I just ordered a set of ohlins coilovers for my '03 evo. I chose custom spring rates 350 front/450 rear. I will be auto-crossing the car in ESP, and I also track the car. just curious what kind of spring rates others who track/autoX are running. I know that I could have gone stiffer (espedcially for auto-x) but I wanted to leave the car somewhat civilized for poor northeast roads. bear in mind i have not converted to front ltd slip so I went stiffer in the rear to try and maximize weight transfer there. i also have a cusco rear bar, trunk bar, and a rear strut bar. I am running 255/35-18 michelin PS2 on 18X9 rims. I will switch to R-compounds at some point this year....

 

when I get my GAB's they'll have a 12kg spring rate at all corners. My car is more of an autoX car then anything, so I dont mind going very stiff

 

The 350/450 will work well for the street, but for autocross you will still have plenty of body roll. I know what northeast roads are like, you can easily go up another 100 lbs on your spring rates and keep a decent street ride.

 

agreed, too soft

 

-If i go stiffer what sort of balance do i want to maintain front spring vs. rear? for example the stock front springs are approx 80% of the rears (180/225). my rates (350/450) are approx 78%.

 

The closer you can keep it to the stock ratio the better; adjust it up or down depending on your driving style.

I currently run at about 85%, but I might want to change that. your biggest issue is once you start going above 500lbs, you will have problems finding 10" springs that will fit. On the rears I switched to 8" springs, sacraficing some of the stroke of the rear strut, the front struts still use 10" springs. So far I have not bottomed out in the rear, but it's something you will have to deal with when running uber stiff spring rates.

IMHO, maintaining the stroke of the strut is important to the overall balence of the car. Maybe someone who can provide a better technical answer can chime in.

 

I'm currently running autocross in a 1900 lb car on 600/500 springs and it is handling very well. I had 392/280 on my 2700 lb Lancer and got terrible lean and outter tire wear (-2 camber up front, all I could get) on both track and autcross. So your 350/450 might be a bit soft considering the high CG of the car. Probably ok for track, but way too soft for autocross.