coilover spring rates for track car?

hi,

i have a second hand set of avo coilovers from a mk2 16v to go on my track car, on removing them from the donor car i found that the 2 fronts were fitted with different springs with the platform on one wound higher than the other to componsate.

i've stripped them ready for overhaul at avo and will need to buy new springs but what rate springs should i get?

i think they come with 250lbs on the front and 200lbs on the rear for fitment to a road car. but should i try uprated springs for my track car?

i would like a balance between on track handling but still be drivable on the road, (ie not too harsh so i can still drive it to/from work etc on occasions).

anyone help?

thanks

 

The springs are only about 20 each so you can have a bit of a play.

I'd say if you're running uprated ARB's then I'd stick with the standard rates that came with the coilovers.

It depends how far you want to go. One of the old Slick 50 racers says they'd use 250Lb fronts as their softest springs so I guess they normally run 300 or more. They also run it super stiff at the back, up around 1000Lb's for some races apparently.

I'd say maybe go for 250's front and rear.

Joe

 

.. or if the rears you have are ok, then just get new fronts .....

Here's a spring company I found, some interesting info. You can get their sprigns from Merlin Motorsport based at Castle Combe.

Faulkner's Race Springs

Joe

 

Some people use 500lb on the front and 600lb rears, with Eibach ARBs

Don't know what they are on my FKs [:^(]

 

500Lb fronts must be a "touch" harsh on the road tho

Original 16v Fronts are 130Lbs!!

Joe
Edited by: Joe_G

 

cheers joe, some good info there, 20 for a spring isn't too bad so i could experiment,

gvk, i have eibach arb's fitted, 500/600lbs sounds like a fair jump over the standards, do you think that would be too harsh for raod use?

 

Ask Barny, it's probably why he trailers his to the track days now

I'd try 300 front 400 rear,see how it is then, you could always experiment with harder ones if you wanted to, the harder springs will reduce the roll even more than the Eibach ARBs do.

I'd like to experiment with the springs on mine, but as I drive a lot of road miles, it's harsh enough as it is now, with the road spring rates fitted to the FKs ( whatever they might be)
Edited by: G_V_K

 

Well I have an article here from '96 with 3 coilover kits in and the spring rates are stated as ....

SPAX - 200 Front, 150 Rear.
AVO - 200 Front, 180 Rear.
JAMEX - 230 Front, 170 Rear.

Can't gauruntee the accuracy of these but they sound about right.

I'd say you're better off with a softer spring to start with as you'll still be learning the car and the correct lines etc. so you'd be better off with something fairly progessive. You can concentrate on keeping a smooth driving style then and when you're going that much faster that you need stiffer springs then go for them.

I'd say 250 Fronts and whatever rears you already have would be easily stiff enough initially.

The Racers have super stiff rears so they can turn in aggressively then control the yaw of the car on the throttle through the corner meaning they're on the power earlier, this might be best for lap times etc. but it's also an easy way of binning your car if you're not used to it!!

Joe

 

i'm taking the coilovers to avo on thursday so will find out exactly what was fitted and then decide what to do,

i have to buy 2 new front springs anyway as they are an odd pair

don't think i'll go as high 500/600 but will def go higher than standard for a road car. might try the 300/400 set up you suggested,

 

went up to AVO at northampton yesturday to drop off my coilovers,

the guys working there are very friendly and helpful,

they are doing a full rebuild on all 4 changing all the chromed rods and internal seals, replacing all the nuts/bolts etc. and will uprate the internal bump rate of the fronts to suit a track car.

the springs they recommended were 350 for the fronts and 250 for the rear. so i've gone with that.

should all be done in a week and sent back to me,

felt it was worth the drive up there to drop them off so that i could see the facilities they have and actually speak to someone face to face, glad i did.

ordered some poly top mounts for the rear from bigboy's toys and will sort out some new front top mounts today, so might have them on the car next weekend...

 

That's cool, I'm just wondering if you've considered an upgraded top mount as with that sort of spring rate, I'm not sure standard ones will be upto the job.

TAS make one which is very good I believe and allows you to adjust the castor as well which has beneficial effects on the handling.

Otherwise, I'd go for the G60 top mounts and see how long they last.

Joe

 

not too sure about the front top mounts,

waiting on a reply from C&R to find out if their kit combining mk3/mk4 top mounts with the seperate bearings will fit my coilovers,

if not i was going to go for G60 ones, but will look into other options, never heard of TAS do you have a web site link?

 

TAS - Trans Auto Sport

I think PhatVR6 swears by them.

They're eccentric so by turning them, you can alter the castor.

Joe

 

cheers joe,

the link works but see the prices you need to register and the web site won't let me

 

found this on the shine site:



$225 for the kit, ideally needs to be welded on but can be bolted, need to cut the top off from the cars strut mount, up to 3 degrees of adjustment.......
Edited by: steve r

 

Blimey, hardcore!

Not bad for $225 with the exchange rate as it is!

Just need to avoid the import tax .....

Joe

 

been thinking about it, i work for BA so could fly over pick it up and bring it back in my hand luggage.......

 

and at $99, how about these for the rears:




'Sphearical bearing eliminates play from the rubber bushing while allowing the shock to pivot unlike polyurethane.'




Edited by: steve r

 

i think maybe peeps need to come for a normal drive in mine before they dismiss my spring rates...

The car is trailerd now partly due to the fact its uncomfortable to drive over long/very long distances, gvk has said to me his racing seat gets numbing after a while. The other problem is we take so much stuff with us that it makes the car more tiring to drive laden with tools and wheels etc. So i borrow a trailor and have a cheap tow car and arrive at the day a LOT less tired than i used to.

I did curby and donny in one weekend last year - normally i would have been f**ked after the first day but i wasnt and i'm glad i have taken this route.

The car itself is fine on the road with 45 profile tyres as well, obviuosly its stiff but not as bad as you are imagining (we wont mention how much i hate my dampers etc .....

 

Oh and steve put the stiffer spring on the back not hte front....

The avo boys keep telling peeps that way round, but trust me fit it to the rear!