I think youre going to find a lot more understeer than youd like with 550# FRT and 250#RR springs.

I would imagine youll be picking up some much stiffer rear springs in the very near future, those rates even though higher(especially in front) dont differ drastically from the basic front/rear ratio used by many of the over the counter coilovers.

550 is a LOT of front spring, Koni Challenge cars run aorund 600#, Youve got a lot of tire maybe itll work Best of luck at your comps!!!!! If I ever get my car done with these little 245s and I make out to Rockies, we"ll have to go at it.

 

Thanks for the update. Looking forward to hearing more. You must have a really still rear bar for a 250# spring.

 

I expect a lot of understeer -- but with a 22mm add-on rear bar and some tire pressure mods, 3-4 degrees of negative camber up front, I'm not sure how much. The best news is that with the new GC rear springs I can get any rear spring rate pretty easily -- no pig tail on top. I'm looking at some 8" Hyper coils in the 700 lb range.

My fellow competitors -- the guy who've been winning at the Nationals in BSP, CSP, DSP, FSP, with FWD, RWD and AWD cars -- are all recommending F600/R700 as a start point. Some are successfully running fronts as high 750 and rears as high as 1000 (a Honda Civic runs the 1000lb rears). And most run almost no rear sway -- or it's very soft -- so the suggestion from them is to remove the Progress sway and figure out a way to soften the stock bar (I think that's too difficult/costly).

Part of my problem is that I can't afford to trailer the car, I have to drive there, hauling a tire trailer with 4 slicks and 4 rains, so I'll probably have to drive with a stick between my teeth to keep from chipping them on the trip -- it should be very, very rough driving.

I look forware to more Cobalts participating. You'd think there'd be lots already, but I haven't seen too many.

Scott

 

Follow-up...

I've installed the rears and I'm convinced that the 8" rear springs are almost too long -- I'm seeing about 1" (perhaps 1.5") of total drop with the rear adjusters at the bottom -- I'd bet that I could use 6" rear springs just as well. I'm going to first try pounding the Ground Control threaded sections down even more over the bottom section but I doubt that I'll see more than 1/8-1/4" more drop (the lower screw-set is a little off the bottom of the lower mounts. I think I'm going to see how 6" springs work. I think I could move the adjuster up near the top of the reach and 6" springs will fit -- I guess I'll have to see.

I measure 27" (perhaps a bit less) from the ground to the lower edge of the rear fender. I'd really like to see about 25.5" to 26" with racing rubber.

I could see where 6" springs might be a problem on a street car -- bounce up high and the springs come out -- but I don't think they'd be a problem on a track car. Any thoughts?

I suppose I could drive to the car to the site with 8" springs in place and then jack it up and go with 6" springs on site... Not the ideal but it would work.

Scott

 

If you run 6" springs youll need to run helper springs to keep em from popping at under droop.

 

get a real rear bar run 450 front and rear and a 1.0 0r 1.25 (tight auto x) and you will be qwiker. Just because the honda craizies run 1000 rear dont make it right. you need wheel travel and compliance to work the tire right. too stiff and you work the car too much...just my .02 and btw hoosier a6 way better tire for auto x

 

I've decided on 7" 650lb springs (Eibachs for these -- I didn't see any Hypercoils in 7x650). I'll see how they fit and run -- this is strictly a start-point... I'm pretty sure 7"ers will work for my needs, but we'll see. I ordered them through Summit Racing but Summit's indicating that they might not be able to delilver before I head off for the Nationals on Sep 6th -- I'm hoping but no guarantees. If I get these in, I'll probably remove the Progress add-on swaybar entirely -- but, again, we'll see. I just don't know how it will handle til I try. It isn't too difficult to change the 8" springs for 7" springs, so I might switch when I get to Lincoln airport -- it's about an 8 hour drive hauling a tire trailer.

From *redline: I agree, Hoosiers are better, but I only had a set of Hoosier 255s (vs the Kunho 285s) until about two days ago and I had to see if 285s would work (they do) -- so I've ordered a new set of Hoosier A6s in 285/30 x 18 (this is killing my wallet). I'm planning to run sticker Hoosiers at the Nationals (not that it will probably really make a difference -- I'm still sorting everything out -- but there's always hope). I looked at the Hoosier A6 in 295/30s -- last year's natl champ BMW is running 295s -- but found they're actually 0.1" narrower than the 285s and 0.5" taller -- which probably wouldn't be a problem 'if' I had a little more torque, but there's no guarantee I'll get the Stage 1 installed before Sep 6th. I should add that the BMW has much wider rims.

Scott

 

contact Josh and put the 1.0 or1.25 bar on from OTTP I guarantee you will be quicker. if the courses are tight the `1.25 i am running that at the glen next week

 

Has anybody tried Pedders? I heard good things about their springs being the only ones that drop while improving handling too. It looks like they sell coilovers too.

 

yup...lol

 

Ive been on Pedders springs since March, absolutely f*ckin love em.

Coilovers, nice stuff but I see nothing super special about them, Id love to be wrong though.

 

What kind of drop would I be looking at?

 

more than proKit but less than Sportlines.

Looks like this on 245/40/18s

 

We use are own ARK springs for our dampers. Different dampers have different compression rate, therefore it will only be fitting to use a damper that is compatible with the springs.

As for the 32 way adjustable, I challenge you to drive it with maximun setting and then set it to the minimum settings. you will see that there is very little to no difference. We know this due to the tests we have ran. Also the longevity of the dampers is important. We have research our dampers in all these categories and have proven our performance on street and track.

Note: stiffer is not always better

 

I want to thank everybody for their input -- particularly Maven and Qwikredline for their knowledge and experience -- and the vendors who chimed-in (ARK...). The information and the perspectives are invaluable.

Now I have to take your inputs, along with that of the 5-6 SCCA Autocross champions I've been corresponding and talking with, and put it all into practice. As I mentioned earlier, I'm shooting for next year's Nationals to have my ducks in better order -- this year's just for the experience.

For now, I'm looking to run 2.5 ID x 6" x 550 lb fronts and 2.5 ID x 7" x 650 lb rears with nothing but the stock swaybars (I've had very different opinions about spring/swaybar combinations from both the Cobalt and the SCCA sides -- I'll remove the 22 mm Progress bar). And I'm not sure I'll get the 650s in time for the Nationals.

I have a set of camber plates from B&G (that I had to adapt to mount with my Koni struts - I drilled and tapped the top bolts to work with the 14mm x 1.5 Koni bolts -- they work great!) and I suspect, just from looking, the I could get more than 6 degrees of negative camber at the limits.

I've ordered a new set of 285/30 x 18 Hoosiers and should have them mounted by next week (my Kumhos are about shot - so I'll run the Hoosiers for one autocross before the Nationals).

I discovered that the Ground Control front adapters don't want to fit over the Koni cartridges, the ridge on the top of the cartridges is just too big -- so I removed the cartridges, installed the Ground Control parts, and re-installed the Koni cartridges with the Koni rubber shock covers and they work GREAT! the Koni ridge is almost a perfect press-fit over the Ground Control screw adapters!

So now all I have to do is out-drive a couple of national champions, assume that my first shot at a solid setup is what's going to work best (NOT!), and get lucky... There are 62 local SCCA competitors from the Colorado region competing in the Nationals -- including 4 other local DSP drivers (who have all been faster than me).

Again, Thanks for all the help!

Scott

 

good luck, good racing!