Wheel and Tire help

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SRT_DSTRHOLC

SRT_DSTRHOLC

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Hey guys im interested in possibly going to 18in wheels all around, but I need help . I have a b body rear end that has not been shortened and is about 1.5in longer than an A body rear on each side. I want to use a 18x 8.5 wheel in the rear if possible and as big of tire as possible. In the front I want to run the same if possible. Do you guys think I could do this with the right offset? Thanks guys the wheels will be like this

http://www.popularhotrodding.com/features/0903phr_1971_dodge_demon/index.html

Thanks guys
 
You've got two actions running here. First is using the B-body axle. The second is using 18 inch wheels.

The B-body axle is at least 1.375 inches longer drum to drum.

http://www.moparts.org/Tech/Archive/axle/17.html

The B-body spring perches are one inch farther apart than the A-body. They will need to be carefully removed and re-welded in the proper location.

Regarding the wheels, I spoke with Stockton Wheel, a long time ago, who told me the largest wheel/tire package that will fit within the A-body wheel well is a 235/60-15. That equates to 26.1" diameter and 9.5" width. If you can come up with an 18" wheel/tire package that will fit that criteria, you should be good to go.
 
235/40-18 is close.. I found as the sidewall ratio goes down the tread is wider because it's more squared.
 
I have 17x9" rear wheels with 275/40x17 tires and 17x7" front wheels and 215/45x17 tires. The bs on the rear wheels is 5" front is 4" I also have an A-Body 8.75 rear. I had to bend the rear wheel lip up a tad but it is not noticable. You may need at least 5.5" of bs to make 18x8.5 wheels work with a B-Body rear.
 

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2 Darts said:
You've got two actions running here. First is using the B-body axle. The second is using 18 inch wheels.

The B-body axle is at least 1.375 inches longer drum to drum.

http://www.moparts.org/Tech/Archive/axle/17.html

The B-body spring perches are one inch farther apart than the A-body. They will need to be carefully removed and re-welded in the proper location.

Regarding the wheels, I spoke with Stockton Wheel, a long time ago, who told me the largest wheel/tire package that will fit within the A-body wheel well is a 235/60-15. That equates to 26.1" diameter and 9.5" width. If you can come up with an 18" wheel/tire package that will fit that criteria, you should be good to go.[/QUOTE

I have 28in on there already.... on 15x8..Already..
Click to expand...
 
18x8.5" is doable all the way around, even 18x9" is doable all the way around. The problem is going to be using the same offset.

The B-body rear helps, but to maximize tire size up front you'll want around 6.3-6.4" of backspace. That should let you run a 275 up front. But to get the 275 out back you're only going to want about 6" of backspace, even with the B rear. So, to run the same offset you'd have to think about spacers out back. 1/4" is about as big of a spacer as you want to run, unless you're talking about the spacers that include a new set of studs. But those only come in 1" or bigger. So...

6.25" backspace is probably the answer. Should be enough to get 275's in the front, and you can run a 1/4" spacer out back if you need to.

Do you have the 1/2" hanger/shackle spring offset on that B rear? That could be the other answer. I know of a Demon with a B rear running 18x9's, 6" backspace, and 275/40/18's with the springs at 43". Move them to 42" and you can make that 6.3-6.4" offset work all the way around...
 
Subscribed, thanks. Good project. Same boat I am in. Looking at approx 6 inch bs (18 x 9). Interested in identical wheels and tires 275/40r18 (for rotate and spare) all four corners.
 
72bluNblu said:
18x8.5" is doable all the way around, even 18x9" is doable all the way around. The problem is going to be using the same offset.

The B-body rear helps, but to maximize tire size up front you'll want around 6.3-6.4" of backspace. That should let you run a 275 up front. But to get the 275 out back you're only going to want about 6" of backspace, even with the B rear. So, to run the same offset you'd have to think about spacers out back. 1/4" is about as big of a spacer as you want to run, unless you're talking about the spacers that include a new set of studs. But those only come in 1" or bigger. So...

6.25" backspace is probably the answer. Should be enough to get 275's in the front, and you can run a 1/4" spacer out back if you need to.

Do you have the 1/2" hanger/shackle spring offset on that B rear? That could be the other answer. I know of a Demon with a B rear running 18x9's, 6" backspace, and 275/40/18's with the springs at 43". Move them to 42" and you can make that 6.3-6.4" offset work all the way around...
Click to expand...

I won't be running 275 up front... The wheels I want would be 18x9.5 in rear with 6in BS.. Tires I was thinking 255/55/18 or 275/50 or 305/40..The front wheels would be regular 18x8s. At most I will relocate the springs fully. That will be fine because I plan on going 4 link in future. I just don't want to cut the tubs, but I do want to tuck the tops of the tires all the way around.

I would love the look of the red chevelle, but would be happy with the look of the orange one, meaning the way the wheels are slightly tucked.
 

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Rice Nuker said:
Subscribed, thanks. Good project. Same boat I am in. Looking at approx 6 inch bs (18 x 9). Interested in identical wheels and tires 275/40r18 (for rotate and spare) all four corners.
Click to expand...

I really think that in order to clear a 275 up front you need a little more than 6" to keep it out of the fenders. Especially with a 275/40/18, as that's a pretty tall tire for the front.

With a B body rear and a 1/2" spring relocation I think you can pull off the same backspace front and rear with a 275 at around 6.3-6.4, which is a pretty common offset. It'd be close enough that if you had issues you should be able to use a hubcentric spacer for adjustments, nothing big.

Fst73_360 said:
I won't be running 275 up front... The wheels I want would be 18x9.5 in rear with 6in BS.. Tires I was thinking 255/55/18 or 275/50 or 305/40..The front wheels would be regular 18x8s. At most I will relocate the springs fully. That will be fine because I plan on going 4 link in future. I just don't want to cut the tubs, but I do want to tuck the tops of the tires all the way around.
Click to expand...

