This is me trying to learn about tires

"YSI-what can brown do for you" (ysi-what-can-brown-do-for-you)
09/03/2013 at 14:02 • Filed to: None

And what size is functional for my car...

I am on mobile so I can't post gifs :(

DISCUSSION (25)

ddavidn > YSI-what can brown do for you
09/03/2013 at 14:10

I'm sure you've seen this, but I will just post it anyway. http://www.tirerack.com/tires/tiretech…

shpuker > YSI-what can brown do for you
09/03/2013 at 14:13

It's simple. First number is the footprint, aka the 225=225mm footprint. Second number is the percentage of the first number the sidewall rubber is of that footprint. AKA a 335/40R17 is a much lower prof. than a 335/60R17. And the overall side profile is the rim size+the side profile. AKA total side=(335*.40+17*2.54(in->cm))

YSI-what can brown do for you > ddavidn
09/03/2013 at 14:14

It isn't really about that it is more about how wider tires don't mean more grip...but they can though but sometimes they don't. Or how a larger wheel will mean slower speeds unless you get a smaller sidewall but then you have to account for the larger diameter...

In the end all I have come up with is, I don't know.

ddavidn > YSI-what can brown do for you
09/03/2013 at 14:15

Oh, you mean physics. I don't get any of that either. Not a problem, though since I stay with stock sizes.

YSI-what can brown do for you > shpuker
09/03/2013 at 14:15

The numbers make sense it is the physics behind tire that confuse the shit out of me. It is seriously just a bunch of "it might or it might not."

YSI-what can brown do for you > ddavidn
09/03/2013 at 14:16

Yeah but my stock tires suck for autocross where tire grip is king!

ddavidn > YSI-what can brown do for you
09/03/2013 at 14:18

Ah yes, I also have a dream of going to the autocross... Or rallycross... Good luck getting some grip, then!

YSI-what can brown do for you > ddavidn
09/03/2013 at 14:19

I need all the luck I can get, I can feel a giant migraine coming due to this...

shpuker > YSI-what can brown do for you
09/03/2013 at 14:20

Wider tire will give better cornering grip than a similarly sticky narrower tire but will have really no benefit in launches. However it will help keep you pointed straight.

Oh and a larger overall diameter will cause you to cover a larger distance per-rotation, thus your speedo may say 50 when you're doin 55. Vice versa is also true obviously.

And a 305/45 will have nearly the same sidewall height as a 335/40.

shpuker > YSI-what can brown do for you
09/03/2013 at 14:20

Saw that in the other one. Maybe that'll help?

shpuker > YSI-what can brown do for you
09/03/2013 at 14:25

Or I'll put it this way. The ideal for auto cross would be a sticky tire with a stiff sidewall (all-seasons and performance tires have very different sidewall stiffnesses). However going too stiff or too sticky can be bad as well. Super sticky tires and stiff tires can wind up being too stiff or too sticky for auto cross as its a bitch to keep heat in your tires at lower speeds. AKA don't buy R compounds. But those are expensive as fuck so you probably wouldn't want to anyways.

Yay tires.

YSI-what can brown do for you > shpuker
09/03/2013 at 14:28

This is exactly what I was thinking as well, but after reading an article I don't know what to believe. Although, I have heard a larger wheel will slow you down(even with similar weight), I hope it is negligible. I want wider wheels(grip) but larger diameter ones as well(looks)...

shpuker > YSI-what can brown do for you
09/03/2013 at 14:31

A larger diameter wheel will almost always take a lower prof tire. So the overall diameter shouldn't change much if done right. But if you go and throw 20's on her she's probably not gonna corner very good.

Basically, heavy rims are a bad idea (rotational mass has a much larger affect than dead weight) however a stiff wheel that weighs as much or less than stock with lower prof sticky tires is a great combo.

YSI-what can brown do for you > shpuker
09/03/2013 at 15:32

The wheels I am getting are about a pound lighter than stock and it is a 18x8.5! The diameter won't change if I put 235 or 245/35s(only 3mm difference!) on the car the diameter will be exactly the same. Hopefully the ride won't be too bad and hopefully the wheels can take it. If anything I can go with a 245/40, which is about an inch larger in diameter. . .

shpuker > YSI-what can brown do for you
09/03/2013 at 15:47

I'd go anywhere from 240-250. So common sizes yea 245/40. What're the stock tires?

YSI-what can brown do for you > shpuker
09/03/2013 at 15:52

The stock ones are 215/45, they are also pitiful when you ask it to offer some sort of grip.

shpuker > YSI-what can brown do for you
09/03/2013 at 15:53

http://www.tirerack.com/tires/tires.js…

Those will tear your face off if you use them for Auto-X . They're fantastic. Had them on my WRX for a while.

YSI-what can brown do for you > shpuker
09/03/2013 at 15:57

Those aren't so badly priced, but how long do they last? I don't want to keep changing tires every 3 or 4 months. If they go for 25k+ then they are good!

shpuker > YSI-what can brown do for you
09/03/2013 at 16:02

Well they're Prius tires so I wouldn't expect much. at 245/40 you're gaining about 5mm in overall height, which is pretty negligible, just over 2% difference.

YSI-what can brown do for you > shpuker
09/03/2013 at 16:06

I was reading an article about wheel+tire weight and height making a difference in performance. Some guy got wheels that were 4lbs lighter so 16lbs savings in unsprung weight(which really does help in corners), he improved his 0 to 60 time by 0.2seconds. . . real big difference.

shpuker > YSI-what can brown do for you
09/03/2013 at 16:07

Depends how often you Auto-X them. Once a week and I'd say you could probably get 20k assuming your daily drive is as long as mine was. If you get 25k out of them while tracking on them I'd say you need to drive a bit harder on the track/go more often.

shpuker > YSI-what can brown do for you
09/03/2013 at 16:08

I could see it. I'd say 0-30 times would be a shit load quicker, but 40-70 times would be nearly identical. 60-0 would probably better too.

YSI-what can brown do for you > shpuker
09/03/2013 at 16:09

I probably will never go to the track(maybe once a year maybe). Plus my daily depends, in the summer it is about an hour altogether, during school. . . maybe 10 minutes(I take the bus everywhere!) I autocross maybe once or twice a month. Looks like 25K is within sight!

YSI-what can brown do for you > shpuker
09/03/2013 at 16:10

Well hopefully my weight will stay the same(about 40lbs per corner), so no gain no loss.

shpuker > YSI-what can brown do for you
09/03/2013 at 16:14

Probably won't change much.