[huck369]

Originally Posted by sperry

As far as the OP's problem. It sounds like he's got the wrong speed sensor in the tranny. Since he's running the same tires before and after the tranny swap (I'm assuming) there shouldn't be a discrepency due to the 5MT.

OK, Wheel size isn't exactly what I was saying, but thought that would get the point across...
The Circumference of the tires that the tranny came with will be the difference, because all trannys DO NOT turn the same output at the speed sensor location, as the Subaru Manual Trannys are still set up to drive a cable driven speedometer which they had up untill the mid 90's, and there is a gearset inside the tranny that is matched to the final drive ratio and the tire circumference Do yes, he's running the same tires before and after his swap, but the TRANNY is NOT running the same tires it was set up for, the Speed sensor just converts the rotational output of the transmission into a digital signal so no matter WHAT speed sensor you install it will not read correctly, there are aftermarket setups that adjust the digital signal between the speed sensor and the speedometer, but without that you either need to find lower profile tires to try to match the transmissions original tire size (and if it were a tranny set up for 13's you'd probably have to run just the 16" rim with a strip of rubber around it) or you would have to open up the transmission and install a different speedometer gear drive set.

A bit of a plus is the SVX (as most cars) stock the speedometer is off to the slow side, saying you are going faster than you really are...so some tranny swaps actually work out to a more accurate reading, some make it worse,,,