dvandentop

i know the 1st set of #'s is the width but what about the rest, that is the confusing part.

can anyone post correct sizes that will fit on stock c6 z06 size rims full slick sizes only i already know the dot sizes that fit

thanks
Derek

redtopz

345/30/18 would be:

Width = 34.5 cm / 2.54 = 13.58 inches
Sidewall = 13.58 * 0.30 = 4.07 inches
Diameter = (4.07 * 2 ) + 18 = 26.1 inches.

That is the formula, but the tire specs vary among manufacturers and different sizes. Its best to get the actual specs from hoosier or kumho or brand X from their websites to make sure you get the right sizes. For example I just bought some hoosier R6's and the 285/30/18 tires actually have a wider tread patch than the 295/30/18 but have a shorter diameter so they fit my car better.

BEZ06

Derek

Check out this thread:

http://forums.corvetteforum.com/show....php?t=2050956

Scroll down to posts# 31 and 49. There is some info on sizes, but it's kinda hard to figure out.

All those Michelin slicks are only available for 17" and 18" wheels. I don't think you're gonna find any slicks for an OE C6Z 19" wheel.

Bob

dvandentop

thanks bob i just found that post also

maybe i will go with some wider hoosiers up front like the 285 or 295 since my front 275 hoosiers are shot

bowmanized

SIZE--------TYPE--------------Overall Dia.-----Tread width------Section/Rim------Circ.---- Rim

27/65----18 S7A / S8B / P2C-------648------------- 270--------------296/11----------2010---11 to 12
30/65----18 S8C / S8D-------------653--------------300--------------320/12---------2025-11.5 to 12.5
31/71----18 S9C / S9D / P2C-------708--------------315--------------347/13---------2198--12 to 13.5


The numbers are in centimeters or cm.

The first number is the tread width. So 30 would equal a us 305ish.

The second number is the diameter in centimeters. so 65 is 652mm.

The 30/65 is basically the same diameter 26.8 inches as the stock front wheel but wider being a 305ish in tread width.

In the rear the 31/71 is a little taller, almost 28 inches. That's the newest latest technology that adds a little rake to the car and gives you more forward bite. Also you can get a little better traction with the bigger sidewall.

The inch to mm conversion is 25.4 millimeters per inch. Similarly the inch to cm conversion is 2.54cm per inch.

The confusing part is the 315/30-18. The 30 in the US style is a ratio of the height of the tires' side wall to the width of the tire. It's not really accurate and it would make more sense to just enter the diameter like the Full Race Slick sizes.

Hope this helps.

Thanks,

Mike

On a side note the best setup for the C6Z is the 30/65 and 31/71 rears, the same setups the C6Rs run and the Z06GT3s run. In fact the Michelin Pilot Slicks I carry are exactly the same as most of the FIA GT3 Z06Rs run.

Wilfred Martinez

Check Out this site for easy conversions:https://oneconvert.com/

Aardwolf

Thanks for helping info

BrunoTheMellow

wow very complex answers to a very simple question.
Width (in centimeters if 2 digits or millimeters if 3 digits)
Tire diameter (in centimeters if 2 digits or millimeters if 3 digits),
wheel diameter in inches.

30/65r18 = 30 cm width, 65 centimeter diameter, and 18 inch wheel diameter
same as
300/650r18

just depends on the brand if slick. Michelin uses cm. Hankook and pirelli use mm.

leigh1322

Wider tires on the same wheel helps very little. (Unless the wheels are widened to match.)
Tire and sidewall deflection increases and lifts the inside edge of the tire. Same grip as before but rubberier. Steering wheel response gets worse.
Stay near the max recommended wheel width for for each tire best results.

Check this video out in this thread: (post 22)
https://www.corvetteforum.com/forums...post1607390362

BrunoTheMellow

ehhh… a 305 on a 12 inch wheel is slower than a 335 on a 12 inch wheel.

mfain

Derek,
I am currently running Yokohama A005s in 18" and 19" wheel diameters. Here are the Pirelli 19" slicks available for reference:

Pshoe

Use this.
Race Tire Calculator (braidantire.com)

Shoe

leigh1322

You would think think so...but not always...Maybe...maybe not... only testing will tell for sure...It depends on how much the inside edge lifts....for sure you will have quicker response with the smaller tire.

I have seen dozens of wheel restricted autocross cars run faster on one size smaller tire. It just depends.

Now put the bigger tire on a bigger wheel,,.,and then you have a win-win!