As many of you are aware I just installed a roush supercharger and traction is now an issue.

This is my dilemma. I love the look of my factory 19 inch wheel. These are my questions:

1. How large of a tire can I fit on our factory 19 inch wheels in the rear ?

2. What is a sticky tire that you can recommend ?



I do realize drag radial options in 19 inch are non existent but again I want to keep the stock wheel but want as large and sticky as possible.

Thanks for your help.

 

It depends how wide the factory 19" wheels are.

 

I think you meant 19". If these are the wheels that the OP is refering to, then they're 19 X 8.5.

 

That's the wheel. They look great on my gotta have it green. Would hate to toss them.

 

You won't find a tire to fit that wheel that will hook a Roush blower. The widest you could fit and get all of the tire compact patch on the ground is a 255. But the width isn't what's important but rather the aspect size of the tire. That's why I run a 15" wheel.

 

Without going the above route a 255 is the best bet but it still depends on the maker of the tire. Some run wide, some thin. Direzza II is the one to beat in the Max Performance category. Beat the RIVAL and MPSS.

 

You could run a 265-40-19 on 8.5" wide rims. The lower the aspect ratio the larger the contact patch. I run 255-45-18 on stock 8" wide rims. With a supercharger grip will be an issue.

 

The aspect ratio has to do with the height of the sidewall in relation to the width of the tread. (width/height based off % of width/wheel diameter). Check the recommended parameters for the tire you want based off the width of your wheels.

 

Another way to explain the aspect ratio and contact patch in relation to your tire is to multiply (on a 255-45-18 tire) .40 x 255. That will tell you the percentage of the 255 that is the height (sidewall) of the tire. Tire rack is a helpful site with regards to wheel width and tire size.

 

Yep. That is also true.

 

There's online tire calculators that you can get tread diameter and height with. The issue is that there are no 19 inch drag radials you can use with those wheels. Any performance tire will be less than you really want. You should be able to fit at least a 10.5" tire on those wheels with some sidewall overlap if that helps any.

 

I am familiar with tire calculations and how size is calculated. I was just curious if anyone had any luck with a tire for our 19" tires. I like the wheel and to be honest was hoping I didn't need to go up to a 20" or down to an 18". The other issue is Drag Radials don;t handle corners well at all. So I was hoping to get a stickier tire that would fit our 19" rims that wouldn't compromise handling much either. Yes.........I would like to have my cake and eat it too. LOL

 

MPSS

 

Michelin Pilot Super Sport ?

 

If you have a 19x8.5 you can get more tire than you think on there. I have seen 295's mounted on a 8.5in wheel and no problems other than side wall tucking in. However that is pretty extreme, I wouldn't necessarily recommend that...local tire shop might not even mount it for you.


I do however think you could go up to a 275 with no issues. As mentioned above the Dunlop Direzza II...now in star spec is a great choice. Also great choice available in 275/35/19 is the Hankook RS-3 v2. You aspect ratio should be darn close with that size. These two tires are the winning tire mounted on pretty much all Autocross cars these days.

 

I meant to also note, that a 275 while better than a 255 is still leaving your car under tired for that much torque. If it were me I would find a way to get a 305/30/19 under my ride. Even it meant going to a new set of wheels.


Even Ford saw fit to put a 285 on the back of our cars(sport pkg)...which I think is barely enough, with much less power on tap.

 

Yep. MPSS is a great tire.

 

So after doing a little research I found the solution to my wheel issue. Since I truly do love the factory wheel and can't find a 10" wide option in it anywhere I will send the two rear wheels to weldcraft and have them widened. Check out their site. Cool stuff and they are the real deal. Strength isn't an issue as I have found many people online who use them with excellent results. http://www.weldcraftwheels.com Now I'll be able to get a 305 underneath the back and that should help considerably and I won't have to compromise the factory look I enjoy so much.

 

Sounds like a solid plan.

 

huh, well there ya go. let us know how it works out.