The Mustang Forum for Track & Racing Enthusiasts

Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.

  • Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!

Gear change will speedo show correct speed?

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

209
79
ny
Question if I change rear gear from 3.73 to 4.10 will speedometer read right speed?

I know older stangs you change cable gear. I'm pretty sure that cable doesn't exist with 13 boss 302. Or is there a computer reset?
Tx chris
 
No it won't read the correct speed. You have the change the rear gear ratio in the computer using the interface of your choice - SCT, Forscan, HP Tuners, Ford Dealer, etc. Same deal if you change tire height from OEM and end up having different Revolutions/Mile.
 
No it won't read the correct speed. You have the change the rear gear ratio in the computer using the interface of your choice - SCT, Forscan, HP Tuners, Ford Dealer, etc. Same deal if you change tire height from OEM and end up having different Revolutions/Mile.
Something like this. This is for a S550 but good chance something simple like this may be the same across generations.
1728855344249.png
 

TMO Supporting Vendors

Latest posts

Buy TMO Apparel

Buy TMO Apparel
Top