So Ive gotten the impression that 17s hinder a cars performance. But Im not sure why. I would think its an inertia thing with the bigger wheel.

Does anyone have the full details on why this is and to what extent is saps power?

 

17 h45 3v3|2y7h1|\|g 70 d0 \^/17h 7\^/0 7h1|\|g5: m0m3|\|7 0f 1|\|3|2714 4|\|d 3ff3c71v3 g34|21|\|g.

3v3|\| 1f 7h3 l4|2g3|2 \^/h33l 15 l1gh73|2 7h4|\| 7h3 5m4ll3|2 \^/h33l 17 74k35 m0|23 3|\|3|2gy 70 4cc3l3|2473 4 l4|2g3|2 \^/h33l. 74k3 4 10lb d|2um 4|\|d l4y 17 0|\| 175 51d3. |\|0\^/ 74k3 4 15lb p1p3 4|\|d l4y 17 0|\| 175 51d3. \^/h1ch 15 g01|\|g 70 74k3 m0|23 3|\|3|2gy 70 m0v3?

53c0|\|d 4 l4|2g3|2 \^/h33l 1|\|c|234535 7h3 3ff3c71v3 f1|\|4l d|21v3.

 

Excellent topic for general car chat!

 

good call Silent Bob.

 

well---if you go up an inch in rim size all you have to do is go down an inch in profile and you will have the same overall diameter and nothing will change---this shouldnt be a problem with 17s but it is gets harder when you go with 18 or 19s b/c there is only so small in profile you can go without losing so much sidewall-----if you have a very small sidewall you cant turn at high speeds without breaking the bead----the sidewall is supposed to flex and actually is very important when it comes to racing and handling--there needs to be some sidwall flex to maintain good traction....

 

True to an extent. It comes down to what John said about moment of inertia and getting the object moving. When the wheel gets larger and the tire gets smaller the location of the tires weight is farther from the center of rotation which makes it harder to start the spinning. Since tires tend to weigh more per square inch than wheels. Tires tend to weigh more as their profile gets shorts because of thicker sidewalls. Another analogy: You have a barbell with a 10lb weight at the far ends. Then you slide the same weights to the center. Which is easier to rotate with your hand in the dead center?
Besides 13 steelies on the front with stock 185/70/13s look so much damn racier!

 

Well from a acceleration standpoint they would slow the car down. Take a saucer plate(coffe plateetc.) then take a dinner plate and stand them on their side. Make one full rotation with each plate. Which one went further? Since the dinner plate is larger thus covers more area. So in acceleration(drag racing) a smaller wheel gives the car quicker acceleration. Now on top end the larger wheel(or dinner plate) would be faster. Plus with a smaller rim the tire will have more sidewall. Which will give the tire more of a chance to wrinkle the sidewall(i.e. slicks) If u want a wheel for acceleration go w/ a small wheel. If u want a wheel for more high speed racing then go with the dinner plate uh Im mean larger rim. -Mark

 

So why are the car companies like BMW Mercedes Porche and so one are now building cars with larger wheels ? Or is it the are tuning the cars to be with larger wheels. Another question if you were to take off the 17s on a new BMW and put some 15s on would the car perform better ? Or am I just being a Jack ass again

 

well---that could be true but most tires do not change in weight--and if they do it is such a small amount it is not noticable----a am not saying your wrong---i am just saying that if he changes wheel size and lowers his profile keeping the same overall diameter he shouldnt have any noticable difference in performance or need to have his speedo recalibrated......

 

I would say its for handling and stability. Every drove a van with big mushy sidewalls? You can turn the steering wheel back and forth quick and the whole vehicle kinda bobbles around on the tires. Germans dont like that on the autobahn. Big sidewalls also suck for conering which is probably what those performance cars are after. If you look at newer full size cars they may have 16 wheels but still have pretty tall tires. Another reason may be because 75 series tires just arent in style right now!!

I agree with you there. If the overall diameter is the same he will definatly not need to recal the speedo. There probably wont be any difference in straightline performance either it may corner better though. They probably will be slightly harder to get turning being that the tire weight is more concentrated 1 farther out from the center as before but Im sure you wont even notice it.