Ground scraping ball joint front end / Options

[dd-ardvark]

All right ball joint front end fans, I posted this question over of germanlook.com and got a shallow response, so make me proud to know that you back yard joes
know your stuff.
I want to sit the front beam on the ground, another words I want to hold 2-4" of ground height and still have a suspension with a 25" dia. tire.

The problem that some of you probably have found, the ball joints bind at about 3" from ground scraping. Although using the lowered ball joints helps,
it's still not on the ground with this sized tire.

The car's an old CMC speedster kit car on a IRS balljoint chassis, the ball joint spindles have been cut off and combo spindles are welded in place, dropped by 2.5".
I'm using Tatum Motor sports aluminum hubs and as much as bending the trailing arms in to give more negative camber, I've already bent them in 0.5" also.

This is my question to you: Have any of you tried bending DOWN the last 4" of the upper and lower trailing arms by 1" to level out the ball joint in the trailing arms,
thus allowing the drop of the front end by an additional 3 to 4" before the BJ's bind
This looks like it might be the ANSWER to getting the BJ front suspenion
on the ground.

Your thoughts, please.

[FJCamper]

Hi Ardvark,

Are you doing this with the intention to improve handling?

I appreciate the front end work that's gone into your Speedster there. I'm trying to find a place to start to see if I can give you a sensible answer.

FJC

[reefskinner]

My 66 will set the beam on the ground with a 24" tall tire. I am running dropped spindles and the long travel ball joints. My adjusters are welded in so the "open flat portion" is tilted 5° back from vertical, so even when adjusted fully up it sits quite low.

[dd-ardvark]

Hello FJC, to your question with regards to improving the handling by lowering the car:
Yes, is the answer.
Also my intent is to hold a riding height that of a soup can rolled under her (2"-3").
The car sets on the BJ's right now, and tomorrow / Sunday I may find the time to bend the trailing
arms..., I'll let you know how it goes. I've got another set If I find this isn't the route to take.

As far as to much info in the drawing..., I know it's a lot to bite off in just one look.
This was my working drawing that I've used to build this car with. Most..., of what you see is
now constructed and this drawing has been revised to reflect the state it's in now.
It's obviously not finished, but getting their.

Since I'm still in the fitment stages, do you or any of your racing buddies have any experience
with the over the top swaybar style by Whiteline.
I'm looking at the 7/8" over the top, narrowed bar. www.aircooled.net, Part No.SSS0002.

[Marc]

...Have any of you tried bending DOWN the last 4" of the upper and lower trailing arms by 1" to level out the ball joint in the trailing arms, thus allowing the drop of the front end by an additional 3 to 4" before the BJ's bind ...

Personally, no. But I know of at least one street stock circletrack racer who was doing this ~25 years ago (there's not much new under the sun). Seemed to have worked out OK, but I can't offer any details on the process - I assume they had to heat the arms before they could be bent in that dimension, if you're going to do that with the balljoints installed have lots of wet rags/water handy to keep from melting them. I'd make a jig (nothing fancy, just some 2x4 scraps notched out to serve as V-blocks) to make it easier to gauge your progress.

A front end lowered this far will always be stiff riding. With the stock control arm angles, the spindles swing back slightly as the suspension compresses. With the arms angled upwards, the wheel actually needs to move forward - against the direction of travel - as the suspension compresses, and that tends to put things in a bind. And with the steering box in the stock location bumpsteer is objectionable (inverting the outer tierod ends will help some).

Would it be feasible with your bodywork to mount the entire beam assembly higher on the pan? That'd give the stance you're after while still retaining some semblance of a functional suspension.

[FJCamper]

Above: Whiteline's shackle problems, and our end link mods.

Hi Ardvark,

The Whiteline bar is a good one. It is very similiar to the Porsche 356 arrangement in the end link configuration, because it comes from the top down.

Be aware that the good thing about this bar is it's adjustability. The bad thing about it is the end links are servicable but crude, and the bar itself is very stiff even in it's softest setting. A nonadjustable 19mm front bar gives you close to the right amount of roll control for our sort of axle roll center and low-mass vehicle weight.

We used a Whiteline 22mm adjustable rear bar and had to completely fabricate our own end links. 22mm is okay for a bus, but way too much for a Ghia. Even the 911S's came from the factory with less than 19mm rear bars!

Anyway, the faster we became, the less rear bar we needed, and shifted handling tuning to shock settings (we use Koni adjustables) and tire pressures.

The reason we didn't/don't use the Whiteline front bar is it prevents us from using our tow bar. If the towbar were no issue, I'd use the Whiteline.

FJC