yeah, smaller tires will help significantly.

How much, I can't tell you;
anecdotally, going from 31's back to 235-75-15's got me from 3rd to 4th gear climbing a couple of local hills.
That translated to road speeds going from 35-40 up to 55-60. But that's a Gen 1 manual...

fwiw,
Toby


'89 V6 4dr- '4- Doris'