suitable mount.
Th125 axles should have the same spline count as a 4t60, but you should verify this.
I've personally never looked.
There is some complexity with using the 3 speed shifter along with a 4 speed transmission. While it should work ok if the cable is properly set, be aware that you will have a shift range of 2-D-OD, manual override first gear will be unavailable unless you find a suitable 4 speed shifter that fits the fiero console. This may take some creative modification and/or fabrication.
You will need an electronic speedometer pickup. This shouldn't be a difficult find, as most (if not all) 4t60 units used a speed sensor in lieu of a cable. The older th440-t4 that predates the 4t60 used either, depending on the model. Results may vary, but you may need to have the speedometer re-calibrated or use a self calibrating electronic speedometer such as those offered by AutoMeter and Stewart-Warner.
4t60-e transaxles should be avoided. While identical in dimensions to a 4t60, they do not function without the correct PCM and wiring harness. Even if you were to make the conversion, each PCM is customized to the model it was installed in. Chances are your shift points will be all wrong, and without custom programming you will have suffered a lot of work for a big disappointment.
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