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Probably thats what I will do, chuck in softer springs and since its a street car only now, if it goes alright, I will just leave it. I have yet to get verniers and come up with a more accurate measurement of the spring wire thickness though..

No, when the vehicle is on the road, the helper springs should be squashed to binding.

I wouldn't put softer coilovers on teh rear only. If your fronts are like 12 or 13 kg/mm, then the BC rears at (say) 8kg/mm will be too soft (by comparison) and the car will understeer like a bitch. You might make it work if you pulled the front ARB off it and ran a fairly thick (like 22 or 24mm) rear bar.

Ok so got verniers today for extra accuracy.

Spring wire dia is 12.5mm

Spring outer dia is 89-90mm

No of 'active' coils is 6

Spring rate from a couple of US sites is 9kg/mm and thats for the rear- f**king hard hehe

Fronts are 10.7kg/mm at 13mm wire thickness, all else same.

Should I run n get 9/7 springs as two sizes down are acceptable or should I go out of bounds n get 8/6 which is still hard??

I would buy a set of 6/4 springs and try them. They'll not set you back too many $$ and you can probably offload them to someone else if they simply don't work against the dampers. But if perchance the damping is not ridiculous, then you may just end up with a very firmly overdamped ride, which you could at least live with more than the simply rock hard ride that you'd have now.

Plus, you may be able to sell your current springs to a track junkie.

I went from 10/8.5 down to 8.2/6.4 and they're still very stiff - too stiff with the crappy roads i use. It was a noticeable improvement tho. So - IMO 9/7 is a complete waste of time, 8/6 would be the hardest you'd want to think about changing to, though i'd guess less than 8/6 would suit you better.

Thanks man, you guys are brilliant, Otomoto is 5mins from my place and have the HSD springs in various rates which look about the right size as well, 200mm long, 65mm Inner dia etc; now the dilemma is whether to go 6/4 or 7/5 from 11/9 which is a huge drop - you all have different opinions - I would love 6/4 but dunno if the dampers would cope, 8/6 would be more matched but then its too hard so :wacko:

  • 3 weeks later...

Update: bought 5kg HSD springs from Otomoto, dismantled rear ( a real pain of the job in the dark with no ratchet spanner for rear coilover bolts- really hard to access those f$&@ers), well finally put them in. The HSD coil inner dia is about 1.5mm larger than the Cusco coils so there is some left-right play against the top n bottom sleeves. Texted Jez and he said it should be ok- legend. Put it all in ( fronts are still Cusco 10.8-11kg springs) and went for a drive, feels somewhat softer and DOES grip better - less wheelspin in first and second and more traction but not by too much, but a reasonably good improvement I would say. Doesnt ride funny or bottom out as I had thought with damper n springs not matched right.

The car sat like 7-10mm lower after I installed the new softer springs in with coilover height untouched and spring preload about the same hand tight. So I raised it up that much to get more travel for the struts and less -ve camber for the wheels- win win. So I have yet to change the fronts- to 7kgs. Thinking I might go 6kgs as 5kgs from 9kgs for the rear didnt screw up my damping..

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