Wider tires in the back of my 03 cobra?

pdiddy80 · 10-08-2006

I have the stock size tires on my 03 svt, 275/40 17
I can not get traction at all in 1st or 2nd. I would like to put on some 315/35 17 in the back. Anyone know if they will rub?

Im sure there is already a post on this somewhere, but if anyone knows, I would appreciate it.

shinerstang · 10-08-2006

My friend has 35's on the back of his and they don't rub. The traction helps a little, but he says it gets a little scary in the rain because there isn't enough down pressure in the back. There must be a better way for you guys to get them to hook up.

Lances03GT · 10-08-2006

You will have to get bigger rims and probally get a smaller IRS bolt.
http://www.maximummotorsports.com/

JD04COBRA · 10-08-2006

I have 295/35/18 on the rear of my 04. My car hooks up very good. I am running BFGoodrich KDW 2 all the way around.
I am still running 275/35 up front. My wheel sizes are 18x8.5 front and 18x10 out back.

pdiddy80 · 10-08-2006

Quote:

Originally Posted by Lances03GT

You will have to get bigger rims and probally get a smaller IRS bolt.
http://www.maximummotorsports.com/

why bigger rims? a 9 inch wide wheel will fit a 315/35 17
Cant I just get the 35 mm bolt on wheel spacers that are on the website u posted, Thanks by the way

pdiddy80 · 10-08-2006

Quote:

Originally Posted by shinerstang

My friend has 35's on the back of his and they don't rub. The traction helps a little, but he says it gets a little scary in the rain because there isn't enough down pressure in the back. There must be a better way for you guys to get them to hook up.

Is your friends a IRS car or a solid rear AX?
I hear you need spacers to avoid the IRS bolt.

Lances03GT · 10-09-2006

Just get the MM IRS bolt and they will fit.

pdiddy80 · 10-11-2006

Quote:

Originally Posted by Lances03GT

Just get the MM IRS bolt and they will fit.

MM IRS Bolt???????
Maybe Im stupid, but whats that?

Lances03GT · 10-11-2006

It replaces the IRS bolt in the wheel well and allow's you to install a wider tire.I tried to do a direct link but it won't let me.

Yes a 315 will fit on a 9 inch rim but why?They look alot better on a 10 or 10.5.

Lances03GT · 10-11-2006

This is what I'm talking about.....

With some of the larger tire and wheel combinations, the tire's sidewall can contact the head of the rearward IRS subframe-mounting bolt. Increased clearance for larger tires can be had with these low-profile bolts. At .350" tall, this low-profile bolt head and washer is 30% shorter than the .500" height of the factory bolt head. Even if there is some slight contact with the tire's sidewall, the nicely rounded head of this bolt will not damage the sidewall as readily as the sharp-cornered factory bolt head.

Sa-When · 11-05-2006

Quote:

Originally Posted by Lances03GT

This is what I'm talking about.....

With some of the larger tire and wheel combinations, the tire's sidewall can contact the head of the rearward IRS subframe-mounting bolt. Increased clearance for larger tires can be had with these low-profile bolts. At .350" tall, this low-profile bolt head and washer is 30% shorter than the .500" height of the factory bolt head. Even if there is some slight contact with the tire's sidewall, the nicely rounded head of this bolt will not damage the sidewall as readily as the sharp-cornered factory bolt head.

Yes you will need the bolts going with a 10.5 wheel.The BFGs 315/35/17 will not fit right on the stock wheel.But the Nittos' will.I ran the 315/35/17 nittos without a problem.They still didn't hook worth a crap on a cold road though.Since I put the 8.8 in I went with the 10.5 rear wheel with the 315/35/17 nittos and it works great at 18psi. on the street or track..

GlennBrown · 11-09-2006

Quote:

Originally Posted by pdiddy80

why bigger rims? a 9 inch wide wheel will fit a 315/35 17

Not really. They will bulge out and not make full contact.