ok here goes.i will be searching the net for the answer and post it if i find it before it gets posted here.i have a 94z28. i pulled the 4l60e and replaced it with a 4l60/700r4 from a 91 firebird with 305 tbi.i plugged my vss wire up.it reads like .1 miles to every 2 miles i go.is the problem with my vss , my pcm , or my speedo?seems the signal is getting thru , just wrong?the speedo even moves and comes up to like 5mph when im doing like 70mph

 

The answer is in the number of pulses per mile ( PPM ) generated versus the number expected. However, to have made this swap, you would have had to get the 4L60E tune replaced by a T56 tune, so the computer wouldn't try to control an electronic VB that the 700R-4 doesn't have, but the 4L60E did. Otherwise, your SES light will never go out, and you'll be in limp-home mode forever.
Whomever swapped tunes for you should have reset the PPM to match the older sender.
However, you may be able to remedy this just by swapping in the sender from the '94 4L60E, IF your 700R-4 uses a steel longitudinal-tooth "gear" on the output shaft, rather than a plastic speedomer gear.
Otherwise, the plastic gear can be removed, then you can press on a new steel using a length of pipe.
This still requires the T56 tune.

 

Problem is, you went from a sender that puts out something like 40,000 pulses per mile, to one that puts out 2000.

Easiest thing to do is just put the reluctor, extension housing, and VSS from the 4L60E, on the 700.

 

yes thats what i'm thinking too.

 

i should have posted more info.i have swapped out the lt-1 as well.i now have a carbed 350 in it.so the ses light is eventually gonna burn out.thanks guys for your replies.