17s versus 18s

Mustang5L5

That is…until I whipped out my Bissell

Mod Dude

Feb 18, 2001

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#21

• Aug 4, 2006

• #21

Even if you could make a 17" wheel and 18" wheel weight the same, the 18" wheel will rob more energy to spin.

 

8

8950HO

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Mar 31, 2005

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#22

• Aug 4, 2006

• #22

I e-mailed Maximum Motorsports a while back asking them about 18" wheels.

They said they are used mainly for the bling factor and not for performance.

They also said you will likely loose traction sooner with an 18" wheel and rubber band tire,because there is no sidewall flex which acts as an additional spring in their words.

These are things I had already assumed,plus the additional weight doesn`t help performance which they mentioned.

Big wheels seem to be a trend today,however big isn`t better if performance is in mind when it comes to wheels.

18" and larger wheels are a waste of money,unless you`re a bling boy and favor looks over performance.

 

helty

some Ukrainian's enjoying a handjob via my credit

Mar 30, 2005

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Baltimore, MD

Aug 4, 2006

#23

• Aug 4, 2006

• #23

How about this: get the 18" for the street bc they look awesome

Then save up and get 15" Prostars for the track

thats what Im doing. Its not like 17" wheels are ideal for the track either.

 

Mustang5L5

That is…until I whipped out my Bissell

Mod Dude

Feb 18, 2001

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Aug 4, 2006

#24

• Aug 4, 2006

• #24

8950HO said:

I e-mailed Maximum Motorsports a while back asking them about 18" wheels.

They said they are used mainly for the bling factor and not for performance.

They also said you will likely loose traction sooner with an 18" wheel and rubber band tire,because there is no sidewall flex which acts as an additional spring in their words.

These are things I had already assumed,plus the additional weight doesn`t help performance which they mentioned.

Big wheels seem to be a trend today,however big isn`t better if performance is in mind when it comes to wheels.

18" and larger wheels are a waste of money,unless you`re a bling boy and favor looks over performance.

Click to expand...

That's true and all, but at what point does a larger wheel diameter start to hurt performance? WHo is to say that anything over a 16" wheel isn't best for performance? Why are 17's ok but 18's are a waste? After all it's only 1"

To set a standard like that is not easy. There are just way too many variables to take into account.

 

8

8950HO

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#25

• Aug 5, 2006

• #25

Mustang5L5 said:

That's true and all, but at what point does a larger wheel diameter start to hurt performance? WHo is to say that anything over a 16" wheel isn't best for performance? Why are 17's ok but 18's are a waste? After all it's only 1"

To set a standard like that is not easy. There are just way too many variables to take into account.

Click to expand...

Standards/variables.
The lighter the wheel the better the performance/braking.Less rotational mass
from a smaller wheel is a gain compared to a larger heavier wheel.

Theres no way around this fact.

Testing different size wheels on the same car is the only way to find out.

 

P

Pennywise2

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May 16, 2006

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Aug 5, 2006

#26

• Aug 5, 2006

• #26

I think the 18" wheels look the best and they fill the wheel well's
better.I am considering getting 18X9 FR500's for my mustang.
Does anyone have pics of their FR500's they would like to share?

 

helty

some Ukrainian's enjoying a handjob via my credit

Mar 30, 2005

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#27

• Aug 5, 2006

• #27

jasons got some good ones, Im sure he'll be more than willing to post them up.

 

P

Pennywise2

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#28

• Aug 5, 2006

• #28

Jason will you post picks of your chrome FR500's please?

 

S

san~man

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Aug 5, 2006

#29

• Aug 5, 2006

• #29

Mustang5L5 said:

Even if you could make a 17" wheel and 18" wheel weight the same, the 18" wheel will rob more energy to spin.

Click to expand...

How can you say this when, assuming you have the same over height due to a lower profile tire on the 18" rim versus the higher profile tire on the 17" rim, rotational mass would be the same (given tire weights being the same)?

 

DocG

5th graders > me. They're not bant

Sep 25, 2005

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#30

• Aug 5, 2006

• #30

I'm no physics genius, but would the energy required to rotate the two be different....assuming an 18" wheel which is heavier but has less tire on the outside. Heavy inside, lighter outside. VS. 17" wheel with heavier tire on outside. Lighter inside, heavier outside. I know its not by too much of a weight difference, but since this seems to be some of the arguments. Even if the weights were exactly the same, wouldn't the different distribution of weight affect the rotation and energy?

Pennywise, if you're gonna buy 18" FR500, get 10"s out back!

 

mity2

I like Pro3 and all I got was this crappy CT.

Jul 24, 2003

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Aug 5, 2006

#31

• Aug 5, 2006

• #31

i think our car - considering size of wheel opening, 17" just dont look big enough. especialy if its lowred. and with some kits(like my roush), 17 would look poo, and 18" are pretty much mandate.

but thats me

 

Susky

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Oct 5, 2005

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#32

• Aug 5, 2006

• #32

I have to think that the difference in terms of rotational inertia, while arguable, is not a huge deal. At least not unless you're talking about autocrossing or some other racing when you are working out on the edge. For my uses, though, the weight difference seems negligable.

 

Susky

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#33

• Aug 5, 2006

• #33

Oh, and if you're going to seriously consider wheel/tire mass, you'd have to also taking width into account. After all, a 10" wide wheel is heavier than a 9" wide wheel.

 

Mustang5L5

That is…until I whipped out my Bissell

Mod Dude

Feb 18, 2001

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Aug 5, 2006

#34

• Aug 5, 2006

• #34

san~man said:

How can you say this when, assuming you have the same over height due to a lower profile tire on the 18" rim versus the higher profile tire on the 17" rim, rotational mass would be the same (given tire weights being the same)?

Click to expand...

I knew someone would ask this.


Ok, assume you could make a 17" and 18" wheel weight the same with the same tire width and everything. The reason the 18's still take more energy to spin is due to the majority of wheel mass being moved outwards.

The majority of the mass of a wheel is in it's rim. The spokes don't really weigh all that much.

Simple physics really. Same principles as levers in terms of mechanical advantage. The farther away a mass is from the center point, the more energy it takes to move. Bring it in and it's easier to move.

Now since most 18's weight more than 17's, add that to the equation.