Dallas J

iTrader: (1)

Oh wow never heard of them but here they are,

http://www.ludicrousspeedshop.com/Featured.html

IMO, so many lost opportunities for improvements. They might even be lighter than mine but without working on roll center or bump steer fixes the benefits aren't huge.

RJones

iTrader: (5)

So uhh... you've got me down for a set right?

Balrok

iTrader: (15)

Yay parts Did you get the total weight savings? I assume this is still just the two fronts.

Dallas J

iTrader: (1)

You know it



Ill have to double check weights after this final version is done but I think we're right around 5lbs lighter now each side. Added a little weight back on this latest version just increasing stiffness and strength, especially through the steering system. I widened the bolt mounting points and changed to M10s from M8s along with the greater bump steer adjustment on the burly arms. Ackerman remains stock unless someone really wants something different.


I don't see how/why the "other" designs out there get away with weak looking steering mounts. Beyond just the actual strength of surviving steering forces there's also being stiff enough to not be a soft spring in the system. It is just a cantilevered bar after all connecting to the wheel bearing through a torsion bar.

nollij

iTrader: (21)

Have you considered making the LCA connection point to the knuckle adjustable so you can adjust caster and move the wheel around in the wheel well?

edit: I guess that would require some way to adjust the length of the toe connection point as well.

Dallas J

iTrader: (1)

There would be so many unnecessary sacrifices to make something like that work and the granularity in adjustment would be far too coarse. Considering the forces in an upright, it really needs to stay solid as much as possible in the core locations of load path which is basically steering to hub and ball joint to hub.


Would be much better to have that adjustment in the control arm itself which actually becomes a little tricky. How do you keep rod ends out of bending without creating a length change between the inner mounts when adjusting. Only thing I can think of is to either make them two piece and pivot at the connection point between two pieces have a portion of the load on the rear joint in bending. The latter also has clearance issues with the chassis right there.


These are just things Ive been noodling on for my next project. I really want adjustable control arms. Welded tubes is the easy path, but I have a CNC...

griceiv

iTrader: (2)

do it like this...


but don't use rodends on the inboard of the main link, use shims to adjust a bearing holder like they do on GT3's.

Dallas J

iTrader: (1)

Nice, I like that idea for inboard of the main body.

nollij

iTrader: (21)

That is a wonderful design. How do the shims work? Is there a diagram?

griceiv

iTrader: (2)

I'm not even sure a camber adjustment is really required, could easily make the arm lighter without it.

i think this picture should explain everything.

Dave W.

Since you're looking at Porsche 911 parts, and you have a CNC, here's a few good examples to ponder;
http://elephantracing.com/suspension...ntrol-arms.htm
Basically, convert the front control arm into a two piece assembly.

griceiv

iTrader: (2)

threads in bending...would not buy.

LetsGetThisDone

iTrader: (1)

Pretty standard for control arms to have heim joints with thread in bending like that. As long as the part is big enough, it's not an issue.

ViciousLSD

iTrader: (2)

Well I'm finally going to the national championships, just in time before I get too old.
I just have the standard bolt ons. I did finally got around to work on a tire trailer and 'quick release' hitch/receiver I lowered the trailer too









I hope to make it coming from houston, having never driven more than 5hrs.
looking forward to meeting all you autox addicts!

Dallas J

iTrader: (1)

Rad setup! Car also seems way to clean to be an SM car. Good luck out there!