4l80
you can convert your 4l60 to 4l80. contact nelson performance in san antonio tx...they have what you need. not hard to do. consist of moving pins on connector and adding an extra speed sensor. plus reconfigure your your computer for 4l80
Your existing harness connector (4L60E) will plug directly into your 4L80E. You will simply need to delete one wire (Pin S-White wire) as it is for 3-2 solenoid control in your 4L60E and your 80E DOES NOT HAVE this solenoid.
Then you need to move Pin U (brown wire for TCC PWM) over to the S pin location.
That's all that is needed to modify the harness to work on the 80E. You then will need to add the ISS (turbine speed sensor, or input speed sensor) and run those wires back to the TCM. I believe-this is from memory-that it is pins 22 & 23 but I'm not 100% certain as I'm not at the shop. I have a printed page we use at the shop for reference. If you want positive confirmation, i can post back here again tomorrow for sure.
After the wiring harness changes you will then need to do a segment swap to get the 80E shift pattern into the PCM/TCM.
I would caution you to NOT DRIVE the vehicle after you get everything installed. You need to hook a scanner to the vehicle and with the drive wheels off the ground, run it through the gears multiple times from a complete stop, up to about 60MPH. You need to be watching for TCC Lock up, and you also need to run it long enough that it will set a code if something is wrong. It is VERY EASY to damage the trans on conversions like this if you go out and immediately try and drive it when it has an electrical/wiring/programming issue. Avoid those head-aches and test it every way you can before putting it on the road.
I would also caution you to check and verify that your trans dipstick is accurate. Before you add fluid to the trans, and after the trans & dipstick are installed, pull the trans pan and with the dipstick pressed all the way into the filler tube, you want the FULL mark to be parallel with the pan rail on the transmission. If you don't verify this you can easily run the trans low on fluid which can over-heat it, and cause catastrophic failure. Don't *hope* that the dipstick is correct-check it and verify for yourself.
You should have enough length available in your existing harness to get the trans connector over to the drivers side where the 80E connector is. We have only had problems with wiring harness length on the late model GTO's and on those we had to make a harness extender in order to reach over to the 80E's connector location.
If you have any additional questions, I'd love to help. My shop did over 20 of these conversions on customer cars last year. Everything from early muscle cars, to late model Silverado's, GTO's, Square Body (mid 80's) trucks, and the hardest to date-a 1980 Corvette.
Then you need to move Pin U (brown wire for TCC PWM) over to the S pin location.
That's all that is needed to modify the harness to work on the 80E. You then will need to add the ISS (turbine speed sensor, or input speed sensor) and run those wires back to the TCM. I believe-this is from memory-that it is pins 22 & 23 but I'm not 100% certain as I'm not at the shop. I have a printed page we use at the shop for reference. If you want positive confirmation, i can post back here again tomorrow for sure.
After the wiring harness changes you will then need to do a segment swap to get the 80E shift pattern into the PCM/TCM.
I would caution you to NOT DRIVE the vehicle after you get everything installed. You need to hook a scanner to the vehicle and with the drive wheels off the ground, run it through the gears multiple times from a complete stop, up to about 60MPH. You need to be watching for TCC Lock up, and you also need to run it long enough that it will set a code if something is wrong. It is VERY EASY to damage the trans on conversions like this if you go out and immediately try and drive it when it has an electrical/wiring/programming issue. Avoid those head-aches and test it every way you can before putting it on the road.
I would also caution you to check and verify that your trans dipstick is accurate. Before you add fluid to the trans, and after the trans & dipstick are installed, pull the trans pan and with the dipstick pressed all the way into the filler tube, you want the FULL mark to be parallel with the pan rail on the transmission. If you don't verify this you can easily run the trans low on fluid which can over-heat it, and cause catastrophic failure. Don't *hope* that the dipstick is correct-check it and verify for yourself.
You should have enough length available in your existing harness to get the trans connector over to the drivers side where the 80E connector is. We have only had problems with wiring harness length on the late model GTO's and on those we had to make a harness extender in order to reach over to the 80E's connector location.
If you have any additional questions, I'd love to help. My shop did over 20 of these conversions on customer cars last year. Everything from early muscle cars, to late model Silverado's, GTO's, Square Body (mid 80's) trucks, and the hardest to date-a 1980 Corvette.
