az_eric

So heres the low down. I have a 75 k5 blazer. I bought and install a 350 tbi motor computer harness out of a 95 g30 van. It came equipped with a 4l80e but I was going to use my t350 so I cut all the unused trans wire out. Well several months later I changed plans and now want the 4l80 in it. I still had access to the van so I went back and grabbed the vssb cruise control stuff and what ever else I thought I might need.
So I find a 4x4 trans out of a 94 suburban and start wiring everything up. Got it up and running and now I'm having issues. It won't shift into second unless the speed is relatively higher and won't shift until I let out the throttle. Same with third gear. But with third gear whem I reapply throttle it will down shift back into second. I hooked a scanner to it to see whats going on. Not getting any codes but its showing shift fault 1&2. Also noticed the speed its showing on the scanner is about half of what I'm really going. As far as I know everything is wired right. Im at a loss here and hope u guys can help.

az_eric

Let me ask another question. I'm thinking that not having the vssb calibrated to my gears and tires might be causing this issue. Is it possible that it could be whats causing my speed reading on the computer to be so far off?