View Single Post
Old 12-26-2013, 03:01 AM   #51 (permalink)
freebeard
Master EcoModder
 
freebeard's Avatar
 
Join Date: Aug 2012
Location: northwest of normal
Posts: 22,661
Thanks: 6,357
Thanked 7,270 Times in 5,915 Posts
Quote:
my biggest problem is over hang at rear. estimate front to rear weight balance is 30% front and 70% rear. chassis was orginally designed for max gross weight of 2-2 1/2 tons. my motorhome weighs 2.8tons unladen
My weekly driver weighs 1980lb with 840lb on the front axle, that's more like 40/60, but similar. Pressing the limits like that, I'd want good brakes. Widen the rear track as much as possible, even a few inches with deeper offset wheels will help. Stiffen the rear in anti-roll and double up on the rear shocks. Fine tune by unbalancing the tire pressures.

I guess you can't extend the front any more than the rear. Your situation is similar to the box van (lorry?). You might take a look at: Advanced Aerodynamic Devices to Improve the Performance, Economics, Handling and Safety of Heavy Vehicles

Advanced Aerodynamic Devices to Improve the Performance, Economics, Handling and Safety of Heavy Vehicles

Quote:
These experimental results show overall aerodynamic drag reductions on the Pneumatic Heavy Vehicle of 50% using only 1 psig blowing pressure in the plenums, and over 80% drag reductions if additional blowing air were available. Additionally, an increase in drag force for braking was confirmed by blowing different slots. Lift coefficient was increased for rolling resistance reduction by blowing only the top slot, while downforce was produced for traction increase by blowing only the bottom. Also, side force and yawing moment were generated on either side of the vehicle, and directional stability was restored by blowing the appropriate side slot. These experimental results and the predicted full-scale payoffs are presented in this paper, as is a discussion of additional applications to conventional commercial autos, buses, motor homes, and Sport Utility Vehicles.
I'm thinking elecic leaf blowers tucked behind the rear bumper. And there's lots of opportunity in the cab door and mirror area.

  Reply With Quote
The Following User Says Thank You to freebeard For This Useful Post:
chefdave (12-26-2013)