I have a '91 CRX Si that I've just installed a mpguino in. There seemed to be some talk that one couldn't be installed because it has a mechanical speedometer. After some research it seems that there is a speed sensor that is mounted in the cluster. You can find the vss signal at B16 on the ECU harness(at least on my Si). YMMV. Rumor is the DX doesn't have one but the HF does. I had my first run with the mpguino activated this afternoon, but I had my 2 inputs switched
. 4.0mpg under heavy throttle and 0.0 mpg on overrun isn't quite right.