change up - change down or leave

[merrymike]

Hi,

I have owned Mr K for many years and had his motor reconditioned (now 2.1L type 4) a year or so ago, so there is plenty of torque (its all relative of course ).   Many times when driving I find,  on a gentle hill at say 60km 4 gear means the engine is handling it ok but working hard, whereas 3rd gear means he is revving fairly high ( sorry about all the generalities)

So.......my question is .....is it ok to let the engine operate under obvious load for short distances or go for the higher revs to take the load off it and suffer the higher revs (and wear?)  My understanding is as its air cooled, labouring at low revs means less air cooling from the fan which pushes engine temp up and increases strain on engine components.

cheers

Shifting back to 3rd when going up a hill at 60 km/hr will put your revs up to where the engine would be spinning in 4th at ~90 km/hr.  So you aren't flogging the crap out of the engine by shifting down in that use case.

If you have a type 4 gearbox the 4th gear is pretty tall, 0.889, so unless you're on level road, you'll be working it pretty hard.

As a rule of thumb, if I find I'm driving up a hill in 4th and the engine can't maintain the vehicle speed, or I have my foot flat to the floor and it's "just" keeping it, I'll drop back to 3rd.  I'm happy to go up to 80km/hr in third up a hill. 

I would recommend getting a 123TUNE distributor as well - it can shift the timing on individual cylinders by a +/- a degree so your engine is a lot more balanced, quieter and smoother at higher revs.