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Old 03-02-2011, 08:54 AM   #1
BIG KRIS
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20x12 will they fit

Will a 20x12 mount up with no problems with a 7in drop or lower in the rear or will the tubs have to come out?
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Old 03-02-2011, 02:14 PM   #2
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Re: 20x12 will they fit

12" wide wheels will require widening the tubs w/7" drop & allowable 'normal' clearance.
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Old 03-02-2011, 07:47 PM   #3
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Re: 20x12 will they fit

so what would "normal" clearances be?
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Old 03-02-2011, 08:56 PM   #4
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Re: 20x12 will they fit

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Originally Posted by love my 72 View Post
so what would "normal" clearances be?
Min .500" each side.
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.
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Old 03-03-2011, 11:06 PM   #5
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Re: 20x12 will they fit

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Originally Posted by SCOTI View Post
Min .500" each side.
SWEEEEEEEET Thanks scoti!

The narrowest point in the rear wheel wells of my 73 K5 Blazer is 14.25, i guess that means that if my Arithmetic is correct, and i get a 12 inch wide wheel with the proper back spacing i will have 1.125 on either side for clearance.

Now i don't mean to high jack the thread but what tire with run on a 12 in wide wheel?
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Old 03-03-2011, 11:17 PM   #6
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Re: 20x12 will they fit

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Originally Posted by love my 72 View Post
Now i don't mean to high jack the thread but what tire with run on a 12 in wide wheel?
Simple answer. 315/35/20...

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Old 03-03-2011, 11:21 PM   #7
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Re: 20x12 will they fit

Quote:
Originally Posted by love my 72 View Post
SWEEEEEEEET Thanks scoti!

The narrowest point in the rear wheel wells of my 73 K5 Blazer is 14.25, i guess that means that if my Arithmetic is correct, and i get a 12 inch wide wheel with the proper back spacing i will have 1.125 on either side for clearance.

Now i don't mean to high jack the thread but what tire with run on a 12 in wide wheel?
This is what I'm running:

The tubs are narrowed to the frame and I have the narrow 67-70 rearend,
20x12's with 7" backspacing and a 31 x 16 tire but easily coud have run an 18" tire.
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Last edited by Hart_Rod; 03-03-2011 at 11:24 PM.
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Old 03-03-2011, 11:31 PM   #8
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Re: 20x12 will they fit

20x12 315/35/20 6" backspacing on wheel and flip kit. Fit with trimming the fender lip 1/4"
They did rub a little on the inner fender wells when pulling in at an angle so I added a few inches to them.
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Old 03-26-2011, 02:41 PM   #9
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Re: 20x12 will they fit

Woah grande rojo that looks sick. so you didnt need to narrow the rear or tubs or anything, just trim the fenderwell? and what do you mean added inches to them? id love to run that setup on my flipped '80! thanks!
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Old 03-26-2011, 06:52 PM   #10
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Re: 20x12 will they fit

Quote:
Originally Posted by love my 72 View Post
SWEEEEEEEET Thanks scoti!

The narrowest point in the rear wheel wells of my 73 K5 Blazer is 14.25, i guess that means that if my Arithmetic is correct, and i get a 12 inch wide wheel with the proper back spacing i will have 1.125 on either side for clearance.

Now i don't mean to high jack the thread but what tire with run on a 12 in wide wheel?
That math is off. A 12" wheel is actually 13" wide @ the bead (.500 ea side to seat the tire). Then you need to factor in 'tire bulge' which will depend on tire manufacturer.
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Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive.
It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar.....

Cubic inches is like Indiana Jones with a cheap pistol.
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Old 03-26-2011, 09:36 PM   #11
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Re: 20x12 will they fit

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Originally Posted by SCOTI View Post
That math is off. A 12" wheel is actually 13" wide @ the bead (.500 ea side to seat the tire). Then you need to factor in 'tire bulge' which will depend on tire manufacturer.
This is true.
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Old 03-27-2011, 02:00 AM   #12
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Re: 20x12 will they fit

Interesting information scoti,

I allways presumed the measurement was to the outer edge of the rim !!
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