I just switched from 323 gears to 342 in my 93Z. I did a search to try and find the right gear combo but found nothing. With out having to go through a lot of work could anyone tell me what the right gear or gears would be to get my speedo working correct. The car is completly stock a4 with stock size tires. Thanks for any help offered.

 

As best that I can tell I am 10mph off. 55 is 45. Thats buy following traffic. still wondering if anyone can help me with this. thanks

 

Changing from 3.23's to 3.42's will not cause that large a speedo error. It's only a 5% change. At an actual 55 mph, your speedo should only read 52 mph. If yours is 10 mph off, there are other problems.

To get that much difference, you would have had to be going from 2.73 to 3.42.

 

My 93 Formula had an optimistic speedometer by about 5mph with older GS-C tires. I think the 93's were a little less accurate due to the gear drive.

Sorry I don't know the right gear combo. You may be better off asking for help in a 3rd gen board, cuz 93's are the only guys with speedo gears.

 

Thanks for the info guys. At least now I have a place to start.

 

what about the rest of us? how do we get it correct?

 

Have to change the programming of the PCM.