Real world first Gen F-body front suspension evaluation

[Beechy]

Originally Posted by Tinker

Am I going to be alright with 9 deg static caster that will near 12 degrees dynamic in a turn? I would hate to end up with a car that shakes like your local grocery store shopping cart.

My goal is to have a car that is fun to drive, reliable and safe to bring out to the track. I would love to be able to do 275's on all corners so tires could be rotated.

I thank anyone in advance for their constructive thoughts and advice.

Chris,
Shopping carts have zero caster, that's why they shake. Having more caster gets you away from that shake but in my experience/opinion 9* is too much in the wet. With reduced grip the tire can't deform enough to stay in full contact so lifts the outside wall (because geometry), you will experience massive push. More so with a wide, low profile tire. I have just gone from 8 to 6 for this reason.
Previously, from a stationary start, I could NEVER flick turn my daily........it would push straight forever. Also giving it gas at low speed around residential blocks (sharp turns) it just pushed.
Factory first gen geometry with upper arm drop and Global West rigid bushing/half height body mounts.....but like u say "geometry is geometry "

[Tinker]

Originally Posted by Beechy

With reduced grip the tire can't deform enough to stay in full contact so lifts the outside wall (because geometry), you will experience massive push. More so with a wide, low profile tire. I have just gone from 8 to 6 for this reason. "

Good info.
I imagine this will be the same effect depending on a 300tw, 200tw, or slick. Once I assemble everything I will check how much adjustment I have. Both the frame is slotted and the upper arms are slotted/slugged. Wouldn't be too bad to adjust upper arms depending on conditions or current use. As long as the wheels stay relatively centered in the wheel well for proper clearance.
Checking Temps across the front tires should be a good indicator.
Good notes of tire Temps with conditions should eventually get me where I need to be.

[SSLance]

Autocross in the rain with 9.x positive caster...

[Tinker]

Originally Posted by SSLance

Autocross in the rain with 9.x positive caster...

Attaboy Lance.
None too pushy when you went arse backwards.

[SSLance]

Originally Posted by Tinker

Attaboy Lance.
None too pushy when you went arse backwards.

That day was so much fun!

8 runs in the morning totally soaked, then 8 more runs in afternoon session on same course totally dry. One of my all time favorite autocross events.

[Tinker]

Thanks for all your input everyone.
I hopefully will stay at this now.

A quick shout out to Speedtech.
Got my frame today. Very nice piece. This will save me some cutting and necessary tweaking on my original frame to align everything and install the coilovers.
It's like I just finished weeks of work in one day!
I bolted the arms spindles and rack on...everything is coming out right where my measurements should be spot on.
Added shims on uca's to get my distance side to side and bam! 1/2-1 degree camber. Checked caster right at 9.5 degrees.
I will have some obstacles ahead putting in the Pontiac motor and attaching the tie rods to the steering arms, but this is the most progress in many years.
Thanks again. I hope to continue updates in my build thread.

[rickpaw]

So, it looks like you were able to use the arms/spindles on the Speedtech frame?