I know 235/40/17 will fit the stock 17's. My question is, how much do I need to lower the car to keep it from looking "floaty" - to much gap between the tires and the body of the car? I want to keep the stock 17's for two reasons:

-Stock look
-$$

With that, the tires I REALLY want - Falken RT-615 - come in 225/45/17 and 245/45/17, but 235/40/17, and from what I understand, 245 would be to wide of a tire to fit the stock 17" wheels.

Thanks for the help!

 

i have seen a 45 series tire on 17 inch sedan wheel and trust me it doesn't look right. The car is too big for having 40 series tire on a 17 inch rim or even 45 series. So to answer your question, there is not a specific amount of drop that will fix the look of your car with 40 series tires.

 

No, it is not a good look. I lowered about 1" and occasionally scrape speed bumps with my Y-pipe.
235/40 are 0.6" shorter overall than my 225/45, so you will be at real risk ripping your exhaust off.

 

http://www.falkentire.com/rt615_sizes.html

Falken says 7.5 rim is minimum they suggest, I would go with that and say no since the stockers are 7". In addition, you should check out how far off you will be from stock overall diameter and how far off your speedometer will be. Plus all the other reasons already mentioned...

 

+1. that's 1.9" shorter than stock, so if you lower it 1" with those tires that's like a 2" total drop. Definately check the numbers.

http://www.miata.net/garage/tirecalc.html
http://www.1010tires.com/TireSizeCalculator.asp
http://www.discounttire.com/dtcs/infoTireMath.dos

 

I checked the tire calculator and 245/50/17 will fit a 7" and keep your diameter, speedo, and stock perameters pretty close....now as for the width?