You won't fit a 305 into the stock wheel tubs. I'm pretty sure that even a 295 would be too much if you're lowered, the wheel tubs are too tapered. When I had the 275/40/17's on my Duster in the back they just barely fit, it would probably have needed a quarter lip trim for the street. A 1/2" offset buys you the rest of the wheel tub, but that doesn't get you a 295, the section with is over 3/4" wider.

Without a mini-tub, I think 285 is the best you can do unless the rear end is jacked up in the air. The spring offset or 4 link will only get you to the wheel tub unless you mini-tub it, and that means no 295's or 305's.
 
72bluNblu said:
I really think that in order to clear a 275 up front you need a little more than 6" to keep it out of the fenders. Especially with a 275/40/18, as that's a pretty tall tire for the front.

With a B body rear and a 1/2" spring relocation I think you can pull off the same backspace front and rear with a 275 at around 6.3-6.4, which is a pretty common offset. It'd be close enough that if you had issues you should be able to use a hubcentric spacer for adjustments, nothing big.



You won't fit a 305 into the stock wheel tubs. I'm pretty sure that even a 295 would be too much if you're lowered, the wheel tubs are too tapered. When I had the 275/40/17's on my Duster in the back they just barely fit, it would probably have needed a quarter lip trim for the street. A 1/2" offset buys you the rest of the wheel tub, but that doesn't get you a 295, the section with is over 3/4" wider.

Without a mini-tub, I think 285 is the best you can do unless the rear end is jacked up in the air. The spring offset or 4 link will only get you to the wheel tub unless you mini-tub it, and that means no 295's or 305's.
Click to expand...

Shoot..Okay well I would be happy with 285/50 is .70in wider than a 275/60/15.. That might work hmm, but I need at least a 28in tire as wide as possible and a 29 being great. I will be rolling the fenders also.
 
72bluNblu said:
I really think that in order to clear a 275 up front you need a little more than 6" to keep it out of the fenders. Especially with a 275/40/18, as that's a pretty tall tire for the front.

With a B body rear and a 1/2" spring relocation I think you can pull off the same backspace front and rear with a 275 at around 6.3-6.4, which is a pretty common offset. It'd be close enough that if you had issues you should be able to use a hubcentric spacer for adjustments, nothing big.



You won't fit a 305 into the stock wheel tubs. I'm pretty sure that even a 295 would be too much if you're lowered, the wheel tubs are too tapered. When I had the 275/40/17's on my Duster in the back they just barely fit, it would probably have needed a quarter lip trim for the street. A 1/2" offset buys you the rest of the wheel tub, but that doesn't get you a 295, the section with is over 3/4" wider.

Without a mini-tub, I think 285 is the best you can do unless the rear end is jacked up in the air. The spring offset or 4 link will only get you to the wheel tub unless you mini-tub it, and that means no 295's or 305's.
Click to expand...

Do you think its possible to cut the bottom of the inside wheel well and just stretch it? And then weld a small piece in to close it off? 295/45/18 looks like the goal tire as they are cheaper than 285/50s

My current 275/50/15 are 11in section width and the 295/45/18 are 11.5 wide for nitto tires. At most I think I would have to move the springs in.
 
Fst73_360 said:
Do you think its possible to cut the bottom of the inside wheel well and just stretch it? And then weld a small piece in to close it off? 295/45/18 looks like the goal tire as they are cheaper than 285/50s

My current 275/50/15 are 11in section width and the 295/45/18 are 11.5 wide for nitto tires. At most I think I would have to move the springs in.
Click to expand...

The tubs are only as wide as the springs with a 1/2" offset. And, stretching the bottom isn't going to cut it unless you sit WAY high in the back, especially with a 28" tire. The tubs taper up, so they get even smaller than they are at the springs. At their widest, the tubs are only 11.5" wide. Even with a fender roll, I seriously doubt you'll get enough clearance for a 295 without rubbing on the springs and quarters without a 3" relocation and a mini-tub.
 
72bluNblu said:
The tubs are only as wide as the springs with a 1/2" offset. And, stretching the bottom isn't going to cut it unless you sit WAY high in the back, especially with a 28" tire. The tubs taper up, so they get even smaller than they are at the springs. At their widest, the tubs are only 11.5" wide. Even with a fender roll, I seriously doubt you'll get enough clearance for a 295 without rubbing on the springs and quarters without a 3" relocation and a mini-tub.
Click to expand...

Just talked to JimmyRay
http://www.forabodiesonly.com/mopar/showthread.php?t=130381
He is running 295/45/17 on his duster. Stock springs, stock tubs and stock length Dana sent me this in a PM "I have a STD width Dana rear, stock spring locations. The 275's fit easily but the 295 are about 1/8" from the spring. 17x8 wheels, 4.5" backspace."
 
72bluNblu said:
The tubs are only as wide as the springs with a 1/2" offset. And, stretching the bottom isn't going to cut it unless you sit WAY high in the back, especially with a 28" tire. The tubs taper up, so they get even smaller than they are at the springs. At their widest, the tubs are only 11.5" wide. Even with a fender roll, I seriously doubt you'll get enough clearance for a 295 without rubbing on the springs and quarters without a 3" relocation and a mini-tub.
Click to expand...

Also I believe cracked told me that there is 12.5inches of space from inner tup to Lip.. And there is about 11in from spring to lip.. I can get .50in more room by cutting the lip. The 295 is 11.5 wide (section width) on a 9.5 minimum wheel.

Also not arguing with you, just trying to get you to see that MAYBE it is possible, especially if JimmyRay is running a STOCK width rear and I have 2in more space.
 
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