go to http://www.tciauto.com/Products/Tech...eedo_gears.asp, about half way down the page, just plug and play. The only problem, you don't know if your C4 drive gear is 7 or 8 tooth. An option is to take your existing speedo gear count, probably 16. Don't know what tire you're running, but you either need a 21-22, or a 24-25tooth speedo gear depending on the tranny drive gear. There is no determining your drive gear unless pull the tale section of the tranny. You might be able to count with a good mirror, agood eye-ball, and a flash light.

 

I took the gear out and it isa Type A, Green, so I see that is a 17 tooth gear, my options from NPD are below, I could not see the gear inside tranny to see if 7 or 8 teeth. I guess it is trial and error at this point.
Should I order a 19 and a 21, or should I stay close. 18 and 20?

Type 3 Blue, 16 tooth, RH rotation........17271-2 7.11

Type 3 Clear or green, 17 tooth, RH......17271-4 7.60

Type 3 Tan, 18 tooth, RH.......................17271-5 6.74

Type 3 Tan, 19 tooth, RH.......................17271-6 7.60

Type 3 Orange, 20 tooth, RH.................17271-7 8.02

Type 3 Purple, 21 tooth, RH..................17271-8 7.11

 

I believe the gear inside the transmission is fixed, not changable. The difference in gears and tire size are the deciding factors. So far, your tire size, diameter, needs to be included. All taken into consideration, a 19 tooth may be a good starting point. I don't remember where or when or how much of a certain adult beverage was consumed, but a one tooth change is equal to five mile per hour.
Jim