Just wondering why??
The first one I had was a stock one from the boneyard and it lasted a couple of years behind a stock 350. I expected it to go bad, but, even though I made some mods to it I was never happy with the way it shifted.
The one I have now is a Bowtie Overdrives level 3 that's suposed to handle a BBC like mine with no problem. I installed it in March of 03 with my current 454. I performed all the pressure checks and followed BTOs instructions to the letter and was blessed with thier one year warranty. The odometer was reading about 11,000 miles then and it's showing 29,000 now. The tranny was OK but never shifted as firmly into 3rd as I liked. I spent many hours adjusting and readjusting the tv cable trying to find a "sweet spot" between an acceptable street shift point/firmness and a wide open TH 400 turbo kind of shift into 3rd at the track. Last year I made a few runs down the local track and noticed the shift into 3rd had a momentary delay(like kicking in a clutch)but it shifted ok but didn't slip. A month ago after a head upgrade to the 454 I went for a shake down run and that's when the slipping in 3rd started. I went down the track a couple of times while at CB08 and found the shift delay/slipping to be getting worse.
So to make a long story short I'm not happy with a transmission that simply can not perform as good as an old TH350 or TH400. I've beat on the old 350/400s as hard as you can and rarely had a problem.
Don't get me wrong, I love an overdrive and will have one in some form, but the 700r just doesn't cut it with me anymore.
I have seen that TCI now has a valve body that maintains a steady pressure,
But I don't know if that's the answer to the problem or not. It still requires a tv cable to regulate part throttle shifts.
I guess I should call BTO and see what they say about the valve body. I hesitate though because they seem to have an attitude, like, they designed the wheel, and I'm not going to listen to much of that.
The bottom line, if I can convert to a 4l80e without going broke, I'm going to give one a try.