Power to weight ratio

[MeonIan]

Hi all

I currently own a Skoda Octavia 1.9tdi 105 bhp as a towcar, very happy with but am now looking to upgrade my caravan to the S6 Ranger 460/4 MTPLM 1208kgs.My handbook says my cars kerbweight is 1500kgs but whattowcar says 1395kgs, maximum tow is 1400kgs, so all seems okay there. My one concern is whether the engine will be okay for a combined mass of car 1900kgs laden and van 1208kgs. I seem to remember somewhere there was a number of bhp recognisable as good per tonne of towed mass. Any opinions welcome.

 

[ProfJohnL]

Hello Ian,

Your car manufacturer has already established what your car can technically handle. If your new caravan falls within the manufactureres limits, then you will be ok.

However the more torque the engine can produce the better it will be.

 

[ProfJohnL]

Hello Ian again,

I should have added that simply keeping the weights within limits does not guarantee the outfit will stable or tow well, that is down to other factors such as how the load weight is distributed. nose weight, ad driving standards.

 

[RogerL]

A bit like cars solo, adequate performance means different things to different people.

The Caravan Club recommend a minimum of 40bhp per tonne of train weight BUT this is a long-standing recommendation from the days when everyone used petrol or non-turbo diesel engines. Many caravanners with turbo-diesels are quite happy at less than that figure.

Car manufacturers towing limit is based on a number of factors including hill start ability - using the full limit can give sluggish towing for some cars.

Whether diesel or petrol, power-to-weight ratio does have significant effect on acceleration and hill climbing ability.

Calculate your current train weight compared to your proposed train weight - if your train weight will be 10% higher than before, your acceleration and hill-climb speed will be 10% less - if that's acceptable to you then go for it.