Re-gearing for 33×12.50 15 tires.

[Whistler62]

I have a 1984 B2. 3.73 gears. I lifted ir 4 inches and put 33 inch tires on it. What is the preferred gear ratio for these tires? I rebuilt the 2.8 and went to the dura spark set up. New carb and no smog junk. Runs great. Just a little under powered now. Thanks for any help.

[Dustin_Oregon]

In terms of easily available ratios, I’d go with 4.10.
Check out the chart here for more detail. Cheers




“ The chart is divided into three categories. The rpm highlighted in black are optimum for the tire size and ratio combination. These will most closely give you the best overall drivability. If you're looking for a ratio that will give better fuel economy for highway driving at the expense of some acceleration and overall performance, choose a ratio in the yellow shaded area. If you're looking for a ratio that will improve acceleration and towing power at the expense of some fuel economy, choose a ratio in the blue shaded area”.

[Whistler62]

Thanks for your help. I appreciate the pic of the chart. Very helpful.

[WheelieWanda]

I have a 1984 B2. 3.73 gears. I lifted ir 4 inches and put 33 inch tires on it. What is the preferred gear ratio for these tires? I rebuilt the 2.8 and went to the dura spark set up. New carb and no smog junk. Runs great. Just a little under powered now. Thanks for any help.

For running 33-inch tires on your ’84 B2, a common gear ratio upgrade is to go with 4.10 gears, as Dustin mentioned. This should help restore some of the low-end power you feel you’re losing with the bigger tires. If you find it still feels a bit underpowered, especially on climbs or when towing, you might even consider going up to 4.56 gears for better performance, though you might sacrifice a bit more fuel economy.