Backspacing help

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Soundmound

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So I ordered 20 x 8.5 w/ 4.5 backspacing and now am a little panicked. Doing a 4/6 static drop(spindles/springs & flip) in the future with what I assume will be stock track width front and rear. Am I going to rub control arm or fender? I've called all the "experts" at the spindle and wheel company and they are all non-commital and the answer changes. I just need a clear answer on should I stay with 4.5 or move to 5.25 backspacing. Help!
 

TotalyHucked

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Nah, you should be fine. My fronts are 20x8 with a 4.54" backspace. You *might* need to roll you fender lip up a touch but at 4" you'll likely be ok. I'm somewhere around 5-5.5" up front. The 5.25" would be more flat faced. What wheels did you order? I'm curious as to what the offset and everything is as well.

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Soundmound

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The Sprint 20" x 8.5" w/ 4.5" backspacing. I measured rotor face to inner fender contact point at 10.75" and rotor face to outer fender lip at 6". There's a middle ground backspacing 4.75" available also.
 

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Nah, you should be fine. My fronts are 20x8 with a 4.54" backspace. You *might* need to roll you fender lip up a touch but at 4" you'll likely be ok. I'm somewhere around 5-5.5" up front. The 5.25" would be more flat faced. What wheels did you order? I'm curious as to what the offset and everything is as well.

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The Sprint 20" x 8.5" w/ 4.5" backspacing. I measured rotor face to inner fender contact point at 10.75" and rotor face to outer fender lip at 6". There's a middle ground backspacing 4.75" available also.
 

TotalyHucked

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The Sprint 20" x 8.5" w/ 4.5" backspacing. I measured rotor face to inner fender contact point at 10.75" and rotor face to outer fender lip at 6". There's a middle ground backspacing 4.75" available also.
Idk if you saw this on their site:

"Recommendations for C10: The 5.25" backspacing front wheels fit trucks with the factory-track width front suspension The 4.5" and 4.75" backspacing front wheels are optimized for narrowed front spindles (common on lowered applications such as CPP spindles - this also gives the wheel a deeper dish). The 5.5" backspacing fit rear wheels with factory-length axles. The 4.0" backspacing fit rear wheels on rear axles that have been narrowed 1.5" per side (3" total).

Staggered Diameter and Width: 19x8.5 (4.75" backspacing) Front Wheels with 20x10 (5.5" backspacing) Rear Wheels Fitment Optimized on the C10 Trucks - Lowered Vehicles with Narrowed Front Spindles and Factory Width Rear Axle Recommended Tires for a "Meaty" Fitment: 255/45R19 and 275/50R20 Choose from MAG7, Anthracite, or Polished Finish

20" with Staggered Width: 20x8.5 (4.75" backspace) Front Wheels with 20x10 (5.5" backspace) Rear Wheels Fitment Optimized on the C10 Trucks - Lowered Vehicles with Narrowed Front Spindles and Factory Width Rear Axle Recommended Tires for a "Meaty" Fitment: 255/45R20 and 275/50R20 Choose from MAG7, Anthracite, or Polished Finish"
 

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The Sprint 20" x 8.5" w/ 4.5" backspacing. I measured rotor face to inner fender contact point at 10.75" and rotor face to outer fender lip at 6". There's a middle ground backspacing 4.75" available also.
I just googled that wheel and got like 30 "sprint" wheels. Too ambiguous, you need to spit out some more information there buddy. :cool:
 

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Here's a good thread that talks about spindles as well. You'll have choices of spindle when it's time to buy. Either stock width, slightly wider (most traditional drop spindles are these, roughly .250" increase per side) or narrower spindles like the CPP Modular.

 

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Idk if you saw this on their site:

"Recommendations for C10: The 5.25" backspacing front wheels fit trucks with the factory-track width front suspension The 4.5" and 4.75" backspacing front wheels are optimized for narrowed front spindles (common on lowered applications such as CPP spindles - this also gives the wheel a deeper dish). The 5.5" backspacing fit rear wheels with factory-length axles. The 4.0" backspacing fit rear wheels on rear axles that have been narrowed 1.5" per side (3" total).

Staggered Diameter and Width: 19x8.5 (4.75" backspacing) Front Wheels with 20x10 (5.5" backspacing) Rear Wheels Fitment Optimized on the C10 Trucks - Lowered Vehicles with Narrowed Front Spindles and Factory Width Rear Axle Recommended Tires for a "Meaty" Fitment: 255/45R19 and 275/50R20 Choose from MAG7, Anthracite, or Polished Finish

20" with Staggered Width: 20x8.5 (4.75" backspace) Front Wheels with 20x10 (5.5" backspace) Rear Wheels Fitment Optimized on the C10 Trucks - Lowered Vehicles with Narrowed Front Spindles and Factory Width Rear Axle Recommended Tires for a "Meaty" Fitment: 255/45R20 and 275/50R20 Choose from MAG7, Anthracite, or Polished Finish"
I did that's part of the issue. When I talked to them the answer changes dependingon the support person. I know I'll need a spacer in the rear with a square(all 4 the same) setup at 4.5" BS. Most of the lowering spindles move track width out a hair except CPP which brings it in. Knowing I'd prefer to keep track width the same and will use a stock width rear axel, I'm thinking I should have gotten the 5.25" BS....
 

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I just googled that wheel and got like 30 "sprint" wheels. Too ambiguous, you need to spit out some more information there buddy. :cool:
 

TotalyHucked

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I did that's part of the issue. When I talked to them the answer changes dependingon the support person. I know I'll need a spacer in the rear with a square(all 4 the same) setup at 4.5" BS. Most of the lowering spindles move track width out a hair except CPP which brings it in. Knowing I'd prefer to keep track width the same and will use a stock width rear axel, I'm thinking I should have gotten the 5.25" BS....
Personally, I'd rather have the 4.5 so I'd have more dish to the wheel and get a spindle that narrows the track width if need be. Curious why you bought a square setup instead of staggered? The rear is going to look a little funny with narrow wheels. You should at least put a meatier tire back there IMHO
 

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Juicy. I love Halibrands. Gonna look sweeeeet!
 

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Personally, I'd rather have the 4.5 so I'd have more dish to the wheel and get a spindle that narrows the track width if need be. Curious why you bought a square setup instead of staggered? The rear is going to look a little funny with narrow wheels. You should at least put a meatier tire back there IMHO
Because the 10" width was no longer available... I even tried to substitute a spinner version but didn't want the alignment hole in the face. At least I can rotate them and have "even" wear...
 

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I did that's part of the issue. When I talked to them the answer changes dependingon the support person. I know I'll need a spacer in the rear with a square(all 4 the same) setup at 4.5" BS. Most of the lowering spindles move track width out a hair except CPP which brings it in. Knowing I'd prefer to keep track width the same and will use a stock width rear axel, I'm thinking I should have gotten the 5.25" BS....
IMHO, since you are buying 20" wheels...You are better off with the CPP modular spindles and get wheels that will work for them. The modular spindles allow for bigger brakes in case you upgrade and the X10 is designed for big wheels and brakes with a bolt-on hub.
 

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Zero desire to big brake upgrade. I would have to swap to factory 1.25 rotors and calipers to use CPP modular spindle.
 

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