Power Losses (temp & altitude)

[Diesel Dave]

Just found some details on power losses for small diesels associated with heat and altitude.

2% reduction for every 5 deg over 20 deg.
1% for every 100m above sea level

On top of this individual motors vary by 5%.

So my lowly 9hp Lombardini could be just 8.55hp to start with, as London has hit 30 deg this last week this robs a further 2% leaving just 8.38Hp to push along with.

Makes you think about those planned adventures - crossing the Pyreneese fully loaded with just 5.87hp left (3000 metres) might mean a fair amount of time on first gear.

Right - where did I put that little turbo!

Dave

[Sphere]

Need more watercooled small blocks, for Enfields etc. Another plus is that they should be less noisy.

[oldbmw]

When I toured th e pyrenees 3-4 years back I was surprised how fast it got cold going up those mountains. varied from 30+c to 6c in matter of minutes, so there may be a little bit of temperature compensation for altitued

[andrewaust]

Bugger No trooping over the Barrington mountains for me then when the temps hit 40deg . I can see it now, drag racing the tourist buses up the hill, heaps of black soot wondering if first gear will be low enough !!!!!!!!!!!!


A

[arnaud]

Hmm didn't notice it in the Alps.. With passenger and luggage you have to shift back a lot in the mountains..
After a while you don't have a good sense which inclination is bigger..from 3 to 2nd.. no worry
Lots of torque, no heat problems..
I think it's important to keep it revving not too low and shift back in time.

We plan to go at the end of this week.. wherever it is sunny..