THE Tire Thread

[alma45]

Fantastic job!! Well done!!
Just a simply (and stupid) question: the sizes between ( ) are in centimetres or what??
Many thanks and good W/end to all of you.

Just the facts ma'am, just the facts.

Please post brand and sizes that you are using (besides the OEMs).

I'm just trying to make a thread that is easy to use for those looking to get something different. Here is what we have so far:

OEM: (Side Height) change from stock
Goodyear
F1 SuperCar
235/45-18 Front (105.75) 0%
315/40-19 Rear (126.00) 0%

Non-OEM:
Michelin
Polit Sport PS2
Sport Cup
245/40-18 Front (85.75) -18.91%
345/30-19 Rear (103.00)-18.25%

Bridgestone
RE050A
RE050A Pole Position
265/35-18 Front (92.75) -13.00%
265/40-18 Front (106.00) +0.23%
255/40-18 Front (102.00) -3.54%

RE050A Scuderia
345/35-19 Rear (120.75) -4.17%

Hoosier
R6
245/45-18 Front (110.25) +4.25%
315/40-19 Rear (126.00) 0%

Pirelli
Pirelli PZero Corsa System * couldn't find a link for the corsa system
235/40-18 Front (94.00) -11.11%
345/35/19 Rear (120.75) -4.17%

*it goes without saying that one should always use caution when deviating from manufacturers original equipment.

 

[Fubar]

Very legitimate question... the real answer is: I don't know for sure. However, according to TireRack's explanation of tire dimensions, all are measured in millimeters (except possibly some commercial vehicles).

I am glad you found the post was useful. :cheers

 

[TO AWSUM]

See Through Tires

Here's a set for you to try.

 

[Kirby Vieira]

Kirby has a set of the PS2's. What's your feeling Kirby? Have you done any suspension mods with the Michelins?

Hi Frank, sorry for the delay in responding...Happy Thanksgiving, Merry Christmas and Happy New Year :banana
A local owner is having some shocks made that will automatically and instantaneously adjust on-the-go and I'm waiting on those because most of my driving is straight line and the PS2's haven't created any suspension issues for me. I got the PS2's for stick and speed and they provide both. The increase in acceleration is dramatic. :cheers

 

[ETW]

I have seen a few GTs with 305/35/20 Nitto 555r in the rear. Anyone here? Might be a good idea for higher powered cars but I dont know how the soft-ish sidewall would hold up around corners

 

[digman1]

I put on the Bridgestones a few weeks ago , and are definately stickier.

Really like tkem.

 

[OzGT]

I have seen a few GTs with 305/35/20 Nitto 555r in the rear. Anyone here? Might be a good idea for higher powered cars but I dont know how the soft-ish sidewall would hold up around corners

Being as the are a drag radial, whilst I'm sure they'd work in a straight line, I would doubt their corning abilities as you have indicated.

 

[conundrum]

It will soon be time to get some new rubber. Anything new on the tire front? Has anyone heard about any additional possibilities to consider now or in the near future?

 

[AZGT]

I have the Bridgestones. Aside from all of the other discussion, one thing I like about them is that they are a little wider so they give a little bit of a sidewall bulge past the rim (see first post in this thread http://www.fordgtforum.com/forums/showthread.php?t=14121&page=2 ). I like that look better than the straight rim / side wall. May not be the best for handling, etc, but next time I need to cut a second off my track time I will worry then :biggrin

 

[paul b]

Just put Kumho Xs's on my Viper,if looks mean anything these should be great. The rears are 345-30's, a little larger than stock but they do come in GT sizes for the fronts. I am going to use these as street tires. These are fairly new on the market so there's not too much feed-back yet.

 

[t32b]

I hope THIS isn't a repeat

Fubar,
I was wondering if you had the means of adding the specs of the (new?) Kumho Ecsta XS 345/30R19. They also have a number of 18's for which specs would be helpful too. Wasn't sure which ones to pick but they do have 265/35/18. Found them at TireRack. Anyone know much about these rim protectors?

Follow up - I found the online calculator and ran the numbers. Small. I guess if you can't lower the car (no Penske's), these aren't appropriate.

Just the facts ma'am, just the facts.

Please post brand and sizes that you are using (besides the OEMs).

