Locost Haynes Roadster Kangaloosh Front Suspension

Front suspension design has been complicated by the 4×4 running gear.

It quickly became obvious that it would be impossible to use the ubiquitous Ford Mk2 Escort steering rack as it would try to pass straight through the Sierra Front diff.

The push rod for the coil-over shock also tried to occupy the same air as the outer c.v. joint.

The rear suspension is complicated by the fact the drive-shafts are different lengths and the c.v. joints have much less ‘play’ in them. Basically, they can only grow a few mm in length as the wheel travels up and down. From a handling point of view, both sides need the A-arms to be symmetrical, but this means each sides drive-shafts will grow and shrink unequally with wheel travel.

Despite the obstacles, after going back and forth between Kangaloosh and AutoCad several hundred times, I think I am there!

Well, almost! There are still a whole load of brackets to draw up, but that’s the easy bit and I will feel happier if I can plot the rising spring rate. I need to work out the pre-load / shock compression – I might need to tweak the push rod bell cranks on the cantilever shock arrangement. etc etc etc

What I have done with the A-arms, is to use a bunch of 5/8″ Clevis joints. These enable loads of adjustment of practically all suspension parameters.

For parts, check out this site :


For the suspension parameters I used, see this page:


If you haven’t seen Kangaloosh or SuspEdit – check them out now! They aren’t just toys used by the gaming community to model cars, they are highly sophisticated pieces of software. Real race teams use this software to model their cars. They can see how certain suspension set-ups perform on various race tracks.

When you download Kangaloosh, you get a set of sample cars. They are all various Caterhams! I’ve used these as a base point for my modelling. This set-up is obviously different, but the figures are ‘in theory’ quite similar and in places marginally better.

Half Track Variation (Scrub)

Locost Half Track Variation - Scrub

Roll Centre Migration

Locost Roll Centre Migration

Camber Gain

Locost Camber Gain



Bump Steer

Locost Bump Steer

Bump Caster

Locost Bump Caster

Steer Jacking

Locost Steer Jacking

Steer Camber

Locost Steer Camber

Multi-link Steer Caster

Locost Multi-link Steer Caster

Multi-link Steer Scrub Radius

Locost Multilink Steer Scrub Radius

Multi-link Steer Contact Patch Trail

Locost Multi-link Steer Contact Patch Trail

Multi-link Steer KPI / SAI

Locost Multi-link Steer KPI - SAI