Air bag suspension. Most air suspensions are capable of 0-4" drop at the touch of a button. I have 19" rims with 215/35/19 tires. The car is not lowered at all, but the wheels are so big, they fill the wheel wells out, and most people think the car is lowered. Why did you choose 35 series tires with 18" wheels? 40 series would have been fine and probably wouldn't ride so hard. How much air pressure are you running in the 18's? Did you have the car aligned after installing the wheels??? If not, you should have a 4 wheel alignment done. 18" tires are not cheap and lack of proper 4 wheel alignment will severly reduce your tire life, especially as far as you drive daily!

 

I have 35lb air in the tire and I chose 35 series because that was the tire recomended for 18". I haven't done an alignment yet but it doesn't seem to need it. I like to see a photo of your ride. 19" WOW!!!

 

You should run about 36 psi in the tires. Just because you can't feel the car drifting or pulling, doesn't mean the alignment isn't off. You upgraded the tire size which will change the geometry of the suspension. $89 for a 4 wheel alignment is a small price to pay to ensure long tire life. You should also have the tires rotated every 6000 miles. When they build a new car, the first car for that model year gets an alignment and every other car is built to that same spec. Your car may be 100,000 cars later, something is bound to be off. I bought my car brand new 3 miles on it and the rear alignment was way off. The car drove fine, but drove even better after the alignment. Who recommended the 35 series tires??? When it's time to replace them I would move up to a 215-40-18. You will feel a difference!

 

Thanks for the advice. I check around for an alignment shop in my area.
How about that photo of your car!

 

I am working on it! When you do find an alignment shop, make sure you ask for a 4 wheel alignment, preferrably using a Hunter alignment machine. You do not want a front end alignment.

 

FYI: a 40-series 18 will fit on your P5 and the extra sidewall yields a less punishing ride.

I'm running 215-40/18's on a lowered P5 with no problems.

One more alignment tip: make sure they use some kind of ballast in the car when they align it. If they let you sit in it, that would be perfect, but a lot of shops won't let you do that. Ask about ballast, as your 100-or-so pounds(?) makes a pretty signifigant difference in camber specs.

 

Take a look at my new thread "Baddogs revised '03 MP5". I posted a photo of my car lowered. It's not realy lowered just done so in PhotoShop. This is how it will look when droped!