changing rear axle from sbp to lbp

-
Status
Not open for further replies.
C

cooltx

Well-Known Member
Joined
May 6, 2008
Messages
55
Reaction score
1
Rating - 0%
0   0   0
Contact seller
I have a '71 Duster that I'm changing the axles from the small bolt pattern to the large bolt pattern. I'm looking for the backing plates and hubs that will fit this in the DFW Texas area. Thanks. oh, it is an 83/4
 
Backing Plates Should Be Same As Long As You Stay Same Size Drum, I Had Mine Drilled Out[drums] For Larger Bolt Pattern--just Take Your Drums To A Machine Shop Or Do Them Yourself On A Drill Press, Just Make Sure You Are Very Accurate In Marking Holes To Be Drilled, I Have Done This Twice And Not To Difficult.
 
I've always heard if you go with aftermarket axles that the offset is different than stack a-body axles therefore one of two things need to be changed .
1 the stock a-body drums need two be turned for clearance along the edge
that interfaces with the backing plate or 2 the backing plates and drums will need to be changed to those like on b/e bodys . Because most aftermarket manufacturers use the larger cars offset and don't change any of the machining when the produce the bbp a-body axles. As they've become aware of that they may have changed that practice. When I changed the axles in My Dart I aquired a B-body 8 1/4 axle with 10" X 2 1/2" brakes everything fit perfect! I dod have an extra set of backing plates if your interested I have the drums too but They're pretty scored up not sure if they could be turned .
Let Me know if your interested. Not in dfw area n.Cal. So you'd have to pay for shipping...
 
Yes- Thats Partly So , If You Use Stock Style Axles For A-body They Will Be A Direct Fit Only Need To Redrill Bolt Pattern In Drum, If You Use Aftermarket Axles Then You Would Have To Enlarge Center Hole In Drum Or Get Different Drums, As Far As Ofset I Know Of None, I Have Done This On A 69 And A 71 Dart With No Problems, With Aftermarket Axles[yukon[ I 1st Conferred With The Manufacturer As To What I Was Wanting, And What Yr,model ,make And Type Of Rear Axle I Was Using-------thus Being Said, If 'cooltx Is Using Stock A-body Axles When Changing Bolt Patterns, He Shouldnt Have A Problem With The Conversion, May Possibly Have To Enlarge Center Hole In Drum, If He Is Buying New Aftermarket Axles Then He Needs To Confer With The Manufacturer To Accomodate His Needs---i Was Referring To Stock Stuff.....................
 
I would, but have seen it done both ways no probs on street, if you are reffering to axles, if you are reffering to drums I wouldnt bother welding them back up..............
 
rbdart Yes- Thats Partly So , If You Use Stock Style Axles For A-body They Will Be A Direct Fit Only Need To Redrill Bolt Pattern In Drum, If You Use Aftermarket Axles Then You Would Have To Enlarge Center Hole In Drum Or Get Different Drums, As Far As Ofset I Know Of None, I Have Done This On A 69 And A 71 Dart With No Problems, With Aftermarket Axles[yukon[ I 1st Conferred With The Manufacturer As To What I Was Wanting, And What Yr,model ,make And Type Of Rear Axle I Was Using-------thus Being Said, If 'cooltx Is Using Stock A-body Axles When Changing Bolt Patterns, He Shouldnt Have A Problem With The Conversion, May Possibly Have To Enlarge Center Hole In Drum, If He Is Buying New Aftermarket Axles Then He Needs To Confer With The Manufacturer To Accomodate His Needs---i Was Referring To Stock Stuff.....................
Click to expand...

Thanks for clearing that up rbdart.
Perhaps I was misinformed . Don't wanna be going around spreading wrong info .I'm gonna measure all my old brake stuff and compare it with the stuff that's on there now. I'm running the yukon axles also btw
 
If the OP is going with a shelf aftermarket LBP axle, the standoff is different from the stock a body axles. Therefore, the stock SBP drums and backing plates will not work with a LBP moser,strange, yukon axle unless the axles is specifically buuilt for the A body standoff. Can't just open the SBP drum centering hole and get it to work.

If the stock A axles are redrilled to LBP, then the stock drum only need drilled for large bolt circle pattern.

The A body 8.75 axle standoff is ~2" and the others are ~2 5/16"
 
Get it from a 69-73 C body with 8 3/4. These are 11X2 1/2 or 2 3/4. Although they are heavier than the 10 inch stuff.
 
I bought a set of 11" drums and backing plates off of a 74 D100 van for $50 to do my conversion. I was told by Dr. Diff that I could use any brakes that came from a car with big bolt pattern.
 
The axle offset is the distance between the end of the green bearing and the inside of the plate on the end of the axle? Trying to think out a rear disc conversion and that is interesting about the difference of length. Gives more room for the caliper mounting bracket.
 
just have the small bolt pattern axles and drums redrilled for large bolt pattern. simple as that, nothing to buy. no muss no fuss no fit issues. but do take some of the money saved and replace everything under the drums!
 
thanks for the replys. I was planning on buying new moser axles w/ new bearings, but jimacuda's plan sounds cheaper , what do you guys think. I run slot mags , so far I've only spent cash on 2 15x8 slots with lbp. cooltx
 
I am building a stroker motor and running big tires, so I am not inclined to use 40 year old axles that have been drilled and filled. For a street car with limited traction, you would probably be ok.
 
yea, it's just a street car. but I do want to run a 275-60 tire. I'm cool with buying the new axles, I just gotta figure out the hubs abd backing plates.
 
I have 10 x 2 1/2" set up off a 68 Belvedere 8 3/4 with all new drums,shoes,wheel cylinders,self adjusting parts,etc and the E-brake cables. PM mee if interested. Also have the housing with the spring pads moved for in the rail mounting kit.
 
Status
Not open for further replies.
-

Back
Top