Interesting thread

[gareth h]

I've been messing around with my suspension set up for a couple of years, and always thought front engined, rwd cars ran with stiffer springs on front.
Came across this on the LS1 forum.
http://www.ls1gto.com/forums/showthread.php?t=2715...

[MyM8V8]

gareth h said:

I've been messing around with my suspension set up for a couple of years, and always thought front engined, rwd cars ran with stiffer springs on front.
Came across this on the LS1 forum.
http://www.ls1gto.com/forums/showthread.php?t=2715...

It all depends on a number of variables.

Generally speaking for maximum bite/grip, you want the softest springs possible, but this could cause lots of roll in cornering. That's why you have an anti roll bar connecting one wheel to another to overcome this weight transfer in the corners. It's a complicated set of permutations, because of geometry and the laws of physics.

There is no one size fits all in suspension tuning, and not many people pay attention to this area because they are too busy building big horsepower. You must choose a spring/shock/roll bar combination to suit your vehicle weight, geometry and application.
It's to do with roll centres, motion ratios, wheel rate, weight distribution/transfer, squat, oh my goodness this could be a long one, etc etc

This is why its possible to have softer springs on the front than in the rear.


Hope this makes sense?

Edited by MyM8V8 on Sunday 12th October 14:25

[stevieturbo]

gareth h said:

I've been messing around with my suspension set up for a couple of years, and always thought front engined, rwd cars ran with stiffer springs on front.
Came across this on the LS1 forum.
http://www.ls1gto.com/forums/showthread.php?t=2715...

The spring pressure seen at the wheel, WILL be higher.

trailing arm assembleys have leverage applied to the spring, where as McPherson struts have virtually none, being situated right at the wheel.

Hence the actual springs may have quite different spring rates front and rear, but thats not to say the wheel sees the same.

[MyM8V8]

stevieturbo said:

gareth h said:

I've been messing around with my suspension set up for a couple of years, and always thought front engined, rwd cars ran with stiffer springs on front.
Came across this on the LS1 forum.
http://www.ls1gto.com/forums/showthread.php?t=2715...

The spring pressure seen at the wheel, WILL be higher.

trailing arm assembleys have leverage applied to the spring, where as McPherson struts have virtually none, being situated right at the wheel.

Hence the actual springs may have quite different spring rates front and rear, but thats not to say the wheel sees the same.

That's a better way of putting it, sorry to have been too technical sounding.

"Hence the actual springs may have quite different spring rates front and rear, but thats not to say the wheel sees the same." = wheel rate.

Edited by MyM8V8 on Sunday 12th October 17:06

[gareth h]

Thanks guys, I hadn't really considered leverage on the springs. The handling has been transformed by changing from 19" rims to 18" and softening the springs.
I'm now running the same spring rates front and rear so wondered whether I should have left the rear with a higher rate.

[Magic919]

If you are running the same spring rate both ends then the _effective_ spring rate at the rear is inherently 50% higher.

[MyM8V8]

gareth h said:

Thanks guys, I hadn't really considered leverage on the springs. The handling has been transformed by changing from 19" rims to 18" and softening the springs.
I'm now running the same spring rates front and rear so wondered whether I should have left the rear with a higher rate.

Out of interest what are the springs rated at?

I'll have to get my books out and get you the formula for you to work out your wheel rates, or just do a google search. The yanks have it all on various sites.

Edited by MyM8V8 on Sunday 12th October 22:09