Huge push on the tuning in for this yesterday. I finally managed to dial in the 3-4 shift.
It is a clutch to clutch shift which means that it has to be timed properly or you can get bind or a flare up like from being essentially in neutral for a short time.
I was working on some valve body modifications and realized something in my tune that would help a great deal. The problem has always been that as you try and tune out the flare up that the transmission would bounce back into 3rd uncontrolled. Pressures in the valve body and valves not in the correct position. I realized why that happens on Friday and was able to make a fairly simple change in the tuning to use as a test and completely eliminated this problem.
Then to the flare up. I have a local customer with a '73 CUDA/Challenger with 5.7hemi and a nag1 or 722.6. Completely stock transmission. I changed his calibration and was not able to get rid of the flare but then after a couple of tries on the valve body was able to completely nail the 3-4 shift at wot.
Simply opening up the hole for the k3 clutch on the intermediate plate were it bolts to the transmission allowing the clutch to fill faster at lower pressure did the trick. I have some more work to do on how big the hole should be. We ran out of time yesterday. I would like to try a little bigger. Although it does not seem to need it.
Cannot wait to try this on my coupe. This was the last big tuning hurdle I had. The system is just really good now.