Caterham suspension setup & tuning options

[CaterhamSVT]

I have a Caterham SV with the wide track front suspension and Bilstein shocks, and I'm trying to understand the different suspension options available. I'm running the 16 inch tires and wheels.

 

Caterham's web site lists several front and rear suspension options, but gives zero information on each one. Even basic information like spring rates, and the adjustability of the valving, etc. is completely absent.

 

My car currently has low ground clearance under the sump, and the lower A frames actually slope upwards away from the chassis to the uprights. This is not ideal geometery, the A frames 'should' be parallel with the ground for best handeling. Is there a (good) reason the car is setup like this?

 

My plan is to add the adjustable spring perch kit to my existing dampers, but the parts for this kit are backordered. I see other options exist, but I have not found any information to make an informed choice.

 

Does anyone here understand the differences between the several different sets of coil overs available through Caterham, or from third party suppliers like Nitron?

 

Also my car is currently setup with a fair amount of rear toe-in (1.5 degrees). This seems like a lot of toe-in for such a light car.

 

What suspension setups do people reccomend for these cars in street, autocross, and road-race applications?

 

A suspension setup FAQ would be a great asset.

[sparecr]

I had a long conversation with the guy from Canada that sells the Busa powered Cats a few weeks back. He was at the track helping a customer set up his car. He seems to have a lot of knowledge and many different set up options available. He has an owner down in Mississippi. regular disclaimer appllies as I have not used his stuff or followed his advice so...

 

I have his contact info at home if you need it.

[Guest speedcraft]

Give ben a call in Denver or Chip at GT classics...great sources for advice based on their own and customers experiences.

[xflow7]

Though not continuously adjustable, some of the Bilsteins use a circlip that forms the seat for the spring perch with 3 or so different grooves in the shock body that can be used for the circlip. This obviously doesn't allow sufficient resolution for corner weighting, but it can provide a coarse ride height adjustment. You might have a look to see if your present Bilsteins have this arrangement and can be set to a higher ride height on the front end.

[Ian7]

This is not ideal geometery, the A frames 'should' be parallel with the ground for best handeling.

 

not sure I'd agree....

the 'best' geometry depends on what handling characteristic you want to emphasize, and depending on where the suspension pickup points are located (inboard and outboard, front and rear) will define among other things the chassis' dynamic roll centers. The static A-arm angles resulting from this may in rare cases be parallel, but its very unusual for the best compromise set-up to not have converging angles.