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Tire size options for lowered Iroc, and where to find knockoffs?

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Old Nov 21, 2009 | 04:29 PM
  #1  
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Tire size options for lowered Iroc, and where to find knockoffs?

Im looking for some taller tires all around my car and i deffinately need wider ones for the rear! Im wondering what tires everyone is running, and how wide in the rear?

Also, does anyone know where i can find some of these knockoffs? im missing one and cant find them at all!!!!
Attached Thumbnails Tire size options for lowered Iroc, and where to find knockoffs?-100_0461.jpg   Tire size options for lowered Iroc, and where to find knockoffs?-100_0467.jpg  
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Old Nov 21, 2009 | 05:00 PM
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

For taller, go to higher aspect ratio (60 series instead of 40 series).

As for wider, until you get up into a 60 series or more, your pretty limited on width. But even then, you'll still be limited on width, due to the wheel width, Although with the taller sidewall, you'll be able to run wider than usual, due to sidewall flex.

But I gotta ask....Why do you want a taller tire to begin width? It is gonna throw off your speedometer & everything the ECM calculates, based on vehicle speed.
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Old Nov 21, 2009 | 05:12 PM
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

well the previous owner put smaller tires on due to lack of funds. i forgot the tire size on the car currently it 205/55/16, which puts my cat a lovely 1.5 inches from the ground!

and my speedo currently doesnt work anyhow, since i put a newer transmission in and couldnt get the old speedo gear off of it since it was pressed on the tail shaft
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Old Nov 21, 2009 | 06:36 PM
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From: Bertram (outside Austin), TX
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

#1....205s are WAY WAY WAY too skinny for the stock 8" wheel. I'm surprised the beads even seat right!

#2....Just get stock 245/50R16s or even (my choice, especially for the rear) 255/50R16s & you'll be plenty happy.
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Old Nov 22, 2009 | 03:10 PM
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Car: 1986 IROC-Z
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

wont the 50's be shorter than the 55's???


also stephen, you reply to most(if not all) of my threads, your full of info, thanks for all the help man!

Last edited by IROCK ZZ; Nov 22, 2009 at 03:23 PM.
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Old Nov 22, 2009 | 05:03 PM
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

55 is more than 50, but it is a percentage of the 1st number. Like, on a 255/50 (50% of 255=127.5), it will be taller than a 205/55 (55% of 205=112.75).

Beyond that, there is also the possibility of your stock springs being worn some, sagging & lowering the car (because of the worn springs).

Thanks for the kind words. Always nice to hear, even if not expected.
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Old Nov 22, 2009 | 05:04 PM
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

50s are a bit shorter then the 55s. Might try this company for wheels

O. E. Wheel Distributors LLC. Sarasota, Florida. Toll free 1-866-273-3651

They sell a lot of wheels and tires on EBay and have excellent feedback.
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Old Jan 14, 2010 | 01:28 AM
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

205/55-16=24.9"
245/50-16=25.6"

The 245/50 is taller but not by much, the 50 and 55 like Stephen said does not mean the tire is taller/shorter. It's a ratio.

http://www.tirerack.com/tires/tirete....jsp?techid=46


A 165/80-15 (25.4") is not taller than a 235/60-15(26.1"), even though 80 is higher than 60.
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Old Jan 14, 2010 | 09:53 AM
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

Originally Posted by Blind Driver
50s are a bit shorter then the 55s. Might try this company for wheels
Only on the same width tire. Change the width & the ratio calculation goes out the window & has to be redone. A smaller ratio tire could possibly actually turn out to be taller, overall, if the width was sufficient.

Originally Posted by RamAirZ
205/55-16=24.9"
245/50-16=25.6"

The 245/50 is taller but not by much, the 50 and 55 like Stephen said does not mean the tire is taller/shorter. It's a ratio.
Like.....My 315s are the same height as those 245s.

315/35-17=25.7"
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Old Jan 14, 2010 | 11:03 AM
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

Yes sir!! Like my 305/70's on my Rodeo are the same size asa 285/75, just wider.
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Old Jan 14, 2010 | 02:28 PM
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

finally figured out the size i want, 225/55/16 should be perfect.

recommend and good one at a good price?

and the knockoffs are coming off, hopefully ordering some tan iroc center caps next week. someone kicked on of the knockoffs loose and i realized if one came loose on the freeway my rims would be toast!
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Old Jan 14, 2010 | 09:47 PM
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

225's are narrow, i had 225/55/16 on my car when i first bought it, did not like it visually, the tires were too bloated might want to check out some pics on some diff tires sizes, but as mentioned 245/50 is the way to go
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Old Jan 14, 2010 | 10:07 PM
  #13  
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

im just worried about going too big because my car is wayyyyy low. the deflector for the radiator sits maybe an inch off the ground
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Old Jan 14, 2010 | 10:10 PM
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

Originally Posted by IROCK ZZ
im just worried about going too big because my car is wayyyyy low. the deflector for the radiator sits maybe an inch off the ground
hehe....My nose cleared the road kill I straddled today, but the air dam didn't...... I need to look & see if I even still have an air dam!
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Old Jan 14, 2010 | 10:16 PM
  #15  
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Re: Tire size options for lowered Iroc, and where to find knockoffs?

ive had that happen, heard it thump the air dam pretty hard, i dont know how they made those air dams so strong!
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