I am looking to buy Koni shocks and ground control sleeves. I also have camber plates and will be running around 2° of camber in the front and about 1.5” drop.

This will be primarily an Autocross car, but it will be driven on the street occasionally.

What spring rates do you recommend for the Konis?

My roommate has KYB AGX’s with 370-245lb/in (front-rear) and I could defiantly handle a tighter spring. However, his car feels like it has a slight oscillation over bumps which leads me to believe there is not enough dampening (the the AGX’s set to max). I don’t want to spring that is too tight for me shocks.


Thanks,
Jason

 

The Konis will handle up to 600# rates in the front.

 

Excellent. That is good to know. Where did you get that information though? (Just curious)

…and do the AGX’s have a “maximum recommended spring rate”?

 

I wouldn't go more than 450 - 400 in-lbs. in the front and 400 - 350 in-lbs. in the rears on the KYB AGX's.


-Ted

 

Re the 600#, directly from Koni NA, shock tech man Mike. I run 500# in my ITS SCCA car and was interested in upping them and he said to 600 I would be fine.

 

I ran the K2RD coilover kit with AGX's and Paul said the max spring rate would be around 400# before the strut itself couldn't handle it reliably and could lead to failure. I was also told that Konis can handle a much stiffer spring. I ran 400# and 275# which was very stiff on the street with the struts on the softest setting and the rears 2 clicks away from softest. I did some roadracing and found when setting the AGX's to full stiff the spring setup was awesome. I wouldn't have changed a think aside from wanting more power from my n/a S4.

If this is a street car in any form... I wouldn't go any stiffer than that. I have a high tolerance for tradeoffs to make my car better.... that may affect comfort. If you do not... I wouldn't go0 any stiffer. Mine was nearly unbearable on bad sections of road as here in San Francisco smooth road isn't found very easily.

I mainly purchased the AGX's as they were $355 on special at the time.... Had they have been more I probably would've bought Koni's.

Spend the money on good tires.... I don't think the crazy stiff spring rates will make that much of a difference (meaning 600#...). AutoX has a lot to do with driver skill.... so go to more events and hone your skills.

I have a set of TSW Hockenheim with 235/40/17 Toyo shaved RA1's for sale. No spacers needed when used with coilovers. They grip awesome.

-Mark