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

Rear Suspension

The rear suspension is now taking shape. I was beginning to think that I would never find a Sierra Diff! Nearly a year of surfing and hundreds of bids later, I have a gem of a diff. When I opened it up, there was zero signs of wear and the ...

Coil-over Shock

Motorbikes are a great source for coil over shock absorbers! Just be careful about spring rates. The '94 Yamaha R6 has some great shock absorbers but the spring rates are too high for a Locost or Haynes Roadster. Various sources suggest as low as 260lbs/in for smaller engine cars ...

Fully Adjustable Rear Suspension

I had a month out from blogging, but that didn't mean I was idle. Everything I had done on the rear suspension had been removed, re-done, then tweaked, then modified and finally mocked up before I went ahead and fully welded everything. The first problem I had was I wanted ...

Anti Dive Geometry

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Ford Sierra Front Stub Axle

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