Spring rates for R400

[DSL]

Any thoughts as to what spring rates work best for mostly track days & sprinting on R400. At the moment just have the standard ones fitted that came with the car which seem fine for the road but a bit squishy on faster corners whilst on track.

[Jason Plato]

250 > 300 lb front

125 > 175 rear

 

orange bar front

 

1/2" bar rear

 

😬

[RESOLVIWOLF]

exactly what the race series use

250/215

 

a soft rear is for wimps and/or failsafe understeer mode

[Mike Bees]

Or those who like traction on non-racetrack-smooth surfaces...

 

Mike

[Paul Bowden]

My superlight has standard springs/dampers, what ever they are, (150 Lb front?)and this does appear to be a disadvantage on race circuits. However a number of the sprints I compete in are on air field type circuits, and here the story is very different. My car is very good over the less than smooth tarmac/concrete and I seem to be at a major advantage. My times are better than alot of the quicker ( more power/slicks etc) cars. When you watch the action, and hear comments from others after my car has been out. Where everyone else seems to be air borne and hence needing to brake etc, I do not even feel the bump and just drive through it. I should add that this is a car set up thing and nothing to do with me If you knew what you were doing with damper settings and adjustable rates you could have the best of both worlds no doubt, but no one I compete against seems to have got this right, of course you get very little opportunity to change set up at a sprint.

I realy believe higher spring rates can be the wrong move, but who am I to say.

[DSL]

Thanks guys, as per everything in life I guess its a bit of a compromise situation. So have left it in the capable hands of Caterham Midlands to sort me out with their recommendation of the same springs that the road sports inters(?) are using. Possibly 250lb front & 215lb rear (from memory)

[Mike Bees]

You're not wrong Paul. I remember one of the first sprints I ever did, which was at North Weald (quite bumpy) a spectator told me that someone had sagely said to them whilst I was rounding the 180 degree bend nearest the paddock "you see that car, it's just too soft" - well if it was then it was also just too fast and nothing to do with the newbie behind the wheel. As you say to get grip you need your wheels on the ground. You don't see m/any successful hillclimb cars running stiff springs.

 

Mike

[RESOLVIWOLF]

if traction is an issue and surfaces are less than ideal then run a soft setup all round then ..... but not stiff + soft

[david nelson]

I think the rates that Dave J gave ar spot on. I had my sl set up with 250 front and 215 back. Well on road in the damp it was imposable to put down the power and its only 140 bhp. On track it was fine.

 

I changed to 250 150 as competing in hill climbs and sprints much better. On road also was safer, I could put power down in the wet without the back stepping out all the time.

On track I have also been happy with this set up.

 

hope this helps

 

 

David

[Casbar]

Supersport R.

 

Front 275

Rear 225

Red front arb

Rear Blue 9/16

 

Bilstein M0 dampers

 

Car was setup by Arrowstar, haven't had any issues with back stepping out in the wet, but then I probably don't drive on the limit on the road, save that for the track.

 

Ride is still better on the road than my old xflow live axle

[A10ROX]

I run the 250/215 set-up

wheel geometry also critical

 

Tyre choice is the most critical

Mine is mostly track, no sprinting, wet with wet tyres is absolutely great 😬

Slicks in the dry

 

There is a problem with cold and damp

 

 

 

A10ROX:OK, its an R500 without the magnesium bits sump etc and only 205bhp!

[Mike Bees]

A 250/215 combo will give you a considerably stiffer back than front, due to the angle of the front dampers - I think the effective front wheel rate will be around 160lb/in?

 

Mike

[Jason Plato]

the 215 rears are realy for slicks to cut the front understeer. You should also consider the dampers you are running in combination. The M1 Billies are realy solid . I realy wouldnt fancy this combnation on the road .

 

If you reckon your ride is OK with these rates then you realy should try a different setup on the road and see what you are missing out on

 

Dave