MCR puts on new rims on their R35

[Pharoahe]

It doesn't look right to me, needs a spacer in the back and 19" is too small for such a big car.

MCR R35 GT-R New Wheels « Kultivate’s Weblog

[mindlessoath]

doesnt matter if its too small for the gt-r.
the 19"s are better for performance. lighter and faster.

[doggiehowser]

Originally Posted by mindlessoath

doesnt matter if its too small for the gt-r.
the 19"s are better for performance. lighter and faster.

Not necessarily.

A well forged design 20" can be lighter than some 19", esp if the design goal of the 19" was to bling things up

I think the biggest gains (to me) besides being able to choose a lighter rim is to open up more tyre choices.

I think there are very very few options for 20" tyres.

[hyrev]

Does not go well at all.

[andreasgtr]

It looks cack imo.
...like spare wheels

[mindlessoath]

With a 13" wheel you will have much better acceleration but horrible top speed.
With a 20" wheel you will have horrible acceleration but much better top speed.

It has to do with gearing. With a smaller wheel you're effectively making your gearing much shorter, so you get up to speed much quicker. With a larger wheel you're making the gearing longer, so top speed increases at the expensive of acceleration.

The larger wheels in turn having a larger tire diameter will only increase ones top speed if the top speed is limited due to the engines redline whether it be you dont want to exceed the redline or the car has a fuel cuttoff at a certain redline. by increasing the tire diameter the circumferance of the tire is increased. so if the car maxes out a a certain mph because the gearing is too low the gearing could "artificially" be lengthened by having a larger diameter tire.

I should have added that it only matters with a gearing limited top speed and not drag or ECU controlled. The larger the wheel the taller the gearing.

However if you go from a 16" wheel to a 17" wheel with a smaller side wall, it IS possible to maintain the same rolling diameter, however, when you get into very large wheels like 19's and 20's it's very hard to stay within factory spec, so your gearing gets taller.

------diff quote
general pros of bigger wheels:
less sidewall flex = crisper handling
assuming they're wider you can get wider tires = more absolute grip

general cons of bigger wheels:
make wheel gap more prominent if you retain the original rolling diameter
usually heavier = more unsprung weight = car must work harder to accelerate and decelerate, acceleration and mileage will be compromised
in general they will ride worse due to the lower profile tires

-----diff quote
Generally, even with equal rim weights, the larger diameter wheel will have greater rotational inertia. And the rotational inertia is what affects acceleration.

Wheel weight affects unsprung weight, which matters for handling responsiveness.

not my quotes.

Tire size calculator
more stuff: Plug your numbers in here - for reference here are stock tires...
Front
Wheel - 20" x 9.5J, 45 Offset, 114.3 PCD, 5 Bolt
Tire 255/40 ZRF 20 (97Y)

Rear
Wheel - 20" x 10.5J, 25 Offset, 114.3 PCD, 5 Bolt
Tire 285/35 ZRF 20 (100Y)


also depends on the tire weight too! those run flats probably weigh alot! if you goto a 19 you have a slightly lighter rim (about 4lbs at least each) which reduces alot of unsprung weight... then removing the heavier runflat tires will also release some weight. (am i wrong in thinking this way?)

[murano3]

Of all the wheels swapped on the GTR these have got to be the worst - for the first time I think the OEM wheels can't be beaten!!.

[mindlessoath]

from what im reading, looks like the GT-R with smaller rim size and tire will reduce weight and make the car accelerate faster but the car will not reach its top speed's. this would be good on small circuits with lots of twists and turns. would set even faster times.

tho i really dont know how well it would do on something like nurinburging, let alone how it would change the downforce and cD numbers.

[Kyuubi]

Those wheels don't go to well with the car..

[rasonline]

10 years ago i'd never have thought 19" could be too SMALL for any car.. but look how times have changed.

I guess we'll see a few bling GTRs with 23" some time in future. it really is ridiculous how big the wheels are becoming.

[ybioul]

I see mine with 22" forged. no doubt.... 265/30/22 in the front and 295/25/22 in the rear both in Pirelli Pzero. have some ideas of which rims...too....
but certianly not these ugly wheels.... this is criminal what they did there.