I'm just trying to make a thread that is easy to use for those looking to get something different. Here is what we have so far:

OEM: (Side Height) change from stock
Goodyear
F1 SuperCar
235/45-18 Front (105.75) 0%
315/40-19 Rear (126.00) 0%

Non-OEM:
Michelin
Polit Sport PS2
Sport Cup
245/40-18 Front (85.75) -18.91%
345/30-19 Rear (103.00)-18.25%

Bridgestone
RE050A
RE050A Pole Position
265/35-18 Front (92.75) -13.00%
265/40-18 Front (106.00) +0.23%
255/40-18 Front (102.00) -3.54%

RE050A Scuderia
345/35-19 Rear (120.75) -4.17%

Hoosier
R6
245/45-18 Front (110.25) +4.25%
315/40-19 Rear (126.00) 0%

Pirelli
Pirelli PZero Corsa System * couldn't find a link for the corsa system
235/40-18 Front (94.00) -11.11%
345/35/19 Rear (120.75) -4.17%

*it goes without saying that one should always use caution when deviating from manufacturers original equipment.

 

[Fubar]

I was thinking about using some Hoosiers on a new set of BBS wheel I just bought. When reviewing the online PDF from Hoosier it looks like they offer a 345/30 for the rear. Here is my question for the folks using the PS2s (especially those using a Penske set-up)... sense you've lost the most ride height, do you feel that you have lost to much ground clearance? Thoughts?

 

[Fubar]

Fubar,
I was wondering if you had the means of adding the specs of the (new?) Kumho Ecsta XS 345/30R19. They also have a number of 18's for which specs would be helpful too. Wasn't sure which ones to pick but they do have 265/35/18. Found them at TireRack. Anyone know much about these rim protectors?

Follow up - I found the online calculator and ran the numbers. Small. I guess if you can't lower the car (no Penske's), these aren't appropriate.

Done... slight change in the rake, that you would definitely want to adjust for.

 

[Fubar]

I just installed this config:

Hoosier
Radial Wet
245/40-18 Front (85.75) -18.91%
A6
345/30-19 Rear (103.00)-18.25%

Traction is fantastic... my car made 640 rwhp the last time I dyno'd it and I actually get 2nd gear to hook-up now. I may lower my car a bit to fix the extra clearance. Has anyone with similar size tire arrangements dropped their GT to compensate? If so, how much?


It's hard to see the spacing in this photo but there is quite a bit between the fender and the tire.

Lots of rubber on the ground tho:

 

[REDEEMED]

trying to hijack this thread!

OK, so all you tire fanatics... who's bothering to run Nitrogen fills?

Thanks, REDEEMED

 

[Derry]

FWIW,
I see on an internet search that Pirelli PZero system Asimmetrico has 265/40ZR18 and so does sumitomo model HTR Z III
Derry

 

[Mullet]

Fubar

what's the difference in the Hoosier R6's and A6's?

what's radial wet?

I should have my rear 345/30/19 Pilot Cups and front 245/40/18 PS2's on tomorrow.

 

[kumar]

Mark, if you had gotten the 315/40s, you would hook up in 1st.

 

[centerpunch]

Fubar

what's the difference in the Hoosier R6's and A6's?

what's radial wet?

In my opinion, it is potentially very dangerous to mix tire types front and rear, especially on a car with such high limits as the GT. In an emergency situation with extreme braking or cornering forces, the car will possibly respond very differently than its designers intended.

The R6 is a road race compound, the A6 is an autocross compound (for very short runs of a minute or so).

The Radial Wet tire is just that. "The compound for these tires is intended for wet weather use only," per Hoosier, bottom of this page:

https://www.hoosiertire.com/Tctips.htm

 

[Mullet]

In my opinion, it is potentially very dangerous to mix tire types front and rear, especially on a car with such high limits as the GT. In an emergency situation with extreme braking or cornering forces, the car will possibly respond very differently than its designers intended.

The R6 is a road race compound, the A6 is an autocross compound (for very short runs of a minute or so).

The Radial Wet tire is just that. "The compound for these tires is intended for wet weather use only," per Hoosier, bottom of this page:

https://www.hoosiertire.com/Tctips.htm

I appreciate the concern but I am confident in a "extreme braking or cornering forces" the setup I have will perform light years ahead of the crappy Goodyear stock tires. Also, driver experience and skill plays a factor in this once in a lifetime situation and I am confident of my skills.