MM K member Geometry

[Boone]

There's been a lot of great stuff on suspension geometry going through our forum lately.

How does the Maximum Motorsports K member's altered hole pattern for the control arm (5/8" higher) effect the roll center, and what is the desired change in handling characteristics?

I assume MM is never going to come out with the SLA upper control arm they tease us with on their website.

My car is an '05 GT, and front suspension mods are a MM Sport Box (H&R Street Performance coilovers, MM c/c plates, Eibach front SB, MM bumpsteer kit). I know I need to educate myself further on this topic... so suggested reading is welcomed.

 

[Whiskey11]

There's been a lot of great stuff on suspension geometry going through our forum lately.

How does the Maximum Motorsports K member's altered hole pattern for the control arm (5/8" higher) effect the roll center, and what is the desired change in handling characteristics?

I assume MM is never going to come out with the SLA upper control arm they tease us with on their website.

My car is an '05 GT, and front suspension mods are a MM Sport Box (H&R Street Performance coilovers, MM c/c plates, Eibach front SB, MM bumpsteer kit). I know I need to educate myself further on this topic... so suggested reading is welcomed.

There are a number of very positive effects from raising the front RC by altering the LCA geometry up front.

Less body roll up front. The distance between the RC and the CG forms a lever. The shorter the arm the less roll there will be. If you look at the location of the front and rear roll centers you can get your roll axis which will tell you a lot about how the car's behavior will be while cornering.

Less body roll also means less camber loss while cornering due to the reduction in how far the control arm swings.

On that same vane is the camber curve changes too. This means you will gain negative camber quicker and will gain it longer before you start to lose it when the strut and the control arm are perpendicular to each other.

Possibility of %anti-dive changes. If all MM did was raise the control arm points equally on both the front and the rear this wouldn't have changed any, but if they changed it unequally you can gain or lose anti-dive. increasing it would mean there would be a reduction in brake dive at the possibility of "shocking" the front tires much in the same way %Anti-Squat can "shock" the rear tires (that'd be bad if the tires can't support it, good if it can).

 

[Norm Peterson]

There's been a lot of great stuff on suspension geometry going through our forum lately.

How does the Maximum Motorsports K member's altered hole pattern for the control arm (5/8" higher) effect the roll center, and what is the desired change in handling characteristics?

I assume MM is never going to come out with the SLA upper control arm they tease us with on their website.

My car is an '05 GT, and front suspension mods are a MM Sport Box (H&R Street Performance coilovers, MM c/c plates, Eibach front SB, MM bumpsteer kit). I know I need to educate myself further on this topic... so suggested reading is welcomed.

What Whiskey said., and it's particularly useful on a lowered car. Whether you're lowered or not, you'd almost certainly have to install and adjust a bumpsteer kit as a companion mod.


Norm

 

[Boone]

Less body roll up front.

So less of the body roll in the picture. That's a good thing. My left front was at -2.2* camber, and it's all gone thanks to the body roll. I believe the picture was taken in the off camber ~70 mph section of the "Stevie Wonders" on VIR North Course.

Does anyone have a SolidWorks model of the S197 suspension, or at least the locations of the stock attachment points orientation in space? I'd love to model the suspension so I really understand what's going on. I assume this is how the modification sickness begins.

 

[Boone]

OOPS. Picture.

 

[Norm Peterson]

Body roll is only part of the story behind the lost camber.


Norm