Cruising at 110 km/h in a Bay: 3.88 or 4.12 R&P?

Cruising at 110 km/h in a Bay: 3.88 or 4.12 R&P?#1 · 9/23/2026, 8:22:06 AM

'76 Westy, 2.0 type 4, 185R14 tyres. It labours on long motorway climbs in 4th. Should I go shorter on the R&P, or leave it and live with the 3rd-gear hills?

Attached transaxle build: Westy current box

R&P: 4.86
Gears: 3.78 / 2.06 / 1.26 / 0.82
Tire: 185/80 R14
Reduction: 1.26

Re: Cruising at 110 km/h in a Bay: 3.88 or 4.12 R&P?#2 · 9/23/2026, 12:22:06 PM

Put your exact ratios in the transaxle calculator and look at the drop from 3rd to 4th. That's where your problem is. A bus with a tall 4th falls out of its torque band on a hill, and then you're dropping back to 3rd.

Keep the cooling in mind too. You want the revs high enough for the fan to move plenty of air under load. Lugging up a long grade is bad for your head temps.

Re: Cruising at 110 km/h in a Bay: 3.88 or 4.12 R&P?#3 · 9/24/2026, 10:22:06 AM

Good point about the gap. Going to run a few combos and report back.