Spring relocation without mini tub?

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gumper

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Going to be cutting my car apart tomorrow to move the springs in, and was going to do a mini tub job. The tire size I want to run is 28x10.5x15 bias drag slicks with 15x10 wheels. Figured a backspace of 5.5" would work without narrowing my rear end. I was looking at how it's set up now though, and I have at least 1 1/4" clearance between the stock tubs, and my 28x9 slicks with 15x8 wheels with 4.625 backspace and 1/4" spacers. Think I can fit the 10.5 slicks with just the spring move? Would I want to do a different backspacing?
 
Im not sure what year and model your cars is but on my 66 dart I had to go with a 6.5 backspace and mini tub along with the springs moving in. Im sure others will chime in. Best of luck
Rod
 
70 Duster. I elected to have more backspace in order to keep the tires more inside the body. I think it would work with a ~4.5" backspace, but that'd stick the sidewall out to near flush with the body.
 
I'm trying to visualize it. The 28x10.5 tires width dimensions are 10" tread width and 12" section. The 28x9 I run now are 8.6" tread and 10.8 section. That would mean the overall width is .6" wider on each side. With 4.5" backspace without spacers the tires should stick out roughly 1/2" further than they do now which is OK. It also lets me get away with not cutting. Is my math off? If I ran the 5.5" backspace then the tires would stick in 1/2" more than they are now. Not sure how that would look.
 
Well I'm sure you can make that work.
But mini-tubbing and spring into-the-frame is a huge amount of work, just to avoid narrowing the rear.
After doing all that, I would be wanting to fill those new tubs up, with like 325s. And that would require narrowing the rear anyway, or another set of custom wheels.
So it seems to me,that if you just get the springs outta the way,pull the rear end out,Get a set of off the shelf 10" wheels with a 4.5bs, and narrow the rear to fit those, then you will be all set for whatever wheels you like. The 4.5 used to be a very common bs.
BluNblue has stated many times that 275s fit back there. He did the homework for you. 275s are 10.8section on 8s. The 60s are 28 tall.I have had those 275/60-15s on 8.5s, in my stock Barracuda tubs. Miles of room.
I've put 10 inch 5.5bs wheels in there, and IMO it looks awful; but that is an opinion. I still have those wheels. But I paid a wheel company to move the centers in for a 4.5 bs, lol, after I narrowed the rear.Now they look OK,IMO.lol.
 
I don't need anything wider. That just adds weight and drag. Right now it hooks good on 9" tires until the sun goes down with cool temps. Then it starts getting squirrelly which causes lost races. If I ever decide I need big big tires then I'll 4 link it and get rid of the 8 3/4 anyway.

I actually had 275/60s on it without moving the springs. The 15x8 wheels with 4.625 bs and 1/4" spacer gave me just enough clearance.
 
I did the spring relocation & the mini tub, but I'm running 18" x 10" rims with a 6.5" back spacing and they barely clear the inner lip on the quarter panel. I had to remove a 1/4" or more of the inner lip to help with the clearance issues.
 
I did the spring relocation & the mini tub, but I'm running 18" x 10" rims with a 6.5" back spacing and they barely clear the inner lip on the quarter panel. I had to remove a 1/4" or more of the inner lip to help with the clearance issues.
What size tires, and is it lowered?
 
It's been 12+ years ago, but I had 10.5" slicks under my car with the 3/4" offset kit. I think they were 29.5", or 28.5" at the least. They also may have been on 11" rims. The tread was just inside the cut/rolled fender lip but the section width did stick out. I don't recall offsets or the clearance to the inner fender lip. I have 9" slicks now, on 10" rims.

Mini-tubbing with the OEM sheetmetal and adding a strip in the middle after splitting the tub would save some work over new tubs.
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myron2.jpg
 
71 Dart. Moved springs in and mini tub. I cut 3" off each side of rear-end. I am running 28"x12"x15" MT on 15"x10" 5.5" BS. I have about 3/4" to outer fender and 1 3/4" to inner fender/frame. If I could get another 1/2"- 3/4" space in there I could run 28"x15"x15" MT's. Good luck.
 
Locomotion, you happen happen to remember the wheel backspace?
 
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I don't remember what the backspacing was on the previous 11" rims, but they may have been the same or +1" as the current 10" wide wheels. The Holeshot wheels on the car now have a 4 7/8" backspacing. (Their wheels normally come in 1" increments: i.e.: 3 7/8", 4 7/8", 5 7/8", etc.) but they may have ways for some adjustments.

* Overall section width as mounted is 12 1/4" with the current 10" rims and 9" Hoosier radial slicks.

* I have roughly 1" clearance to the leaf springs and roughly 1 1/2" clearance to the inner wheel well lip. I have the Mopar offset kit (Had to cut a hole in the frame rail for bolt clearance & installation.) Don't know if other brands may be off a bit in actual measurements.

* There is at least a good inch from the tread width to the cut/rolled outer fender lip. But if the car sat 2-3" lower, the sidewall would touch.

17343073_1413085505422959_1107167682191961593_n.jpg
 
The rear is standard A-body 8 3/4" housing with non-adjustable bearings & E/B body drum brakes.
 
I'm out of town right now, so I can't access my pics, but no need to minitub to run the size tires you mentioned. I ran a 71 Duster with a B-body axle, 3/4" spring relocation kit with 28 X 10.5 X 15 on 10" Welds with no rubs without any tub modifications. With the right backspacing anything is possible.
 
Happen to know your backspace Brad? I'd like to keep the tires from sticking out far. Not a fan of the bulge.
 
Happen to know your backspace Brad? I'd like to keep the tires from sticking out far. Not a fan of the bulge.
It was 6.5" backspacing, but once again, that was a B-body width axle, I believe from a 69 B-body.
 
3" wider overall so 1.5" on each side. 5.5" bs may be too close on the inner. Any idea how much room you have on the inside?
 
As another data point, my '72 Dart shell came with minitubs and a B-body rear hung under it. I got a deal on some widened 15x10 steelies with an 8" backspacing. So I had the housing trued (it was WAY off) and narrowed to stock A-body width by Moser. Fits great with 295/50 tires and from the side is very low-key appearing :)
 
As another data point, my '72 Dart shell came with minitubs and a B-body rear hung under it. I got a deal on some widened 15x10 steelies with an 8" backspacing. So I had the housing trued (it was WAY off) and narrowed to stock A-body width by Moser. Fits great with 295/50 tires and from the side is very low-key appearing :)
Pictures?
 
3" wider overall so 1.5" on each side. 5.5" bs may be too close on the inner. Any idea how much room you have on the inside?
It has been years since that car sold, but I believe it was just over an inch on the inside. I had SS springs in the rear so it sat pretty high.
 
What size tires, and is it lowered?
275/35/18 tires on the rear, stock width A-Body 8 3/4 rear end, no lowering blocks with disc brakes, US Car Tool spring relocation kit which has 3 hole locations on the front spring mount, I have the drivers side spring in the top hole and the passenger side spring in the middle hole, I believe the rear shackles are 3 1/2" or 4". Wheels are custom made 18" x 10" with 6.5" back spacing.
 
Pictures?
Lots of room, 295/50-15 on 10" rim, 8" backspacing, with mini-tubs. A 325 would have fit but would be close on the inside. I decided not to push it for that last inch of section width and didn't want to use spacers.
Dart exhaust (6).JPG
Dart exhaust (7).JPG
fit but would be close on the inside. I decided not to push it for that last inch of section width.
 
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