performance is lagging

ever since i put on my 18" rims my ride has been slower. then a piston rod broke in my engine, and my cv joints went bad in my right side are these all because of my rims or not. and what can i do to improve my performance on my car?

18" rims are usually big and heavy, so what do you expect? Swap in a SR20DET.

The motor has to put out more unneccessary effort to move a bigger wheel. More effort is also required to move a heavier wheel. Being a bigger wheel means the gear ratios are off, thus giving you the slower pick up. The extra weight makes the car struggle more at the moment of inertia and use more power to keep the drive wheels turning. So basically, you're straining your motor to look good. Of course, a modded engine helps, not as much as if you removed those 18's in favor of 15's or 16's.:D

If you get, or read Sport Compact Car Magazine, they had some good write-ups on understanding how wheel weight affects a car's performance. The math wasn't perfect, but it gave you a good idea of what to expect. I'd guess it was about a year or so ago they published this stuff? It was in technobabble or the slip angle, i can't remember off the top of my head at the moment. Hope this helps.

Originally posted by nis.k.a.
Of course, a modded engine helps, not as much as if you removed those 18's in favor of 15's or 16's.:D
Or 17's. That would be you best bet for performance and looks.

Originally posted by Mrcoilover

Or 17's. That would be you best bet for performance and looks.
Not best for all around performance. A 16 with a 45 is probably the better happy median.

Originally posted by nis.k.a.

Not best for all around performance. A 16 with a 45 is probably the better happy median.

But you forgot about looks.