I'm using a custom MX-5-based suspension. I moved the top arm back 1/2" to provide for additional castor. This now makes the damper angles wierd.

I'm using a bike damper as a mockup because it is the exact height that my real damper (yet to arrive) at rest. Check out the angles I need to use.

I've looked through many build diaries and everyone's damper bracket seems to be parallel with the suspension pickup bolts. The book too shows the damper bracket centered on the lower arm and parallel to the suspension pickup bolts.

I have more pics of what I'm talking about in my archive. I'd love to get this resolved so I can move forward with the W/E build.

--Thanks, Chris

[Edited on 16/10/04 by chrisf]

[Edited on 16/10/04 by chrisf]
Rescued attachment Pic1.jpg

If the dampers have rod-end bearings either end, it wont make any difference, in fact, arguably, it could be slightly better geometry wise.

However, dampers with bushed ends might not be so happy. They will be trying to 'twist' the bush as the dampers move in/out. They *should* cope with it, but that is the only real downfall that I can see...

Ideally the damper should be aligned so it is inline. If it is offset slightly you will put a bending load into the damper, this will increase friction and shorten seal life, both theoretically bad.

However as with nearly all aspects of car building it is all about compromises. If the offset mounting gives better packaging it may be compromise you are willing to live with.

If you can mount it inline.

JB

Thanks for the responses. Whould there be any adverse effects of offsetting the damper pickup? Right now, it is inline with the ball joint. I could move the pickup rearward and this would straighten everthing up. My concern is that I would put much more bending load on the rearward control arm. Is this bad news?

In your archive are a few mock-ups of your ideas for inboard dampers in 3D models. If you were to use these then you will probably loose these problems. Is there a reason why you haven't opted for this idea. IMO it would be a very nice way of doing the front suspension.

Andy

In inboard idea was really cool. It took me quite a while to design. It had a very nice progressive design. But alas: the tolerances were very tight. I could never make it work. Either the steering shaft was in the way or things would bang into each other. I could have forced it to work but I would have never been happy with the results.

After 4 months, I finally tossed in the towel. I still have the inboard rear suspension.

If the upper damper bracket was mounted under the tube rather than on the side, it would give you more clearance between the spring and the wishbone. This should certainly give you more scope to mount the damper "straight", although it will reduce the effactive spring rate slightly as the damper will be working at a larger angle.

If you want the bracket on the side, then the holes in the bracket should be inline with the wishbone bracket or the damper bushes wil have a shrt life. Either make a custom bracket with one side longer than the other, or space a standard bracket out at one end.

[Edited on 17/10/04 by MikeRJ]