Possible SBP to LBP adapter group buy?

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michiganpat

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Hi all,

After rebuilding my front suspension and upgrading my drum brakes to '73 up discs, to get my car to a single bolt pattern quickly, I've decided to just get adapters for my rear axle. I'll maybe look at a different rear axle this winter or further in the future. Looking at the options I've found on amazon, ebay, etc, I'm a little disappointed. most have a really large center bore (70-73MM) making them lug centric to the car, and taking a lot of meat out around the lug nuts (see image below). When I used bolt on adapters on my 5th ave as spacers to run mustang bullit wheels, the adapters were hub centric to the car, and I feel that is pretty important, especially given our cars only have 7/16" lug studs. the other crazy thing, is of the options I found, all but one used metric M12-1.5 studs instead of 1/2-20(?!).

On a weekend, I quick designed an adapter that would be hubcentric to the car as well as hubcentric to the wheel. I sent it to a machine shop I've worked with in the past for work to get a quote for 2, and they were quite expensive. I know with parts like this, piece price usually goes down with quantity, especially if he's developing a program for a CNC mill or lathe just for 2 of them. I've asked him how many he'd need to make to get them into the $80-100/pr range, told him of the potential market for a product like this, and if he'd be interested in doing a limited run. He's going to get back with me soon with what that number is. In the meantime, I got the OK from the administrator of the site to gage interest and see how many might be interested in a group buy.
1718724119764.png

here are the details:
they'd be machined from 6061 T6 aluminum.
they are 1" thick
lug nut pockets are 1.16" diameter (I measured my 3/4" impact socket, and it's 1.12" diameter, non impact 1/2" drive was 1.05")
I've designed it with a 59mm inside bore (2.323") to make them hubcentric to the car.
I currently have them designed with a 1/4" tall, 2.81" hub for the wheel (mopar size) so the wheels would be hubcentric to the adapter as well.
I was assuming just using the same studs the rear axle uses, so the stud holes/pockets are currently sized for these studs:
https://www.rockauto.com/en/moreinfo.php?pk=1060239&cc=1243178&pt=7680&jsn=850&optionchoice=0-0-1-1

would anyone be interested? if so, let me know either in PM, on this thread, or email me at [email protected] with the subject "FABO wheel adapters" so I see it easily in my flood of junk mail.

now some feedback I'd like from you guys in this thread:
1) would there be more interest to make the adapter hub ford sized, to make them hubcentric for those who want to using OEM or aftermarket wheels intended for mustangs? if so, can somebody verify the hub size? I think it's 70 or 70.5mm (2.756-2.776), but am not certain.
2) would you be OK with getting just the aluminum parts and a recommendation for wheel studs, or would you prefer to have them fully assembled with studs?
3) is there a different/better wheel stud? I found some other options under the generic section on rockauto that I was looking at, too, and may switch to these: https://www.rockauto.com/en/moreinfo.php?pk=9842748&cc=0&pt=7680.
4) would you want 7/16-20 lugnuts included to bolt to the car?
 
is there a different/better wheel stud?
My only thought would be screw in studs for the 1/2-20. Easy to find in different lengths.Depends on if the shop would want to instead of knurls.
I have a 72 Dart base Slant that is in the body shop for at least a year. Plan to do the disc swap up front.
Was going to start to look for the big bolt 7 1/4 or 8 1/4. But for $100 I'd run adapters on rear as the car will stay stock.
Plus it would help with the wider stance from the front disc swap. Even things out . My 2 cents.
 
Many people probably use adapters. Personally, I don't like the idea so I'm not a fan. Good luck though.
 
Any more than $100 a pair, and you'd be a good share of the way towards a set of Dr. Diff's 7.25 axles with true 5x4.5 bolt pattern and the correct center register; a much better solution.
Mopar Axle Pkg 7 1/4" A-Body 5X4 1/2" Bolt Pattern (pair)
I'm not a big fan of spacers/adapters either. If you're planning on running a big wheel/tire combo on the rear, you'll need more backspace with the adapters and then when you get a real bbp rear it could be too much and you may need to get different wheels again- negating any potential savings with the "temporary" spacer/adapter solution...
 
What kind of liability insurance will you have? Asking for a friend.
 
Any more than $100 a pair, and you'd be a good share of the way towards a set of Dr. Diff's 7.25 axles with true 5x4.5 bolt pattern and the correct center register; a much better solution.
Mopar Axle Pkg 7 1/4" A-Body 5X4 1/2" Bolt Pattern (pair)
I'm not a big fan of spacers/adapters either. If you're planning on running a big wheel/tire combo on the rear, you'll need more backspace with the adapters and then when you get a real bbp rear it could be too much and you may need to get different wheels again- negating any potential savings with the "temporary" spacer/adapter solution...
except his axles won't work with my 1976 SBP rear end, and you either have to buy different drums, or modify yours. it says that you can redrill your existing drums, but doesn't mention the drum center bore. if that's the case, then these axles wouldn't have the correct BBP register, as your existing drums center hole is 1/2" too small.....

at $300 for new 7.25" axle shafts ($420 with drums), you're WELL on your way towards a much more durable ford 8.8 axle, whether it's a direct pull out of a ranger or explorer, and if you decide to do the 2 RH axle shafts and narrow the explorer axle. They're about $200 out of yards around me. You do have the added cost of driveshaft shortening and shock plates (I haven't looked closely to see if the 7.25" shock plates can be slotted to fit the ranger's 2.75" U-bolts), and the cost or time/hassle of cut/weld perches, get parking brake cables to hook up, etc.

1" spacers turn my 57.125" rear axle into 59.125" mount face to mount face. that is 5/8" wider than a ranger axle or 1/2" narrower than an explorer axle, and 3/8" narrower than the suggested '66-67 B body rear end swap for dusters/dart sports/demons. It gets the front and rear track closer to each other. Measuring my duster, this width allows 235's out back with stock offset (+1/4") wheels before you have to start thinking about rolling the 1" wide fender lip at all, and 275's (maybe even 295's) with +30mm offset (up to 2004 mustang) wheels.

In this thread, I don't really want to get into the discussion of to use adapers or not, or alternatives to get BBP in the back. It was intended to gage interest, and if there is enough interest out there for what I'd call a "higher feature" adapter to actually make them.
 
My only thought would be screw in studs for the 1/2-20. Easy to find in different lengths.Depends on if the shop would want to instead of knurls.
I have a 72 Dart base Slant that is in the body shop for at least a year. Plan to do the disc swap up front.
Was going to start to look for the big bolt 7 1/4 or 8 1/4. But for $100 I'd run adapters on rear as the car will stay stock.
Plus it would help with the wider stance from the front disc swap. Even things out . My 2 cents.
screw in studs would add some cost. There might be some additional machining cost, as you are now tapping 5 holes instead of drilling/reaming. OEM grade press in studs are $.80-$1.50 each (the 2 press in studs I was looking at was $9-11 from rockauto for a pair of adapters), and just a quick search, looks like the least expensive screw in studs are from Dutchman or Currie and are $2/ea ($20 for 10).
 
As a guy who is using adapters to Just Roll Car Around I'm not at all concerned about hub centric.. I will convert to BBP once car is close to being ready.
 
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