What are the lightest wheels for this car?

[xwd]

It depends on your application. Lots of people on here autocross and for autocross a larger diameter tire is faster in almost all scenarios, period due to the transitions and tighter corners. If you are running a 17x9 rim you need to be running a 245/255, but the classes you run those tires in also allow enough suspension modifications to take advantage of it.

In "stock" class I run 245/40/17 Hoosiers on a 17x7 rim, it's the absolute fastest tire for this car for that class in autocross.

On a track, it's a different story, large tires like that can hurt you with their rolling resistance .

[diss7]

I agree with your point, on the assumption that an r rates / semi is specifically excluded from that event. If not, then I would fail to see how a wide road tyre is going to out perform a 215 tyre with a more competition orientated compound.

[Diode Dynamics]

These HRE's



At 20K a set...they better be the lightest wheels lol

Nick C.

[G_Ride]

Originally Posted by Diode Dynamics

These HRE's



At 20K a set...they better be the lightest wheels lol

Nick C.

I'd love to see how these are made!

[Suberman]

Originally Posted by Admiral Ballsy

I don't believe it's really that simple.

Assuming you're comparing two setups, same section width tires and same wheel width, but different wheel diameters, I think the change in centroid would be extremely minor. The tire gets heavier, but its centroid will shift closer to the hub center.

Since you're only adding sidewall to the tires, the tread mass stays the same and stays in the same location WRT hub center. You're making the sidewalls taller, which effectively shifts the center of their mass to towards the hub.

Obviously if you're changing widths of the tire or wheel or both, then it really comes down to the measurements.

How much it matter depends upon a lot of things - how much heavier is the tire being the main one. But it's not necessarily true that going from, say, 255/50-17 to 255/40-18 significantly changes the moment(s) of inertia.

It does because solid aluminum is heavier than air.

It is also a common misconception that tire section affects grip, it doesn't. Rubber compound affects grip, period. Contact patch area is proportional to vehicle weight and tire pressure, section profile is not relevant to that.

It is called a coefficient of friction for a reason.

Otherwise, children wouldn't be able to walk because their shoes were too small.

Think about it. Think hard before you post any reply to this.

[diss7]

Originally Posted by Suberman

It does because solid aluminum is heavier than air.

And combined with that, the 255/40 tyre is further away from centre of hub

[fatoni]

Originally Posted by Suberman

It does because solid aluminum is heavier than air.

It is also a common misconception that tire section affects grip, it doesn't. Rubber compound affects grip, period. Contact patch area is proportional to vehicle weight and tire pressure, section profile is not relevant to that.

It is called a coefficient of friction for a reason.

Otherwise, children wouldn't be able to walk because their shoes were too small.

Think about it. Think hard before you post any reply to this.

tire section absolutely affects grip. the contact patch most likely doesnt grow in a significant way but it does change shape. even if you dont agree with that, wider tires will allow you to run lower pressure which will increase contact patch size. with my narrow road bike tires i have to run 110 psi while on my mountain bike i can run 30. its the same for cars.

[diss7]

Re-read last two sentences of the post you quotes.

Hint - section profile.

And answering your point, width can add grip. Compound will add grip.

[fatoni]

Originally Posted by diss7

Re-read last two sentences of the post you quotes.

Hint - section profile.

And answering your point, width can add grip. Compound will add grip.

guess that makes me look stupid. thanks for correcting that jazz.

[Diode Dynamics]

Probably Dymags, but they are super expensive

Nick C.

[adprokid]

[DeaconRoc]

Konig daylites
17x7"
Et40
7kg (as weighed on my scales) - 6.5kg claimed

[stevo_12v]

SprintHart CP-R 16x7 +35 : 4.9kg(from wheelweights.net)

I'm rocking these as my daily/track wheels until I wear them out. Made the silly mistake of getting 225's on them when I should have went lighter 205's with a stickier compound.

Wheels feel much faster than my WedsSport TC105N setup(6.75kg rim) though.

[86Toyobaru]

KONIG RRF02
15" 4.78kg
17" 6.5kg (14.3lb) ~$180