ls1 to700r
Joined: Mar 2000
Posts: 43,187
Likes: 42
From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
The bellhousings will bolt together, but that doesn't mean they will simply work together.
Joined: Jan 2001
Posts: 3,188
Likes: 59
From: Conroe, TX
Car: 1987 GTA
Engine: LS1
Transmission: 4L60e
Re: ls1 to700r
My swap is on hiatus right now - but the plan is to use the 700r4. The keys that I believe you'll need to tackle are:
* Finding a flexplate/flywheel to mate the two (I got the TCI unit but haven't tried it yet. Others have used a spacer and a truck flywheel)
* TV cable hookup - this is VERY important. If it's off, you'll have a useless 700r4 in no time. I went with the TV made EZ kit and am considering a constant pressure valve body
* Torque converter lockup - the LS1 ecm won't lock your Torque converter for you. This can be accomplished in a variety of ways. I went with a TCI lockup kit that swaps the transmission over to being non-ECM controlled.
* LS1 ECM needs to be tuned to not care about the transmission (M6 tune to start with) and still read the proper speed. The M6 tune isn't calibrated for the 4000 ppm speed sensor in some of our 700r4s (87-92 firebird, 90-92 camaro?) - but I believe the auto tune is. No hard evidence there - but it's as far as I've gotten reading old threads on ls1tech and googling.
As I said, my swap isn't done. But i believe the above will allow me to use the 700r4 with the LS1. Anybody with anything better/different feel free to correct me. I'm just hoping the 700r4 lasts behind that ls1.
* Finding a flexplate/flywheel to mate the two (I got the TCI unit but haven't tried it yet. Others have used a spacer and a truck flywheel)
* TV cable hookup - this is VERY important. If it's off, you'll have a useless 700r4 in no time. I went with the TV made EZ kit and am considering a constant pressure valve body
* Torque converter lockup - the LS1 ecm won't lock your Torque converter for you. This can be accomplished in a variety of ways. I went with a TCI lockup kit that swaps the transmission over to being non-ECM controlled.
* LS1 ECM needs to be tuned to not care about the transmission (M6 tune to start with) and still read the proper speed. The M6 tune isn't calibrated for the 4000 ppm speed sensor in some of our 700r4s (87-92 firebird, 90-92 camaro?) - but I believe the auto tune is. No hard evidence there - but it's as far as I've gotten reading old threads on ls1tech and googling.
As I said, my swap isn't done. But i believe the above will allow me to use the 700r4 with the LS1. Anybody with anything better/different feel free to correct me. I'm just hoping the 700r4 lasts behind that ls1.
Junior Member
Joined: Aug 2007
Posts: 58
Likes: 0
Re: ls1 to700r
