some 4/6 drop wheel help (yea i know)

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smoothandlow84

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Stay a way from using those 1/4" spacers...just buy the correct offset wheels and or go with a larger diameter wheel. Those spacers are dangerous, in fact most reputable tire shps won't reinstall wheels if those have been previously installed. You coukd use stud adapters instead, but then again you will be limited to the width of the front tubs. Have you considered narrower control arms? I dont understand the hate of using 20" wheels. Tires for 20" wheels are far easier to source that 17, or 18". Backspacing is obviously the critical issue here and if you insist on staying with a 15" wheel...dig deeper into your wallet and invest in shortened tubular control arms. Strong arm control arms make a nice setup. You may also look into Ride Tech. Google search.....
 

TravisB

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Stay a way from using those 1/4" spacers...just buy the correct offset wheels and or go with a larger diameter wheel. Those spacers are dangerous, in fact most reputable tire shps won't reinstall wheels if those have been previously installed. You coukd use stud adapters instead, but then again you will be limited to the width of the front tubs. Have you considered narrower control arms? I dont understand the hate of using 20" wheels. Tires for 20" wheels are far easier to source that 17, or 18". Backspacing is obviously the critical issue here and if you insist on staying with a 15" wheel...dig deeper into your wallet and invest in shortened tubular control arms. Strong arm control arms make a nice setup. You may also look into Ride Tech. Google search.....

For me anyway it's the added cost. If the 15s I already own will fit I am going to run them. If they don't I will be shopping for wheels.
 

86Peter454

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Stay a way from using those 1/4" spacers...just buy the correct offset wheels and or go with a larger diameter wheel. Those spacers are dangerous, in fact most reputable tire shps won't reinstall wheels if those have been previously installed. You coukd use stud adapters instead, but then again you will be limited to the width of the front tubs. Have you considered narrower control arms? I dont understand the hate of using 20" wheels. Tires for 20" wheels are far easier to source that 17, or 18". Backspacing is obviously the critical issue here and if you insist on staying with a 15" wheel...dig deeper into your wallet and invest in shortened tubular control arms. Strong arm control arms make a nice setup. You may also look into Ride Tech. Google search.....

style mostly. i dont like the look of 20" wheels for my truck. i like the look of the tire sidewall.

anyway to share what i have found at this point.

i got the front suspension bits replaced over the weekend. thats the bushings(aside from passenger side because lower control arm was dicked), ball joints, outer tie rod ends, 2.5" mcgaughys drop spindles, and moog 6454 HD springs with half a rung cut off to start with. oh and also beltech struts.

i threw up my new wheels with no tires on just to check some back space clearance and a little bit of fender clearance. these where 15x7 with 3.75" backspace.

then i threw up the wheels that where on it that at 15x8 with 3.75" of backspacing. these fit just fine and looks like even plenty of fender clearance with the right tire. (im still glad im going with 7in in front and 8 inch in back to help get the track width closer to even.) i did have some places with issues though...

the steering arm on the spindle hits the wheel weight on the driver side and just clears on the passenger side. i could grind a but on the steering arm to make the wheel weight clear or i could run sticky weights on the new wheels. if im going to run sticky weights i am going to have to grind some on the caliper to ensure they will clear. so either way some slight grinding will be required.

here are some picks of the lower control arm clearance and steering arm clearance. again this is with 3.75" of backspacing.
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i turned the wheels lock to lock and they dont hit the lower control arm at all.

the truck will get lowered more up front by cutting more of the spring so i will be keeping an eye on this clearance and see if it decreases.

but with that as far as i can tell 3.75" backspacing works just fine with 2.5" drop spindles. some small grinding may be necessary but not in support areas that may cause issues. also im working with aluminum wheels here its possible steel will have different clearance due to material thickness and such. ill keep this post updated as i drop the ass end and drop the front further and after i get my new wheels put on.

here is a pic of the truck after the drop. lol you can barley tell. though once the springs settle a bit it will keep going down. it has already settled half and inch since i installed them. and if the back end is lower (it likely will be) ill be cutting more spring till i get the drop close to where i want it.

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86Peter454

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so we got the back end lowered. (idk if i should keep posting in this thread or not but i figured some of this info may help others)

the front needs to come down more still. though it has settled around 3/4 of an inch just sitting around. but still needs about another inch of low.

played hell with some of the DJM flip kit parts mostly the shock extender bits.

this is the only pic i have of the truck now. ill have videos up soon about the process and stuff. also will get more pictures next week probably.

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Scott91370

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so we got the back end lowered. (idk if i should keep posting in this thread or not but i figured some of this info may help others)

Please, post up some more!!
I'm in the process of putting together an 82 with McGaughy's 2.5" spindles and 2" springs with a rear flip. I'll be going with a larger wheel so I am not worried about rubbing but would like to see the back space, tire size and how it looks in the fenders.
 

Brads74

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I’m currently looking to do a 4/6 drop on my 74 c15 and wanna go with 15x8 on the front. The backspacing says 3.75. I’ve been up and down the interwebs trying to figure out if those will stay clear of the arms. Any insight here?
 

mlsceo

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On my truck with 2-1/2" drop spindles the 15" factory wheel just clears the steering knuckle. Backspace is 3-1/2". 3-3/4" backspace would probably fit with a little trimming on the knuckle. 4" won't fit with a 15" wheel.
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mlsceo

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Please, post up some more!!
I'm in the process of putting together an 82 with McGaughy's 2.5" spindles and 2" springs with a rear flip. I'll be going with a larger wheel so I am not worried about rubbing but would like to see the back space, tire size and how it looks in the fenders.
These rears are 15x10 with a 4-1/2" backspace. I used the same McGaughys parts you are planning to use. There was no way I had frame clearance without the C notch.
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mlsceo

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Something else to think about. The 2" drop springs have settled a bit and the top of my tire is rubbing the inner fender well over bumps. It's a 28" diameter tire. I bought some 5/8" spring spacers in case the rubbing gets worse but as of now it's not enough to make me want to change the rake, which I really like.
 

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