Kirkham 427 chassis : Ground alignment

[Stephan427SC]

Hi guys, can someone tell me which gound alignment/setting the upper and lower a-arms have when car comes from factory ? Means how many turns are the balls joints out from full closed to get the ground alignment / axle width of the car ? Any help would be fine.
Thanks, Stephan

[Stephan427SC]

Those are the A-arms....

[Stephan427SC]

sorry...here are the a-arms

[Anthony]

I would say email Kirkham, that way, you can print out their response instead of trying to take notes or use your memory ( i don't have one anymore).

If you do this, please send me a copy of their response.

[FatBoy]

You can't set the suspension geometry based on number of turns. I have the recommended geometry settings from KMS somewhere, which I will post when I find them. However, I would recommend having the geometry properly setup by a specialist. The difference in road behaviour between a competent DIY job and a professional specialist is astonishing.

Paul

[Ron61]

I agree with Paul. I tried that once and it didn't come out to bad but still didn't seem just right so I took it to a specialist and the difference was amazing.

Ron

[Anthony]

The final settings regarding toe in, caster, camber, are out there, but I was wondering where do you start, at what settings regarding the control arm ball joints, etc. I just want to double check my car to make sure the adjustment is within reasonable settings, i.e. the adustment is not at or exceeding what is reasonable. I didn;t set my car up originally, and I just want to make sure someone didn;t adjust it more than it should have been.

[FatBoy]

I don’t really understand what you mean by “adjusted more than it should have been”. You adjust it until it’s right, no more, no less.
On the front, the lower arms aren’t adjustable, so they’re your fixed starting points. You the adjust the upper arms to get the correct camber and castor, followed by the steering arms for the toe.
The rear is a bit more complicated because of the adjustable trailing link. The problem is that you can adjust the upper arms at both ends and adjusting the inner joints independently will affect rear bump steer as well as camber. I found that I ran out of adjustment and had to get some modified top-hat spacers for the inner joints to move them forward in the chassis.
This will all be bread and butter for someone who knows what they’re doing. If you can assist your chosen expert, you will learn a huge amount about chassis and suspension setup.
One world of advice; don’t be tempted to say “it’s close enough”. Keep going until you get it as close as you possibly can. The time and effort spent will reward you out on the road.

Paul

[FatBoy]

I’ve just realised what you meant and we’re talking specifically about the upper rears. From memory, I didn’t have that issue, because the outer ends had to be screwed right in and the inner ends were close to fully in.
If you find that when everything is properly setup, you have markedly different amounts of thread showing at both ends, you could adjust them by an equal number of turns to even them up. But re-check your measurements again afterwards.

[Anthony]

Well, my cars came "set up" from the dealers. The alignment on the one wasn't even close, the other one not bad, and one lock nut was loose. I aligned my cars myself, and what a difference ! With all the other stuff that wasn't assembled or installed correctly, it makes me wonder now again about the chassis assembly, and i was wondering about how many threads should be showing, as I'm not sure it the adjustments are at the limit, or even past it. I need to look under my cars and assess it.

thanks.