rhino
Newbie
- Make
- Chevrolet
- Model
- Caprice
- Year
- 1994
- Miles
- 1500
- Engine
- LT1
Newly rebuilt 1994 4l60e that works perfectly except for this one problem.
My tune has the 3rd/OD shift point at 46mph, converter has already locked at this point. This shift point is assuming very low load acceleration. The problem comes when slowing from speeds above 46mph, as in just taking your foot off the gas. When the vehicle speed reaches 46mph, the trans kicks out of OD and free wheels as long as you are decelerating. The engine is at idle rpm (ie 750) now. If, say, at 38mph you want to begin accelerating again, you will need to increase the rpm to match the speed/gear combination in effect right now. Example: at 38mph, trans would be in 3rd/locked, so engine would need to come up to 1800rpm before 3rd/locked would re-engage and allow you to continue accelerating. Trans would shift to OD at 46mph as normal and as your speed increased, you would have compression braking if you decelerated. Until you hit 46mph again, and then OD would disconnect and you would free wheel all the way to a stop or until you accelerated again. I don't think this is a design feature.
Any comments or suggestions would be appreciated.
Dave
P.S. The vehicle info given is for the engine, trans, PCM, harness. (donor car).
My tune has the 3rd/OD shift point at 46mph, converter has already locked at this point. This shift point is assuming very low load acceleration. The problem comes when slowing from speeds above 46mph, as in just taking your foot off the gas. When the vehicle speed reaches 46mph, the trans kicks out of OD and free wheels as long as you are decelerating. The engine is at idle rpm (ie 750) now. If, say, at 38mph you want to begin accelerating again, you will need to increase the rpm to match the speed/gear combination in effect right now. Example: at 38mph, trans would be in 3rd/locked, so engine would need to come up to 1800rpm before 3rd/locked would re-engage and allow you to continue accelerating. Trans would shift to OD at 46mph as normal and as your speed increased, you would have compression braking if you decelerated. Until you hit 46mph again, and then OD would disconnect and you would free wheel all the way to a stop or until you accelerated again. I don't think this is a design feature.
Any comments or suggestions would be appreciated.
Dave
P.S. The vehicle info given is for the engine, trans, PCM, harness. (donor car).