The Stovebolt Site Forums The Shop Area Driveline Please pay attention

I constantly read inquiries about speedometer problems when doing T5, other overdrives, transmission, rear end, and tire size changes. This can be remedied SO EASILY with a gps speedometer where whatever change is made makes no difference to the speedos accuracy. I keep waiting for a supplier to make an attractive bezel insert to complete the swap. No gears, no cables, just a dead accurate speedometer for under a hundred bucks. Ones who live where there are tunnels say they work there also.

GPS speedo app on phone make it easy to dial in a mechanical speedo. Drive 50 mph & see where the speedometer reads. difference either = or - , times 2 will give the % either plus or minus. With that info either do the math on drive / driven gear or get a speedo adapter. Some of us have several different ratios adapter rat holed, post what you need and might get a free one!

Yup thats how I set up mine on my 3/4 ton with the BW OD. I figured out which stewart warner ratio adapter would work and found it on ebay for a decent price. Ended up with a .8974 conversion. It runs pretty much dead on now at 65mph. The most it is off at slower speeds is 1mph or less. Works nice and smooth after a good lube on the speedo head and warner box.