Post by
Larz »
https://forums.nicoclub.com/larz-u216291.html
Thu Feb 19, 2015 11:39 am
Well stated, Debonair. In fact I saw a vid the other day. Nissan did a test with a factory car that came off the line with 18 inch wheels and they replaced the wheels with 20s. They had engineers from the factory and experts in wheel / tire handling drive the car in factory set-up, then with 20s. They were able to measure the changes in the behavior of the car as well as report on the handling and how each was affected.
The end result was the 20s raised the center of gravity of the car, making it less stable and controllable at speeds similar to hwy speeds. The 20s decreased the handling in turns (sharp and average turns), decreased the grip on wet roads, and increased the stopping distance - all making the car less safe, even in the hands of professional drivers.
If you are increasing the wheel size, you must consider how much increase in size, how much higher the car will sit, and then consider modifying the suspension to keep the car grippy, safe, and easy to handle in a tricky situation.
I am going from factory 18x8-47 to 19x8.5-40. I am also decreasing tire size from factory 245/45 down to 255/40 and that will negate about 95% of the changes caused by the larger wheels. I will maintain near-factory car behavior without needing to modify the suspension. If I went up to a 20in wheel, the suspension would definitely have to be modified to keep the car behavior in a safe range.