Koni Adjustable Shocks & Struts Follow-up

[rice eater]

cool, That is very good info to have. I know of 2 or 3 guys that race at our scca events and claim to be at 3 deg. negative camber. But they are all in sm. Do you know what I can do being in Sm?

[scottherbert]

Originally Posted by rice eater

cool, That is very good info to have. I know of 2 or 3 guys that race at our scca events and claim to be at 3 deg. negative camber. But they are all in sm. Do you know what I can do being in Sm?

I have the SCCA 2007 Solo Rules in my hand and I can find nothing specifying how much negative you can run. I've been told 2 degrees negative max in Stock Category and up to 3 degrees of negative in other categories, but I'll be darned if I can find those specifications anywhere in the rules.

So I've asked the question on the Rocky Mountain Division tech website and I expect one of the SCCA Scrutineers will answer -- and that answer will definitely be the final answer. As soon as I get an answer, I'll pass it along. I'm interested myself -- if I can run 2.5 or 3 degrees of negative, I'll do it! Hoosier says that their slicks need 3-6 degrees of negative to work best, but that 2.5 degrees is acceptable if you're concerned about excessive tire wear.

I was looking at the Factory repair manual for our struts and I've come to the conclusion that there will be no easy way to change rebound adjustment on a cartridge in a Redline once mounted. Since there is a top-cap bolted onto the upper spring plate, and the top cap has it's own bolt up through the strut tower, it will be almost impossible to change rebound settings without disassembling the spring. On the other hand, even with the Quaife (which I have), I can (and do) easily lift the inside front high enough in a hard turn to still spin it (no torque load on the Quaife works the same as an 'open' differential) -- even though I'm 7000" above sea level and getting about 20-25% less horsepower than you have at sea level. Which means that you'd want to use the lowest possible rebound settings anyway -- so no problem, set it and leave it. The biggest gain from Koni strut cartridges would be the higher compression.

By the way, on the GM build for the racing Cobalt SS, they remove the front swaybar entirely -- which I assume is to help keep the inside front tire on the ground during cornering. Granted, they have coil-overs, camber plates, custom bilsteins, completely revamped front suspension geometry, blah, blah, blah... But I think the same general principals apply. When I get the guts (and the time), I'm going to remove the front swaybar and see how it handles. Who knows, it might be the fastest way to run.

Seat-of-the-pants, the car feels much more stable in hard cornering with the Konis on the rear. It just feels more solid and predictable, and I've pushed it hard the past couple of days...

Scott

[superbird]

pm me your number

[rice eater]

bump Have you had any word from koni yet?

[scottherbert]

Originally Posted by rice eater

bump Have you had any word from koni yet?

None yet. And I haven't forgotten. And I'm about to ping my contact again tomorrow. He was supposed to have gotten back off the road last Wednesday.

About the camber, according to the SCCA crowd (Solo II Chair for the region among others) there is no limit to the negative camber. I was sure I had heard -2 for stock and -3 for other, but I was wrong.

Scott

[rice eater]

cool, I have some grinding to do then.lol

[scottherbert]

My Koni contact replied to my last email and sent me a shipping address. He says he's going to be in the office for the next several weeks, so I hope he'll have an engineer get on it right away. He indicates that they plan to try using the cartridge developed for the Cobalt SS in the struts (probably the best choice because it's already valved for a very similar vehicle.

I plan to ship the struts this weekend.

Scott

[scottherbert]

Originally Posted by rice eater

cool, I have some grinding to do then.lol

According to the Ion factory repair manual, you should "file" out to the edge of the "stamped ring" around the lower knuckle bolt hole. If you look really closely, you can see the "stamped ring". I'm pretty sure that you can get more than -3 degree just by filing (grinding/drilling) out to the edge of the "stamped ring".

Scott

[rice eater]

cool, I will be working on her weds when my head gets back from the machine shop. I will add that in on list of things to try to her.

[scottherbert]

They should be at KONI this Friday.

BTW, let me say it again, the handling difference -- just with the rear adjustables -- is very apparent -- MUCH more stable!

Scott