Wheels and Tyres Diameters and Radius

[Evil_Mx6]

will a larger rolling diam give u the impression of better fuel consumption ? ie more kms to the tank ?

This is wat a stock vr4 has

- 195/60R15 >Search Tires Factory tyres
Tire 1 - 205/55R15 >Search Tires My current tyres
Tire 2 - 215/45R17 >Search Tires Tyres im thinkin of getting

Section Width: 7.67 in 195 mm
Section Width: 8.07 in 205 mm
Section Width: 8.46 in 215 mm

Rim Diameter: 15 in 381 mm
Rim Diameter: 15 in 381 mm
Rim Diameter: 17 in 431.8 mm

Rim Width Range: 4.5 - 7.5 in
Rim Width Range: 5.5 - 7.5 in
Rim Width Range: 7 - 8 in

Overall Diameter: 24.21 in 614.93 mm
Overall Diameter: 23.87 in 606.29 mm
Overall Diameter: 24.61 in 625.09 mm

Sidewall Height: 4.60 in 116.84 mm
Sidewall Height: 4.43 in 112.52 mm
Sidewall Height: 3.80 in 96.52 mm

Radius: 12.10 in 307.34 mm
Radius: 11.93 in 303.02 mm
Radius: 12.30 in 312.42 mm

Circumference: 76.05 in 1931.6 mm
Circumference: 74.98 in 1904.4 mm
Circumference: 77.31 in 1963.6 mm

Revs per Mile: 859.1
Revs per Mile: 871.3
Revs per Mile: 845.1

Actual Speed: 60 mph 100 km/h
Speedometer1: 60.8 mph 101. km/h
Speedometer1: 59.0 mph 98.3 km/h

Speedometer Difference: -
Speedometer Difference: 1.420% too fast
Speedometer Difference: 1.656% too slow

Diameter Difference: -
Diameter Difference: 1.41%
Diameter Difference: 1.63%

im new to this, but im thinkin that by going to the newer type of rims/wheels combo....my cars speedo should show more KMS per tank of fuel am i correct ? or is it the other way around and it will show less KMS per tank of fuel ??

seeing as it has a larger rolling diam and larger radius wont it mean that it
has to spin less to get the same amount of kms?
so in theory been larger in radius and diameter it will cover more area of road and give me more kms per tank ??
obviously im tryin to achieve more kms per tank....
it all sound too confusin....

i done it at; in case anyone wants a crack....
http://www.1010tires.com/TireSizeCalculator.asp?action=submit

 

[JAP63]

Some good points.....
but..
fuel economy is a by product of the accelerator.
It takes does more power to drive them revolutions.

I have 235/45/17...way over stock...(643.3mm rolling diameter.)
My fuel economy is dismal at best.
Leave fuel economy to the control of the right foot.
Dont forget,things become illegal over 630 mm rolling diameter.

 

[Evil_Mx6]

so wat would your avg usage be to a tank with responsible drivin and some fun on the side ??

i currently avg 400-450 tank....or 12-13litres / 100km

i was hopin that with more rollin surface and that i should be able to cover more distance with less roll/ contact on the road...
it sounds a bit confusin but i hope u understand :wink:

 

[Entaran]

12/13L per 100km in mainly city is a good figure. A vr4 won't get much better than that unless you get an aftermarket ecu and deliberately tune it way lean.

 

[87vr4]

my car was tuned wrong to start with which caused alot of WOT problems, but it did acheive on a regular basis nearly 600kms to a tank. 550 around town.

with the tuning corrected, i now see 400 - 450 at the absolute most.

i dont see that increasing the rolling radius is going to make a noticable diff

 

[BobWrinkle]

The smaller the footprint = less drag = better fuel and tyre wear.

So if your after nothing but fuel eco pump ur tyres up as much as they will allow.

 

[Evil_Mx6]

The smaller the footprint = less drag = better fuel and tyre wear.

So if your after nothing but fuel eco pump ur tyres up as much as they will allow.

so a larger rolling diameter should give me better fuel and tyre ?
this is my main concern.

coz the tyres im thinking of getting are gonna be about 10mm larger diameter than the standard set the vr4's come with.

 

[JAP63]

coz the tyres im thinking of getting are gonna be about 10mm larger diameter than the standard set the vr4's come with.

You will not see any economical difference with 10mm...at all.