Enchanced cornering from rear coilover angle ?

[ripdog28]

I am debating if i should swap over to a coilover in the rear and was thinking that i could enhance the cornering by angeling the coilover inward at the top. Say about 15 to 20 degrees. I would fab a bracket from the rear of the trailing arm and make a new upper bracket.

Q1, anyone think this would help handeling?
Q2, anyone tried this?

[LONGHAIR]

Whenever you angle a shock from the direction of wheel travel you are hurting it's performance. There are "practical" issues involved as far as fitment though.
Doing so with a coil-over, which is your suspension not just the shock, would probably make body roll worse. You are essentially narrowing the width of the upper platform. You would get more movement from the body with less actual movement of the spring that way.
I would go for as wide and vertical as is reasonably possible.

[ripdog28]

AAAAHHHHHHHHHHH. So the angled coilovers on race cars are because their chassis is so low and not frame rails like ours...

[nuke1]

If you want to go full road race, ie pro touring, then angle your shocks in a 30 degrees, that is the max to lean them in. I have mine set at 25 degrees. However if you want to juat drive angle in 5 to 10 degrees. the more you lean a coilover then you have to figure out your new spring rate because it decreases as you angle it in. Angling the shocks or coilovers, affects your corning, increasing you ability to turn into the corner harder as the shock pushes against the corner unlike if it ws strait up and down.

[chevy_mike]

One of my chassis books explains the relation of shock or coilover angles. As they are leaned over, the actual damping/spring rate changes. The more leaned over they are, the less the rates become. You can compensate with stiffer valving or spring rates but you will reach a point of no return.

In an ideal world, the most linear is to have them 90* to the axle as you will get true 100% rates from them. Packaging is hard to do this way so you start leaning them over. It is not proportionate to the lean, so 15% lean over does not equate to 15% loss of rate. I don't recall the forumla off the top of my head.

I would suggest you pick up some race car chassis/suspension books and do some reading before just doing something.

Good luck.

[LONGHAIR]

Originally Posted by nuke1

Angling the shocks or coilovers, affects your corning, increasing you ability to turn into the corner harder as the shock pushes against the corner unlike if it ws strait up and down.

I would have to see concrete proof of that one....

The springs/shocks just hold the vehicle "up", as in "suspension". Sway bars are there to help with body roll and some type of "centering" device keeps the axle under the vehicle.
An angled shock/spring has no more ability to push against the outward (centrifual) force of a turn than a vertical shock/spring. I would even bet that it is worse because the upper mount is closer to center. Not only has it lost some of it's spring-rate, it would put a bigger load against the swaybar to combat the bodyroll.

[leftcoast66]

I just pulled out the Herb Adams suspension book and its got a diagram showing at 0 angle its 100% effective, 10degrees 98% effective, 30degrees its 86% effective and 45 degrees its 70% effective. So based off of this I would go with placing it vertical. yeah you can angle them, but then you've gotta mess w/ more equations and more to worry about rather than putting them straight and having it be simple.