corner weighting

[ianminki]

hi rob and all
now back in the garage after putting new wheels on the car still 15inch with toyo t1rs with 18psi tyer pressures. im still not happy with suspension setup the dampers are spax 13inch open and 9inch closed with 8inch springs 180 front and 130 rear .I have been reading on here about corner weighting and would like to know more about how its done and the benefits from it .as I don't race or do track days is it nessasery any help would be useful regards ian

[stylussprinter]

hi rob and all
now back in the garage after putting new wheels on the car still 15inch with toyo t1rs with 18psi tyer pressures. im still not happy with suspension setup the dampers are spax 13inch open and 9inch closed with 8inch springs 180 front and 130 rear .I have been reading on here about corner weighting and would like to know more about how its done and the benefits from it .as I don't race or do track days is it nessasery any help would be useful regards ian

If you don't intend tracking the car there's no real point because the gains are found at the extremes of performance/handling. However , setting the car up well , will be an advantage and can be felt on the road straight away. The first thing being that 13 inch shocks up front are too long . You need 11 inch with a 7 inch spring . Obviously your lightweight bike engine means the spring rate can be lower than most but I would still use 200 minimum possibly 225 lbs up front. The rears you may get away with using the 13's and 8 inch spring but put the 180 lbs front spring on.
Once you've sorted that , ride height can be set . Ultimately the shock lengths/spring lengths and spring lb rates will determine how low you can set the car , without running out of shock piston travel --- just decide where you think it looks and sits right THEN check all pistons stems for remaining travel visable on front and rear shocks --- you'll need a good torch and mirror at the rear.
FRONT --- not less than 10mm piston visable under bump stop.
REAR ----- not less than 30mm & more is better.
Set RAKE at 25mm (ie. rear under seat pan 25mm higher than the front under lower chassis rail. Try setting ride height at 140mm front 165mm rear as a starting point THEN adjust to suit shock piston ammount still available.
TYRE pressures ---- your car being very light I'd run 16 psi all round . I'm running that with my 575 kg car .
All the above is a basic starting point but should give you good handling along with 1.5 neg camber front and castor 3.5 degree minimum.
Hope this helps Ian
ONE MORE THING ---- Shock clicks front = 1/4 to 1/3 rd of total clicks
rear = 1/2 to 2/3 rds total clicks Basically the higher rates for tracking the car.

[pigeondave]

Hi,

Not knowing any of your cars history but it might be worth getting the dampers checked in a damper dynamometer.
Procomp http://www.procomp.co.uk/ have the facilities to do this and from what I have read on the net appear to be extremely competitive on price.

They can also advise on spring rates and corner weighting.
I like to have a fiddle with things on the car but sometimes its quicker to take it to someone that had years of experience in setting up these cars so that you get the best out of them quickly and spend more of your time driving it.

Be warned that they will poo poo the top rocker style of suspension, saying it has no advantages and causes the dampers to heat up as they're blasted with hot air from the rad and therefore changes the viscosity of the damper oil. But they will set the car up as best as they can.

Search for the reviews on Southern Kit Car Club (SKCC) and locostbuilders.

http://www.locostbuilders.co.uk/viewthr ... tid=182242
http://www.locostbuilders.co.uk/viewthr ... tid=181596

I have had my English axle adjusted by them to give better geo and was very impressed. When I get the car back after upgrades I will be booking it in to see them.

[ianminki]

hi all
thanks for that info .will look at some new dampers for the front and maybe taking to have it setup I dident realise I needed shorter dampers to front as all that came with the car and thout it was standerd issue thanks againe regards ian

[stylussprinter]

hi all
thanks for that info .will look at some new dampers for the front and maybe taking to have it setup I dident realise I needed shorter dampers to front as all that came with the car and thout it was standerd issue thanks againe regards ian

It 'was' standard issue years ago but I have spent many years developing a decent set-up and it's all wrong using those lengths . Obviously my own set-up is specific to the track but many stages were gone through along the way -- one being a good road set-up then competition set-up followed using various lbs lengths of springs then shock lengths etc etc.