Decreasing Wheel diameter while increasing the width

[BlackMagicSir]

Hi guys, I see most people are upgrading their wheels with larger diameter wheels (18's) which are also wider. I saw a video where it said that this negatively affects the acceleration of the car because of the larger wheel size and the wider tires.

If I got a pair of wheels that have a smaller diameter (say 16's) but wider than stock (say 8.5 or 9), how will this affect my handling and acceleration?

How will it affect my vehicle if I paired these wheels with wide/thick tires?

Sorry if it seems basic to some of you. Thanks for the feedback.

[Gunman]

Tire size can be used to compensate.

example, if you go to a 17x9 wheel, and 245-40 tire, the rolling radius is almost identical to the oem 17x7 with 215-45 tire.

If you go to a 16" wheel, you'll need to increase the sidewall height of the tire, to maintain the oem rolling radius.

[mwjcyber]

Originally Posted by BlackMagicSir

Hi guys, I see most people are upgrading their wheels with larger diameter wheels (18's) which are also wider. I saw a video where it said that this negatively affects the acceleration of the car because of the larger wheel size and the wider tires.

Acceleration is affected by the mass of wheel/tire, and the potential change of gear ratios. So what the video was inferring is the larger the wheel and wider the tire, the heavier they are. Also as wheels get larger, the rotational mass moves further from the hub center, affecting the rotational inertia. Thus requiring more power to make the wheel roll, making the car feel slower.

Lastly if the overall tire diameter is greater than stock, you've now changed the ratio of engine speed to wheel rotation speed, in essence making all the gears taller. But on the bright side you'll get better mpg when cruising at highway speeds with your lower RPMs.

Google'd this, and found the below article. Kinda long read but might answer all your questions.
http://www.tuneruniversity.com/blog/...n-performance/