Can I run 305 r35 20 in rear

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pitmanr2003

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It's supposed to be an inch but it came down just a bit farther than an inch.
ok im thinking of the sr performance springs that claim 1.2 front and back on covertible which is what i have
305s on a 10" wheel is not a good match. Look at the photos that have it done you will see that the tire is pinched and actually beginning to lift the edge of the tire off the ground as the sidewall isn't supported properly. I wouldn't go beyond the 285 out back for a 10" wide wheel. I know people do it but its not optimal.
wow wasnt aware of that. i have read tons of people running it without issues also its a set package on American muscle and other sites like that. im probably going to buy all new wheels and tires and sell my ones i have now.
what size should i go with for wheels. want to do staggered and flush with side walls no sticking out

 

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ok im thinking of the sr performance springs that claim 1.2 front and back on covertible which is what i have

wow wasnt aware of that. i have read tons of people running it without issues also its a set package on American muscle and other sites like that. im probably going to buy all new wheels and tires and sell my ones i have now.
what size should i go with for wheels. want to do staggered and flush with side walls no sticking out

10" is the minimum for safety, but you will get no benefit from it as the sidewall isn't supported. Look at most measurements that a manufacturer gives for a 305 tire, the measurements are based on a 11" wide wheel. You may put a 305 tire on a 10" wide wheel but it won't look that wide. Think about it...a 305 tire is 12" in width but you are putting it on a 10" wide wheel vs. an 11" wheel.

I would go with the 10" ET35 front and 11" ET 50 rear. Very common for our cars. I am not a fan of 35 series tires on a 20" diameter wheel. A 305/35/20 is a 28.4" tall tire vs. 27.4" that a PP1 car has. Normally a 35 series tire is on a 19" wheel. For 20" diameter wheels I prefer a 30 series. If you plan on lowering I would definitely stick with a 30 series tire on a 20" wheel. This is personal preference. If you are going to do new wheels get function and beauty together. Try and reduce unsprung/rotational weight. I run the SVE X500 wheels in 19x10 and 19X11 and I save almost 40lbs of rotational mass with a 285/35/19 and a 305/35/19.

I do realize that opinions are like assholes...everyone has one.
 
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pitmanr2003

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10" is the minimum for safety, but you will get no benefit from it as the sidewall isn't supported. Look at most measurements that a manufacturer gives for a 305 tire, the measurements are based on a 11" wide wheel. You may put a 305 tire on a 10" wide wheel but it won't look that wide. Think about it...a 305 tire is 12" in width but you are putting it on a 10" wide wheel vs. an 11" wheel.

I would go with the 10" ET35 front and 11" ET 50 rear. Very common for our cars. I am not a fan of 35 series tires on a 20" diameter wheel. A 305/35/20 is a 28.4" tall tire vs. 27.4" that a PP1 car has. Normally a 35 series tire is on a 19" wheel. For 20" diameter wheels I prefer a 30 series. If you plan on lowering I would definitely stick with a 30 series tire on a 20" wheel. This is personal preference. If you are going to do new wheels get function and beauty together. Try and reduce unsprung/rotational weight. I run the SVE X500 wheels in 19x10 and 19X11 and I save almost 40lbs of rotational mass with a 285/35/19 and a 305/35/19.

I do realize that opinions are like assholes...everyone has one.
Thanks bthat makes sense cause I converted b305 mm to in and saw 12 inches and was like how does that work on 10 inch. Lol
 

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Yeah, don't do 305 on a 10" wheel. Definitely look into getting a wider wheels for that.
 
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pitmanr2003

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Yeah, don't do 305 on a 10" wheel. Definitely look into getting a wider wheels for that.
Looking around at prices and 11inch wheels are 2 to 3 times as much. Maybe I will stick with 285. I'm not racing nthis this thing. Im going more for looks being it's a vert. I don't have traction issues now anyways. Just like the wider look
 

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I have the American muscle PP style wheels in 20 x 10 in the rear. Running a 285 now but want to go to 305. It's 2015 convertible GT and plan to put SR performance springs that lowers convertible 1.2 inches all around. Let me know if I will have rubbing issues
Lower the car first, then assess. A 1.2” rear drop with a 305/35/20 will be on the edge for clearance issues; camber and backspacing are key variables.
 
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Lower the car first, then assess. A 1.2” rear drop with a 305/35/20 will be on the edge for clearance issues; camber and backspacing are key variables.
Yes that's what I've decided. I think after looking at some other cars with the springs I want they look about like what I want to achieve. Plus springs are 189 verses 1000s for wheels and tires. 😀
 

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That is great that you have re-thought what you want to do. Often we get something in our minds and it is hard to get past it. Those 285's will work fine and looks are in the eyes of the beholder. :)

Yes that's what I've decided. I think after looking at some other cars with the springs I want they look about like what I want to achieve. Plus springs are 189 verses 1000s for wheels and tires. 😀
 

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I have the American muscle PP style wheels in 20 x 10 in the rear. Running a 285 now but want to go to 305. It's 2015 convertible GT and plan to put SR performance springs that lowers convertible 1.2 inches all around. Let me know if I will have rubbing issues
Yes you can. I have them on the Vox PP 20-inch knockoffs. But man, they are HEAVY.
 

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also, different manufactuers make different width tires irrespective to the size on the side wall. Meaning you can buy 285 tires and depending on the aspect ratio say between a 285/35/20 vs a 285/30/20 the actual measured widths would be different. The 285's that I run are the width of some other companies 295 series tires. You should get the car lowered first then look at wheels and tires, then get an alignment after they are installed.
 

 
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