Michigan BRZ/FRS Random Chat and spotted thread.

[kberkel]

Originally Posted by R L Newb

I probably should have re-read instead of going off my fuzzy memory of some magazine article on contact patches. you're right, it was based on overall diameter not rim diameter.
There are some interesting notes on contact patch when you're comparing stock tire width vs. race tire width and pressure/sidewall differences. http://www.carbibles.com/tyre_bible_pg3.html

They made a good point on the whole nitrogen thing. I'll read through it all later

[dsgerbc]

Originally Posted by Sccabrz192

You are interpreting it wrong, TIRE circumference, not WHEEL circumference coupled with tire pressure and corner weight makes the difference in contact patch.

That R&T article is junk. Area=corner weight/PSI is BAD approximation.

Wheel dimensions matter, but mostly the width. After that, sidewall stiffness matters a lot more than whether those are 17" or 18".

Here, guys, play with a contact patch calculator based on a fairly decent tire model.

[JDogg]

Anyone going to the xceedspeed BBQ this Sunday?


Sent from my iPhone using Tapatalk

[T_Scott]

Originally Posted by JDogg

Anyone going to the xceedspeed BBQ this Sunday?


Sent from my iPhone using Tapatalk

I would like to go, just nobody to go with.

On a side note, does anyone have any lowering springs they would be willing to let go of? I don't like the stock monster truck status of my car currently lol.

[Sevs753]

Drove from Farmington into Downtown Detroit this morning around 9:30 with a WRB BRZ. Glassman plate frame but no plate. Temp reg in the window. If you see this, congrats on the new BRZ!

[JDogg]

Originally Posted by T_Scott

I would like to go, just nobody to go with.

Where you from? I'm trying to find or make a caravan to go with from the Northville area.


Sent from my iPhone using Tapatalk

[CallmeDave]

I'll be going. Seen a cute gal in a WRB BRZ on Beck road yesterday.

[Sccabrz192]

Originally Posted by dsgerbc

That R&T article is junk. Area=corner weight/PSI is BAD approximation.

Wheel dimensions matter, but mostly the width. After that, sidewall stiffness matters a lot more than whether those are 17" or 18".

Here, guys, play with a contact patch calculator based on a fairly decent tire model.

I wasn't trying to say it was a good / accurate article either but the ones they mention do play the bigger roles, beyond that it's just painting monumentally broad strokes to make it seem like he knows more than R&T readers.

[T_Scott]

Originally Posted by JDogg

Where you from? I'm trying to find or make a caravan to go with from the Northville area.


Sent from my iPhone using Tapatalk

I'm located in Midland

[R L Newb]

The point in the articles, one which I never thought about before reading, is width in a tire doesn't always mean more grip or more contact patch.

[markitect]

My experience on wheel size:

The contact patch can be the same regardless of diameter, if you have the same tread width, the pressure you will want will potentially be different..

What you get with a smaller diameter wheel is a bigger sidewall. This does a few things:
1. A bigger sidewall increases the amount of air you put in. This makes adjustment easier(1 psi is a smaller percentage of the total air), but also makes for greater expansion as you tire heats up(you have more air so as it heats up it expands more).
My preference is to have more air volume, you can then make small air adjustments throughout the day, I do this after each run based on marking the tires, although going off tire temp across the tire is more better if you have the equipment. The exact pressures you want depend on if you are doing autocross or a track day, and many other factors.
2. A bigger sidewall also make the tire more flexible. The flexibility will decrease feel, and make it feel slightly less responsive to steering input, etc. It is not affecting traction, just the initial feel as the tire deforms(until you deform it so much you go on the sidewall). This has the side affect of heating up your tires more quickly as well(more stretch=more heat). This to me comes down to personal preference.
3. You will go through tires, and smaller diameter, higher profile are generally cheaper.

I actually got some cheap cheap 16" wheels this year for the track.

[NJ10]

Originally Posted by Sevs753

Drove from Farmington into Downtown Detroit this morning around 9:30 with a WRB BRZ. Glassman plate frame but no plate. Temp reg in the window. If you see this, congrats on the new BRZ!

Hello there!



That was me. Just got the car on Monday. Glad to be a new entrant in the BRZ group.

[eikond]

Originally Posted by NJ10

Hello there!



That was me. Just got the car on Monday. Glad to be a new entrant in the BRZ group.

Welcome NJ10! I'm a big fan of WRB BRZ's. Nice to have you on board.

Hopefully you can attend one of our get-togethers if we can get our act together and organize something one of these days.

Any plans for modifications?

[JDogg]

Originally Posted by T_Scott

I'm located in Midland

I'm joining up with a caravan leaving from John R and 12 Mile around 8:30am if you're interested.


Sent from my iPhone using Tapatalk