backspacing help

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Jun 4, 2015 | 10:58 PM

newc3

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backspacing help

going to order torq thrust II wheels, 15x8's. the backspace is either 4.50 or 3.79 which backspace should I get?

have 255/60r15 tires on the front and 275/60r15 tires on the back

78 vette

Jun 4, 2015 | 11:09 PM

GaToy

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From: Fort Valley Georgia

The 3.79 would stick out more but you wouldn't have any problems with the parking brake brackets.

Jun 5, 2015 | 12:37 AM

cagotzmann

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Quote:

Originally Posted by newc3

going to order torq thrust II wheels, 15x8's. the backspace is either 4.50 or 3.79 which backspace should I get?

have 255/60r15 tires on the front and 275/60r15 tires on the back

78 vette

Neither stock 15x8 wheel is 4" Backspace. I have seen people claim they have those wheels with 4" backspace.

One will sit in too far and need an adapter to move the wheel out, the other will stick out.

4" backspace on the 15x8 is -12mm offset.

Jun 5, 2015 | 01:06 AM

newc3

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just not sure which wheels to order. those were the 2 choices

Jun 5, 2015 | 02:31 AM

TCracingCA

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a number of things would need to happen to run 4.5 related to clearance

the 275 on a stock fender is pushing it on a 3.75 rim

Jun 5, 2015 | 12:25 PM

The Punisher

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C3 of Year Finalist (appearance mods) 2019

If you go with the 4.5 you will have to relocate the emergency brake brackets that holds the cable. And also with a 275 tire you still may need a wheel spacer of about 5/16". Then with adding the spacer its quite possible you will need longer wheel studs depending on the wheel design.

I went with a 17" torque thrust 2 with a backspace of 4.07". didn't require any modifications

Last edited by The Punisher; Jun 5, 2015 at 12:34 PM.

Jun 5, 2015 | 12:34 PM

newc3

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It sounds like going with the 3.79 would be easier, I don't mind if it sticks out! I think I'll measure the stock wheels and what the back spacing is now

Jun 5, 2015 | 12:37 PM

newc3

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And a 255 and a 275 tire can go on a 15x8 wheel?

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Jun 5, 2015 | 02:35 PM

red topless gator

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Quote:

Originally Posted by The Punisher

Same thing here

Jun 5, 2015 | 02:53 PM

#10

ddawson

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From: Lincoln, CA

You want a 4" backspace or -12MM offset.

Jun 5, 2015 | 11:46 PM

#11

newc3

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well they only had 4.50 and 3.79 so I went with the 3.79, hope it works out

Jun 6, 2015 | 05:01 AM

#12

The Punisher

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If you get a tire like a 235 it won't over hang the rim and may be closer to the edge of the wheel well. Just guessing Good luck

Jun 6, 2015 | 04:42 PM

#13

The13Bats

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From: Eustis ( Area 51 Bat Cave ) Fl

Quote:

Originally Posted by newc3

well they only had 4.50 and 3.79 so I went with the 3.79, hope it works out

It will...

Jun 6, 2015 | 10:14 PM

#14

newc3

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Thanks guys

Jun 11, 2015 | 09:18 PM

#15

newc3

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well I placed an order at Tdot last thursday for the wheels, got an email sunday saying they have to contact american racing 1st thing monday to "check for proper fitment" on my vehicle.

Haven't heard anything since, and no response to emails... think I just got screwed