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quick backspacing question

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Old Aug 6, 2013 | 09:54 PM
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quick backspacing question

i wanted to know what the maximum backspacing is that you can fit on a third gen on the front and the rear without any modification to the car. can anyone help me out
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Old Aug 6, 2013 | 10:04 PM
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Re: quick backspacing question

What diameter wheel makes a big difference. What you looking into?
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Old Aug 6, 2013 | 10:11 PM
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Axle/Gears: 4th gen 10 bolt 3:73 Richmond gears
Re: quick backspacing question

im looking at 17 inch.
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Old Aug 6, 2013 | 11:16 PM
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Re: quick backspacing question

Somewhere around 5.5" depending on the actual wheel. It is dependent on the shape of the inner wheel shell where it is close to the tie rod.
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Old Aug 7, 2013 | 10:12 AM
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Re: quick backspacing question

I have 17x11 wheels on back with 5.5" of backspacing - they stick out. It looks like I could easily do 6" backspacing, maybe 6.5". There is a guy who ran 7" of backspace on the rear, but he had to do some massaging of the inner fender wells.

Last edited by 89mulletbird; Aug 8, 2013 at 01:17 PM.
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Old Aug 7, 2013 | 11:55 AM
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Re: quick backspacing question

BS from 5.25 to 5.4" will work all around - anything more and you risk hitting the tie rod ends. Unless you have a BBK that moves your track out in the front, 5.5" BS will most likely require at least a thin spacer.
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Old Aug 8, 2013 | 11:30 AM
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Car: 1987 Camaro Z28
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Axle/Gears: 4th gen 10 bolt 3:73 Richmond gears
Re: quick backspacing question

im looking at 17x11 american racing torque thrust II wheels for all four corners. im getting fender flares that add 1.5 inches out. since you can run 9.5 inch wheels factory with no problems or tucking issues, im just gonna add 1.5 inches to that and thats where i get the 11 from. im getting alot of numbers, but i need exacts front and rear. whats the max bs rear
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Old Aug 8, 2013 | 11:33 AM
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Car: 1987 Camaro Z28
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Transmission: Borg Warner T56
Axle/Gears: 4th gen 10 bolt 3:73 Richmond gears
Re: quick backspacing question

actually, whats the backspacing of the firehawk rims, they are 17x9.5, i can use that backspacing and just get that in 11 inch wide AR rims
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Old Aug 8, 2013 | 01:15 PM
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Re: quick backspacing question

I have Torq 17 x 9.5" in front and 17 x 11" in rear and done extensive searching for this.

My fronts have 5" backspacing and it's a perfect fit with 275 tires. Any more backspacing and you hit the tie rod end.

My rears have 5.5" backspacing and while it clears everything in the inner fender, the 315 tires stick out of the fenders. If you want to tuck the 11 inch wheels inside the fender you need 6.5" - 7.0" backspacing and you will have to mod your inner fenders. There are many posts on this with pictures.

If you added 1.5" flares, a 5.5" backspacing 17x11 rim on the rear would work well for you. I'm pretty sure you will have issues with a front 17 x 11" rubbing badly at full lock. My 17 x 9.5" rub lightly at full lock.
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Old Aug 8, 2013 | 06:09 PM
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Car: 1987 Camaro Z28
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Axle/Gears: 4th gen 10 bolt 3:73 Richmond gears
Re: quick backspacing question

ill have the 1.5 inch flares on the front too. and thank you very much for the detailed info.
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Old Aug 8, 2013 | 10:36 PM
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From: Sparta, NJ
Car: 1987 Camaro Z28
Engine: Carbed 355
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Axle/Gears: 4th gen 10 bolt 3:73 Richmond gears
Re: quick backspacing question

89******bird, what is the tire size and brand of your rear tires, 315/__r__
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Old Aug 13, 2013 | 11:02 PM
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Re: quick backspacing question

6.25 is the max without massaging.
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Old Aug 14, 2013 | 03:33 PM
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Re: quick backspacing question

haha it sensored the word m u l l e t
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Old Sep 2, 2013 | 03:58 PM
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From: Sparta, NJ
Car: 1987 Camaro Z28
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Transmission: Borg Warner T56
Axle/Gears: 4th gen 10 bolt 3:73 Richmond gears
Re: quick backspacing question

my car has 16x8 torque thrusts with 3.75 inch backspacing. so does that mean if i g0 6.25 backspacing, which is the max backspacing before any modification, that i can run 10.5 inch wide wheels? the 16x8's sit flush in the wheel well right now.
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Old Sep 2, 2013 | 04:33 PM
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Re: quick backspacing question

Originally Posted by mac86
my car has 16x8 torque thrusts with 3.75 inch backspacing. so does that mean if i g0 6.25 backspacing, which is the max backspacing before any modification, that i can run 10.5 inch wide wheels? the 16x8's sit flush in the wheel well right now.
Yes in the rear.
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Old Sep 2, 2013 | 05:33 PM
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Re: quick backspacing question

With 10.5" you may rub the outer fender lip. I have 10" wheels with 285 tires with 6.2" backspacing and it barely clears the fender lip.
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Old Sep 2, 2013 | 06:57 PM
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Re: quick backspacing question

Originally Posted by 89******bird
With 10.5" you may rub the outer fender lip. I have 10" wheels with 285 tires with 6.2" backspacing and it barely clears the fender lip.
That's why you want the wheel as far as inward as possible without rubbing.
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Old Sep 2, 2013 | 06:59 PM
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Re: quick backspacing question

Agreed. But to fit a 10.5" wheel inside the fender you will need about 6.5" backspacing, which will require some inner fender mods. 10" is about the widest you can fit without any modding. (in my opinion, but there are many on this topic)
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Old Sep 2, 2013 | 07:13 PM
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Re: quick backspacing question

Originally Posted by 89******bird
Agreed. But to fit a 10.5" wheel inside the fender you will need about 6.5" backspacing, which will require some inner fender mods. 10" is about the widest you can fit without any modding. (in my opinion, but there are many on this topic)
That may be true. And it also depends on which lower control arms you have on your car. Some are wide, narrow and between. I think with a 295/35/18 tire may rub more than a 285/35/18.
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Old Sep 2, 2013 | 09:37 PM
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From: Sparta, NJ
Car: 1987 Camaro Z28
Engine: Carbed 355
Transmission: Borg Warner T56
Axle/Gears: 4th gen 10 bolt 3:73 Richmond gears
Re: quick backspacing question

wait, but i have 8 inch wide wheels on it right now, and they have a 3.75 inch backspacing on them. max backspacing without any mods is 6.25 inches. 6.25-3.75= 2.5 inches. 8+2.5 is 10.5 so if my math is correct, it will fit in the fender well without any mods with a 6.25 inch backspacing

also, my wheels right now are flush with the outer fender lip, not the inner lip that folds in, beyond that. im going to roll my fenders in the rear so it wont rub the lip

Last edited by mac86; Sep 2, 2013 at 09:41 PM.
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