Lorax

I'm planning on lowering the crap out of my car with my new suspension and I was wondering if I'm going to run into issues.

I have newly rebuilt ball joints... but not the geometry correcting ones.

I'm running 500lbs in the front, and 600lb in the back. Will that be stiff enough to avoid destroying them?

Scootin159

If you're running 500 & 600# springs, you're obviously looking for performance. If that's the case, you'll actually get the best lateral grip with the control arms perfectly level with the ground, whatever ride height that may be. Otherwise you actually increase your roll center, and inconsistent camber (positive camber gain on inside tire, negative camber gain on outside tire, the opposite of what you want).

jf951

didn't someone kokeln?? make a product that allowed for lowering w/o the disadvantages?

Lorax

I went ahead and ordered some longer ball joint pins, I guess it's worth the money.

M758

Well,
I am not sold on the longer pins especially for track cars. Sure you improve the geometry, but the longer the pin the more load on the pin and pins can (and have) failed too. Feels like trading one problem for another.

anders44

longer 17mm pins are prone to brakeing, you will need 19 at least. charlie, racers edge, kokeln etc has them iirc

hp18racer

I've personally seen 5 lowered cars on stock a-arms break ball joints at the track.

Lorax

Well... soon it will be in my budget top buy some control arms, until then ill make sure my seatbelt is tight.

HansB

Sooner or later all lowered track cars with stock A-arms will break ball joints.

The very least you should do is use solid bushings, and inspect the play before every track day. Make sure the ball joint does not bind.

I always thought the longer pins are a scary solution

sawood12

Strange, there seems to be a very polarised view of the geometry correction kits out there. Before I installed my KW I wrote a note on this canvassing peoples opinions and experiences with these kits as I also thought the longer pins looked a bit scary. There were a good number of poeple who responded advocating that the extended pin kits are pretty good with a good safety record, which gave me a bit more confidence.

Also shortly after this a chap posted pictures of his car after a head on collision showing that the extended pin did not shear and break and it was the A-arm that broke before the pin.

I would be interested to know the circumstances around the cases of failed A-arms fitted with extended pins. Is is the same failure mode as failed A-arms without extended pins, i.e. over-rotation of the ball joint so the pin interferes with the ball joint socket rim?

PorscheDude1

Some interesting reading. A few track 968's had pin failures recently.
https://rennlist.com/forums/showthre...+joint+failure

Lorax

I found a good compromise. I'll just upgrade to longer 19mm pins. I think the extra meat should make up for the added leverage.

IanM

FYI - I used to run the Rennbay geometry correction balljoints. The control arm and tie rods will no longer move in the same plane, and the bumpsteer was ridiculous. I would only do this if you plan on extending your tie rod pins with a bumpsteer kit. My alignment guy had the car on his rack, set the camber/caster/toe, then showed me that by pulling the car down (compressing suspension) by only a 1/2", the toe changed by over 30 minutes. I pulled them out and went back to stock pins.

With that said, I do like the Rennbay balljoint pins, as the groove for the pinch bolt is a slot that does not extend all the way around the pin like with a stock pin. This maximizes pin strength in that critical spot where the pin narrows...where many people have had balljoint pins fail.

I would recommend the 19mm Rennbay balljoints in standard length.

Lorax

I just can't win it seems.

I hadn't thought about the bump steer issue. Where can I find extended tie rod pins?

daigo

I was worried about longer pins as well, so we incorporated a spacer that picks up on the shear load.