Double wishbones on drive wheels without much space?

[mtv dave]

I've been trying to work out how to mount the spring and damper on the drive wheels (mid-engine, RWD). Mounting them inboard isn't an option as the space available is too small. I could offset the shock', but I'm thinking it would induce torque that'd be hard to model and handle on the wheel.

Currently I'm thinking that mounting it between the joints of the top and bottom wishbone, with a cam to the top wishbone acting as a pushrod, but I'm not happy about the extra force it will put on the chassis in a region I'd like to stress anymore than absolubtly necessary.

Does anybody have any ideas?

[wilsongt]

Hi, if you can't go inboard in a lateral direction, because the engine is in the way, how about going longitudingly? eg pull road down to the level of the lower wishbone, acting on a rocker that turns the motion 90 degrees to a horizontal damper running in teh fore/adft direction, in front of the lower wishbone mountings. or go for a push rod and do likewise at a higher level

Both have been done before, so work

Regards,
Glenn

[trackcar]

When you say induced torque from an offset damper do you mean it will impart a torque reaction on the hub because of it's non-central location on the upright? I can't work out what you're referring to .. maybe send a piccie to show us your space limitations?

[mtv dave]

trackcar said:

When you say induced torque from an offset damper do you mean it will impart a torque reaction on the hub because of it's non-central location on the upright? I can't work out what you're referring to .. maybe send a piccie to show us your space limitations?

Yeah - the point on action on the hub will not be central - it would be slightly fore or aft. I've since seen that's how it works on the Elise, so it probably wouldn't be as bad as I was expecting.

I'll start looking into the mechanics behind push/pull rods - I'm still not sure how to twist the rotation axis without things getting complicated fast.

Edit - It's all in CAD at the moment, but I'll try to take a decent screen shot and host it somewhere to show what I mean.

Edited by mtv dave on Thursday 24th August 09:42