Hello to the forum, and with my first post I start out asking for help. I have a 2001 Ford Crown Victoria, base model, that I pretty much converted to the "police package"
I installed a full suspension with springs, anti-sway bars, shocks, 11.25" torque converter (factory was 12",) 3.55 rear gears with traction lock (factory was 2.73,) dual exhaust, aluminum metal matrix drive shaft, extended tail housing, black speedometer gear (for accurate speed readings with 3.55 rear gear and 8-tooth output shaft) and a (used) BCA valve body with both lower accumulator springs removed. I did not swap out the short tail shaft for the long tail shaft. I only swapped the tail housing for the longer version.
I also use a P71 engine computer from the same year so that the programming is correct for the torque converter and gear (well, almost - 2001 P71 factory gearing was 3.27.)
Anyway, I have ran this setup for over 4 years now.
The shifts are not harsh at light throttle, but they will chirp the tires at full throttle, and under moderate throttle when it is wet.
I am not a track runner, or a racer, or someone who generally drives fast. But knowing that I could not safely operate the car in a more spirited level of acceleration when it is wet out makes me somewhat uncomfortable.
Even last year, under really light acceleration, I felt the rear end just *barely* slide on the 1-2 shift when there was a bit of black ice on the road.
I assume that my best course of action would be to re-install both of the lower springs for the 1-2 and 2-3 accumulator.
I bought the used BCA valve body from a guy who wrecked his car. I had an experienced transmission tech open up the valve body and take a look to make sure it was OK before I installed it. He said the holes were drilled differently than the J-Mod specification, but I do not remember what was different exactly. It is also possible that BCA Automotive has some other changes.
The reason I wanted to do the J-Mod or BCA valve body was that my transmission still shifted different than a P71, so I wanted to firm it up somewhat without being harsh. Yeah, the quick tire chirp shifts were cool when I was 21 years old, but I don't think they are that cool anymore. I drive very conservatively. I do like a clean, quick shift, but I would like it to shift without harshness that will cause tire chirp or dangerous fishtailing when it is wet (which is exacerbated by the traction lock!)
There must be something different about the base model valve body, if it shifts more drawn out than the P71 transmission. Besides that, the transmissions are identical, with the exception of the tail shaft.
Anyway, I am running the BCA valve body with my lower accumulator springs removed. I still have the factory original upper accumulator spring installed for the 1-2 accumulator.
Any suggestions as to how to remove the harshness of the (especially) 1-2 and 2-3 shifts? Should I purchase some other accumulator springs that are different than my factory original springs?
PS - I am not exactly sure what this BCA valve body was built for, but I know the guy had a supercharger in his 2v 4.6 Crown Victoria. So perhaps it was built for a more aggressive shift to begin with.
Although my car doesn't shift terribly hard, it will break traction, especially in the wet. And this is what makes me uncomfortable.
A friend of mine had a B&M shift kit in his 4R75E and it shifted perfectly. It was a quick firm shift but it wasn't jarring or hard. It's hard to describe...
You can see a a video that I filmed of how my car shifts last November here:
That was filmed with a slightly dirty MAF sensor so likely now the car spools up a bit quicker than in the video.