How does changing rims affect cars performance?
 

so if I change the wheels on a car and make them bigger for cosmetic reasons how will it affect or the performance ?

Upgrade your brakes too.

If it's a car or a truck and you significantly increase the moving mass you're going to want to increase the braking power of your car too.

Most people spend their next 5 paychecks on the rims that the extra $2 or $3k for brakes isn't considered.

Brembo makes kits for many popular cars and trucks.

hmm, I always thought custom rims are actually lighter than the stock ones...

Could be good or bad. Bigger wheels could help you transfer more HP and torque to the road, but it could also alter your ride in several ways.

Some are, some aren't. Tuner/racing style rims are usually lighter than stock rims, whereas chrome is almost always heavier.

More rotational mass = more power it takes to make the wheel spin = more power being used by engine.

Not in most cases... A wheel that is bigger and lighter will be very expensive, and no one every buys those, they buy what looks good or what they can get a deal on.

Adding unsprung rotational weight to the car will cause a much more noticeable performance drop than say, adding the same amount of weight in bricks to the trunk. Cars aren't about power, they're about power-to-weight. Dropping the weight off your car has the same effect as gaining the equivilant amount of horsepower...

Of course on a decent car you won't notice anything, but if you've got under 240 horsepower and replace your stock 17" wheels with some 19" chromies, you're going to notice the car is missing a little something when you accelerate through the gears.

That isn't always the case and in any event bigger tires will also affect the result.

Changing wheel/tire dimensions will always impact on a car's handling because of the resulting changes to suspension and steering geometry. If the manufacturer has skimped on wheels and/or tires, such changes might be an improvement, but that is a dangerous assumption.

Changes to the total diameter of wheel and tire will affect overall gear ratios and therefore performance. Moving away from recommended tire types and sizes will often give a poorer and/or noisier ride. Wheel/tire changes often put extra stress on other components which will shorten their life and in extreme cases, prove dangerous.

Unless posing is all that matters, changing any dynamic component on a car is a job for someone who knows everything which needs to be changed to make the new parts work well with the originals that remain.

Botom line. bigger rims = strange gear ratio. Your spedometer will be inacurate and you'll lose HP at the wheels and put more strain on your drive components

And that will piss you off.

Alot. :2 cents:

The big performance factor is weight -- the expensive alloys are much lighter, increasing steering responsiveness.





2hp

My guess is you'll see little to no performance gain.

if you put bigger wheels you should gain 250 hp

Much lighter than what? If you stay at the same size yes, but if you're going taller and wider, you're going to have a hard time finding wheels lighter than your stockers.

I'd never blow a few grand on wheels for a POS. I'm a physics guy. In a thread where the merits being discussed are aesthetic, the desire to make a performance argument seemed to creep in there. The only way wheels affect performance are weight and when they are designed to improve brake mechanism cooling. Like gabe said, most people will never see or feel a difference. It's an aftermarket BS sales pitch. Talk to a Formula 1 engineer and he'll school ya. I don't even own a car.



2hp

:1orglaugh :1orglaugh