Speedometer tech

skipnrocks · Nov 18, 2015

So I have the ez tcu for my 4l80e and I have an issue. Tech support was not any help. I ordered an 8k speedo vss for my dana 300 it is the only one I could find to convert from mechanical to electric vss.

So according to tech he says all gm modules output at 4k. I couldnt find anything to support this but Im sure he knows his stuff. He said just mess with it but didnt really give me any idea as to how I could adjust to get any readings.

So here is my question. does the 4l80e actually use a 4k output, if so what can I do to get or manipulate to get the proper reading to the computer? I assume its not as easy as doubling the tire size in the computer or cutting the gear ratio in half?

pholmann · Nov 18, 2015

I would assume cutting the tire size (circumference) in half would work. Revs per mile.

skipnrocks · Nov 18, 2015

pholmann said:
I would assume cutting the tire size (circumference) in half would work. Revs per mile.

Ill give that a shot and report back

pholmann · Nov 18, 2015

Make sure u keep track of all your original parameters so you can revert back if necessary.

skipnrocks · Nov 19, 2015

I just of the tire size to maximum and reduce the gear ratio to minimum and I was able to get it to read my speed a little bit. I was able to get it up to 10 miles an hour. But I was actually driving 30 according to my GPS. Any suggestions?