bigger wheels make it slower?

[NewGolf]

  Glad i chose 17's! 

[gangeox]

This is my 2 penneth worth from what i can remember from college all them years ago:

Bigger wheels give better acceleration.

I you look at it like a 5 speed racing bike if you use a large cog on the front and the big cog on the back you pedal like mad and get nowhere, (i.e. this is used to go up hill) if you use the large cog on the front and the small cog on the back you go faster but at slow speeds its harder to pedal.

However if you use bigger wheels but with a low profile tyre to give the same circumference as the small wheeled tyre it will stay the same.

[Spaced]

Nice to see some love for the standard 17s, I think they have a chunky more purposeful look, and at night in the right light it is difficult to see the difference between the 18s.

Does anyone know the official weight of the 17 and 18 inch Monza?

[NewGolf]

I'd guess the 17's would be lighter as theres an inch less metal! Unsprung weight mass uses the 1:4 ratio from memory, so if they weigh a pound less each wheel x 4 = 16lbs less unsprung weight from the car. It "should" accelerate faster. Low rolling radius should equal fast acceleration, whereas high rolling radius equals lower acceleration but higher top speed.

"Puts his old school physics books back in the loft!"

[182_blue]

there would be minimal speed loss if any, you really would notice it imo, perhaps his was just quicker out of the box or run in differently etc, as for comfort then the smaller the better (or the more rubber the better), then again it wont be as good in the bends and imo doesnt look as good, swings and roundabouts i guess, i read an article somewhere where someone was saying that bigger alloys put on by car makers were killing the ride of most modern cars, and i guess its true

[JonnyG]

In EVO's tyre test last year they found their test GTi was faster on 17"'s rather than 18"s.  They commented on the better turn in and bite with the 17" Bridgestone Potenzas, and they were 2.5 secs quicker than the 18"s Potenzas around a wet track

Personally I found the difference in ride to be very subtle, and not a big difference

But looks wise I much preferred the 18"'s 

[182_blue]

only problem with that pic is as the 17s are closer to the camera they look bigger than the 18's LOL

but yes deffo better looking 

oh and i remember that article, it was more about grip though than outright speed (ie grip allowing more speed around the corners), i guessed (possibly wrongly) he thought it felt faster pulling away etc

[JonnyG]

only problem with that pic is as the 17s are closer to the camera they look bigger than the 18's LOL

Yes, could'nt risk it falling backwards onto the car 

[Hurdy]

The difference in inertial weight will be negligible, I would have thought and so a reduction in accelleration would only be very small.
Similarly you could argue for and against 17" on handling too

a. A smaller alloy gives more in the wall of the tyre and therefore there is less grip....or
b. The smaller alloy gives more in the wall of the tyre and therefore holds on longer in the corners

You decide

[LaserBlue]

yeah the 18s do look far better but i dont know why they gave them that shiny look.. not my cupatea

anybody powercoated any or sprayed them another color?