Alignment settings for 19" wheels frt/rear

[Projectguy35]

I knew my car would handle different when I fitted the 19" wheels/tires, but I didn't know the responsiveness was going to drop to Cadillac STS levels. I think the "caster" (sorry if that's spelled wrong) has something to do with "turn in", but I am an aircraft mechanic and I am no expert in car alignments. The car feels like it "delays" slightly before reponding to steering inputs and then "delays" settling down from that input. I would describe it as "floating", like running too fat of a tire on a skinny wheel. The wheels are 19x8 frt and 19x9 rear. Tires are 215/35/19 frt and 245/35/19 rear (but need to go to 255/35's to completely stop the occasional TCS blip). The sidewalls turn in slightly, so there is no bulging of the sidewall that would cause the same feeling that the car is having. This car is a daily driver, and the recent alignment was done with the factory 16"/17" wheels. If a picture would help, I will try to figure out the dreaded posting procedures this afternoon when I finish installing the rear Eibach springs. Thanks for everybody's time! Have a great Mem. day weekend!
Kary Rutschman (Wichita, Ks.)

 

[Projectguy35]

I forgot to mention the tires were Toyo Proxes 4's. I guess they could have a weak sidewall that allows the sloppy feel? Any input would be appreciated. Thanks, Kary

 

[nsxsupra]

I forgot to mention the tires were Toyo Proxes 4's.

Toyo Proxes 4 are all season tires. They probably will not handle as well as max performance summer tires.

 

[Jin1976]

It might be TCS problem or wheels are too heavy. My friend just been smoked for having all 18 wheels by an IS200.

 

[Projectguy35]

No, I think NSXSUPRA nailed it on the head with the all-season tire diagnosis. I remembered after reading his post that my brother had the same problem with his C5 Corvette when he put on some all-season's so he could drive it all year long. He hated the car after that. The stiff sidewalls of the run-flats made the car feel way more responsive. I suffer from a similar problem, so I am leaning toward a tire change later on and I'm sure it should cure the problem. If it doesn't, it will at least take care of my TCS going off occasionally from the slightly too small rear tire setup. Thanks for your responses. Kary