Coilover spring rates

[youngprodigys]

Hiya everyone.

not quite sure what the weight distribution is on a G40??? 60/40? 55/45? anybody know?
has anyone put there G40 on a weigh bridge and got the weight over the front wheels?  (i know this includes unsprung load)

and finally - what spring rates do people use on there coilovers? its not strictly for G40s what im researching this for but you guys are more likely to know with a few racing these around tracks.

on my G40 before i moved to air ride i was running 310Ibf/in ones and thought the ride was ok,

if you run your car lower you will need it to be higher to stop you smashing the bump stops all the time so im thinking 310 might be sweet if your running at -80 and lower, but a bit stiff if your only running -40

whats your inputs guys???

KiZ

[dub-disaster]

I ran 230lb 7" springs on my h&r collies and they where good although spring length was a bit short in my opinion, the Gaz I just ordered came with 7"250lb springs. It with 4" of travel they required 40mm progressive bumpstops which they would of been riding in all the time, I have since had a longer piston with 6" of travel put in and intend on running 8-9" 225lb springs for the road but only 15-20mm down.Have to work out your static droop piston travel at desired ride height etc..etc.. To ensure you don't reach coil bind before bumpstops and bumpstops before chassis hits the floor.

Gaz recommended me between 250-275 for road use with a short travel damper and a progressive bump stop they recommend 300-350lb for track day/race all these are the front springs. With. 7" length.

I have gone for 180lb on the back 10" long seem reasonably comfortable still with good turn in but havnt realy had a chance to realy push them hard yet. But 160-180 has been recommended by a couple of people so far.

Also worth noting that with a ppp frame no arb so the spring rate should be upped to compensate Yoof has suggested 7.5" 250lb spring as a starting point. I intend on running longer softer springs on the road and having some shorter stronger springs for any track days I do (probably 275-300lb 7-8")

High pressure gas dampers  (such as bilstiens) will add a little spring rate maybe 10-15lb due to the high pressure gas aswell or so I've been told!

This is all I have learnt recently hope it helps and by no mean take it as fact as I am by no means an expert!

[youngprodigys]

thanks fella. some good input there.

one thing i cant work out- why mk1 golf rear coilovers come with 320ibs/in rear springs? if what you say is right (sub 200ibs/in) then mk1 coilies are bloody miles out! id love to hear from anybody who has rear coilovers fitted from PhilJ, ta tech etc etc and know the numbers on there springs.
i have 6sets of different mk1 springs from lots of manufacturers and they are all around this value- but in different lengths/No of coils, coil thickness - but all end up the same

[dub-disaster]

Does seem pretty high on the back unless you like a realy stiff back end !!!( no pun intended ) I think this would make the back end a bit twitchy on bumpy roads and make the car want to swap ends not to mention a pretty horrific ride quality.
Thing to remember here is if shortened damper pistons are used very short bump stroke is availible as little as 1-1.5" sometimes and in this case a quick fix is very hard springs to reduce droop travel and increase bump, this said I can't see there being a problem on the back as there's usually loads of travel due to no size constraints on the damper length.

[hayesey]

I'm just ordering some 375lb 7" springs for my fronts for oulton park next week.  Currently have 275lb ones and they are too soft for track.  Probably OK on the road.  This is with a subframe so no ARB.

[Tav]

I went with what Alex has on his G40 from Gaz.  Road setup 225/165 if I remember rightly.  I went for this as there's always the options of upping the rear rate nearer/same/more than front rate.  I can't see me needing more than 225 on the front for compliance and I have the ARB.

There's not a lot of info on Polo suspension setup so this thread could be a good thing...

[Alex]

Mine are 275lb 7in at the front, 165lb and I can't remember how long at the back.

[z3i]

Ive got 180lb at the back, can't remember length, but keep getting some scrubbing from my wide wheels even though the coilover is wound as far up as it will go, big arch gap. Ride qaulity is nice but I want to go a bit lower

Got 250lb on the front, going to join alex and go 275lb
Think 200lb on the rear would be decent? And maybe an inch shorter?

[z3i]

http://www.rallydesign.co.uk/product_info.php?products_id=9330

the ones on g40 are 2 and a quarter inch arnt they?

how does a shorter spring effect the handling characteristics

[z3i]

whats the internal diameter on the front? sorry for all the questions

[Tav]

I'm just ordering some 375lb 7" springs for my fronts for oulton park next week.  Currently have 275lb ones and they are too soft for track.  Probably OK on the road.  This is with a subframe so no ARB.

How did you find the 375's?

[hayesey]

Not tried them yet!  Am in the process of an engine rebuild and front suspension rebuild.

My problem is going to be getting some suitable dampers, currently have Koni inserts and they aren't really up to the job of the 275lb springs.  I'd like some cup-car style shocks but as soon as any are available yoof buys them  

To be fair I think any still knocking about are totally knackered and unless anything has changed yoof didn't seem to be able to find anyone willing to rebuild them.

[hayesey]

I did get a price for getting some custom bilsteins made up but it was so expensive I'd be better off just getting some Gaz coilovers.

[Tav]

I didn't think getting some Bilstein B8's re-valved would be too bad?  Especially since you have the coil over conversion in place already.  Seems like shopping around for rebuilds with worthwhile, certainly the companies that do the Clio Sachs vary greatly.

I'm talking with AVO about making 40mm monotube Mk1 Golf style struts with the Polo steering arm grafted on.   Single/double/triple adjustable (I think I'll go with double) and remote reservoirs on the double or triples (might as well have the remotes whilst at it).  The struts will be new fabrications, unlike the eBay conversions will make it easier to size for the car and ofcourse means AVO can slip in their insert without worrying about trying to fit someone else's housing.

I've got unused Gaz holding the car up now and I'm sure they'd be great, but I've always wanted the Mk1 Golf hubs and Monotubes, just found it hard to get Bilstein/AST etc. to seem interested. AVO are quite keen and my mate Gus has them on his 106 Rallye with good results.  Hopefully means I can use the top mounts for castor and hubs for camber.  That way can maximise available castor whilst keeping chassis original.

Price...not cheap though....in the H&R+ bracket.

Perhaps they would be interested in making an insert for the Polo strut, would need to take the internal diameter and see if that's compatible with their inserts.  Without the housings the price would be a lot more agreeable too.

They also offer strut conversions much like what Gaz do.  Again another possibility, though I don't think they'll have done a Polo yet.

[hayesey]

At the time I was talking to them about revalved and also shortened so I could shorten my struts by 25mm too.  Price was getting to something like £400 for just a pair of front dampers though. 

If you decide to sell your gaz coilovers I'll have them