I have just recently lowered my car, but have the same problem currently. I have been told this can be fixed though... I just need time to have the car on jacks, and adjust them. I'lll let you know how it comes out.
No luck yet... next meet we have (socalkiatuners.com) we are going to try to figure something out... I got them from kfxperformance.com (if you end up ordering some, mention that haddy from SoCalKiaTuners sent ya!), here are some pics of the drop http://socalkiatuners.com/10_29_05.htm (beige spectra).
my 2004 Cerato/spectra ex sedan is sitting on 17inch Falken 205 / 45ZR tyres.
Ive recently lowered it by 2 1/2 inches.
Here in aust they didnt have lowering springs for this type of vehicle so they resetted the stock springs by 2 1/2 inches lower.
like you i too dreaded bump stops as it occur with every bump however small or big with my previous car with 15inch wheels and that wasnt at all lowered! :lol:
so the outcome of a lowered Cerato - absolutely perfect!
Not only did it enchance the look of my ride, but the i get no bump stops at all. the ride is suprisngly the same as it was when it wasnt lowered. It was still quite smooth and comfortable. You qill feel that your closer to the ground, but then u will feel that the aerodynamics of the cerato is improved. Body roll is still there, but i'd said for stock suspension and it being lowered, body roll was halfed then what it use to be. imagine with sports suspension! and sway bars!! omg! haha
I tested my vechicle one day with a full load of 5 young adults. weight average of at least 50 - 60kilos each.
no problems at all. just have to drive really slow and i mean really slow over speed humps or ditches in the road.
so i guess.. resetting stock springs would be a better option than installing new springs, as the suspension is fine tuned with the stock springs, installing new ones could in my opinion cause problems.... and maybe the type of tires i have contributes in preventing any bump stops.