I am thinking of going to 18's for tracking purposes. I am told there will be less rotational mass leading to faster lap times. 18's are also cheaper to replace tires.

Has anybody done this for racing purposes (I'm not inquiring on 18's for a winter set up) ?? Any input?? Thanks

 

I say get some nice lightweight 18" rays/volks for the track.

If it was me i wouldnt keep em on for daily driving but for track would be great. Just my opinion

 

Yup definitely light weight 18s for the track I say. Light weight brake rotors too while you're at it. Stainless Steel clutch & brake lines, Transmission oil cooler there's a whole list of upgrades you'll need to do.

 

Don't forget the other huge advantage of smaller diameter wheels,

19 + 6 (tires) = 25
18 + 6 (tires) = 24

24 / 25 = 96%

25 * 3.14 = 78.5 * .96 = 75.36

78.5 inches per rotation versus 75.36 inches per rotation.

Basically it equates to atleast a 4% gear reduction if you use tires with similar sidewall heights.

My first PDX was at Mid-Ohio and one of the first things my instructor said about my car, was that it had really long gears. I pretty much drove the whole track in 3rd.

Also don't forget that it will bring the majority of the rotional mass (surface area of the tire) 1 inch closer to the axis by radius. The larger the distance from the axis, the more the weight will affect the rotational inertia.

***I don't claim to be a physicist, I'm going by what I've been told

 

Daym never would've put that much thought into it. Just figured smaller wheels= lighter weight= easier rotation, better grip, better steering response and pickup

Just the dumbed down version of what rossab said lol

 

Sounds Good...thanks...Has anybody with a sport model found some lighter weight 18's that fit properly??

 

you can get the 350z anniversary 18s

 

I would think any 18" rays or volks that fit the z should b fine with the right spacers/offsets

 

Might want to look into Rota wheels as well, they're lightweight and cheap, perfect for track. Huge in the Subaru and Evo crowd.

 

RPF1's. 18x8.5 and 18x9.5

Lightweight and cheap