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spring rates
beaver34 - 5/1/09 at 07:31 PM

hi there, and ideas what the best spring rates are for a kit car, im new to this kind of thing and are wanting abit of input really, the car is an ex race car so im thinking it going to have quite hard springs on there, they are gaz shocks, and have a 7 no. on them but couldnt see anything else, i presume this is the uncompressed length, this is the car, cortina front, and english axle on the rear,


thanks alastair


beaver34 - 5/1/09 at 07:32 PM

i presume weigh pays a fair part, with a full tank ive been told it was £520kg, thanks again


Hellfire - 5/1/09 at 07:39 PM

If you remove the spring from the damper, the rating should be engraved or painted on the end. Check what the current spring rates are and work from there.

Phil

Incidentally, why do you want to alter the spring rates? Is the ride too firm for your liking?

[Edited on 5-1-09 by Hellfire]


beaver34 - 5/1/09 at 07:43 PM

o.k ill do that, a carnt answer that question as ive not driven it as yet im still putting it back together, but im just assuming that it will be stiff and was trying to get a ball park figure that people use, thanks


Hellfire - 5/1/09 at 07:56 PM

Unfortunately it's not quite as easy as that. There are a lot of considerations to take into account and most manufacturers kits are constructed slightly differently, so whats good for one, won't be any good for another.

There was a spreadsheet doing the rounds to calculate the spring rates required for a given application but not sure if it still exists.

Phil


mr henderson - 5/1/09 at 08:18 PM

quote:
Originally posted by Hellfire

There was a spreadsheet doing the rounds to calculate the spring rates required for a given application but not sure if it still exists.



Mike Capon wrote it, it's here somewhere but I don't know exactly where, if he looks through recent spring threads he will find it

John


Hellfire - 5/1/09 at 08:37 PM

Just found it in this thread.

Phil


MikeCapon - 5/1/09 at 10:06 PM

Hi guys,

Here's the latest version. Any Q's pl just ask.

Cheers,

Mike


procomp - 6/1/09 at 08:11 AM

Hi

It all quite simple with it being such a popular setup on the original Locost frame.

For racing the usual setups will be .

Front from 300lb whith ARB to 400lb whith no ARB.
Rear virtually all run 120lb springs with 140lb MAX.

For road use .

Front 250lb to 300lb and rear is ussually a compromise depending on whether it's a regular two up or single driver but 140lb -150lb MAX

Only obvious thing thats apparent from the pics is that the front dampers are on upside down. Unfortunately despite what the manufacturers say GAZ AVO PROTECH do not run well upside down. The oil leaks past the seals during use and air enters the damper which gives all sorts of problems. Just refit the right way up.

Cheers Matt

[Edited on 6/1/09 by procomp]


beaver34 - 6/1/09 at 08:53 PM

quote:
Originally posted by procomp
Hi

It all quite simple with it being such a popular setup on the original Locost frame.

For racing the usual setups will be .

Front from 300lb whith ARB to 400lb whith no ARB.
Rear virtually all run 120lb springs with 140lb MAX.

For road use .

Front 250lb to 300lb and rear is ussually a compromise depending on whether it's a regular two up or single driver but 140lb -150lb MAX

Only obvious thing thats apparent from the pics is that the front dampers are on upside down. Unfortunately despite what the manufacturers say GAZ AVO PROTECH do not run well upside down. The oil leaks past the seals during use and air enters the damper which gives all sorts of problems. Just refit the right way up.

Cheers Matt

[Edited on 6/1/09 by procomp]


thank you for that, ill change them round when i take them off to make sure everthing is still o.k,