Hub drilling

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shep76

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If my hubs/drums look like this, does that mean someone drilled them to be the bigger bolt pattern? Is there anything inherently dangerous/wrong with redrilling like this? Will I need to redrill the drums whenever I get new ones or can I find them predrilled?

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I don't recall what's in the back side between the OEM stud locations

If it is thinner then a major amount of strength is missing.

Also if the stud holes were not centered you could have vibrations
 
Hmmm. Yeah, it just looks kind of hokie to me. Ok, I'll start searching on here for options. May be better off just doing a disc brake conversion to clean all this up. Thank you.
 
Yes, someone drilled them out and mounted new studs to get the big bolt pattern. Not a terrible thing, and it looks like a competent job. The concern is the narrow amount of "meat" on the outside of the new studs.

You could always just knock those out and go back to small bolt pattern... with extra "lightening holes"...
 
4" to 4.5" bolt pattern, the lugs obviously fit your wheels so buy the correponding drums. As far as strength is concerned, you may have an issue. Get photos of the back side and post them here.

Thanks for sharing.
 
mvh said:
Yes, someone drilled them out and mounted new studs to get the big bolt pattern. Not a terrible thing, and it looks like a competent job. The concern is the narrow amount of "meat" on the outside of the new studs.

You could always just knock those out and go back to small bolt pattern... with extra "lightening holes"...
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Ha! lightening holes... funny. Right, that is true. The rear is the bigger bolt pattern but I'm not sure I care that much. I like the idea of keeping it stock if it all works ok. Just easier to work on and maintain.
 
mvh said:
Yes, someone drilled them out and mounted new studs to get the big bolt pattern. Not a terrible thing, and it looks like a competent job. The concern is the narrow amount of "meat" on the outside of the new studs.

You could always just knock those out and go back to small bolt pattern... with extra "lightening holes"...
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I Agree.. And if you need new drums I'd look at swapping on B body BBP drums... As long as the offset matches it should be fine.... I don't see the amount of meat outside the studs as being concerning at all....

Question is when the bolt pattern was redrilled did the person doing the work spot face the back side of the hubs where the studs are?
 
69FBCuda said:
4" to 4.5" bolt pattern, the lugs obviously fit your wheels so buy the correponding drums. As far as strength is concerned, you may have an issue. Get photos of the back side and post them here.
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The wheels are throw aways so I'm not married to them. I just want it to all be safe really.
1WildRT said:
I Agree.. And if you need new drums I'd look at swapping on B body BBP drums... As long as the offset matches it should be fine.... I don't see the amount of meat outside the studs as being concerning at all....
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I didn't think of that. The width on the drums is all the same? I can just order 1973 dart drums? Thank you
 
shep76 said:
The wheels are throw aways so I'm not married to them. I just want it to all be safe really.

I didn't think of that. The width on the drums is all the same? I can just order 1973 dart drums? Thank you
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A body drum brakes stayed SBP... Look at 10"drums for a 318 Coronet....

Make sure they are the same width..
 
shep76 said:
The wheels are throw aways so I'm not married to them. I just want it to all be safe really.

I didn't think of that. The width on the drums is all the same? I can just order 1973 dart drums? Thank you
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Problem is the center register on that small bolt pattern hub is smaller than the larger bolt pattern (LBP). So a LBP drum won't center properly.

If you replace these, you'll have to drill out a set of SBP drums. And same with rear drums too.

Probably don't drive this everyday so not a huge rush.

Might find a conversion at Spring Fling show/swap in April. I know McKellar's from Bakersfield will be there with new disk and axle setups (for 8 3/4). Used disk conversions are usually there for sale and might find a used large bolt 7 1/4 if that's an option.
 
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There are machines that do this and they are accurate.

One of my friends has one.

The first thing I'd do is make sure you can get a drum that fits the shoes and backing plate.

I have to correct the statement about A body drums.
They did NOT stay SBP.
73 and up disk brake cars had LBP rear drums.

If drums are available, I'd consider plugging the SBP holes and welding them in.
 
How long have these been on the vehicle............and working?
Are the current drums shot?
Are you satisfied with drum performance?




FWIW, I like the LBC myself.
I changed my stock 9" drum setup for '74 Dart LBC manual discs, UCAs, and MC.

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I've also had redrilled LBC rear axles with 1/2" screw in studs for a long time.

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1706885472940.png
 
Daves69 said:
How long have these been on the vehicle............and working?
Are the current drums shot?
Are you satisfied with drum performance?




FWIW, I like the LBC myself.
I changed my stock 9" drum setup for '74 Dart LBC manual discs, UCAs, and MC.

View attachment 1716200962

I've also had redrilled LBC rear axles with 1/2" screw in studs for a long time.

View attachment 1716200969

View attachment 1716200963
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I just got the car a few weeks ago. It hasn't been registered since 2004 so I'm not sure how long it was driven after drilling. Really this is the first thing I did. Removed the front wheels to start rebuilding suspension and brakes. The rear is 8.25" but I have not removed the wheels yet so not sure what I will find, the bolt pattern is 4.5" on the rear. Seems like there are lots of options so I think I just need to do some research. I don't mind spending money and making big changes I just don't want to redo things because of making poor choices. It is a 360 car now, I'm not planning on doing any racing or anything like that so maybe the current setup is more than adequate.... It definitely needs new ball joints and bushings. Thank you
 
autoxcuda said:
Problem is the center register on that small bolt pattern hub is smaller than the larger bolt pattern (LBP). So a LBP drum won't center properly.

If you replace these, you'll have to drill out a set of SBP drums. And same with rear drums too.

Probably don't drive this everyday so not a huge rush.

Might find a conversion at Spring Fling show/swap in April. I know McKellar's from Bakersfield will be there with new disk and axle setups (for 8 3/4). Used disk conversions are usually there for sale and might find a used large bolt 7 1/4 if that's an option.
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Probably shouldn't be changing the subject here but I see disc brake conversion kits all over ebay.... Are the used sets from swap meets just less expensive or have people had issues with the ebay kits. I did a quick search but didn't see any mention.
 
My opinion would be to get factory/OEM stuff from a 73 and up disk brake car.

...and also the rear wheel cylinders for the same car.

I just looked at your OP pics.

IMO there's plenty of meat on that hub as is.
 
I run that same setup on my duster,10 inch hub and drums,drilled to 4.5 bolt pattern with screw in studs. I had it done in the '80s and have no issues.
 
shep76 said:
Probably shouldn't be changing the subject here but I see disc brake conversion kits all over ebay.... Are the used sets from swap meets just less expensive or have people had issues with the ebay kits. I did a quick search but didn't see any mention.
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most of the disc conversion kits are based off of the 73~76 factory set up. almost none of them include the upper control arm, so you're on your own to source those or use your small ball joint early arms with an adapter for the balljoint taper.

almost none of them supply the right lower balljoint bolts, so if you're running a swaybar expect to make adjustments there.

beyond that, it's a drop in swap and all the brake stuff is widely available-- caliper, discs, etx.

the repopped upper control arms come in and out of availability and run about 240+

you can save some dough buying used and then you get to select all the balljoints and bushings you want instead of just whatever comes with the kit. if you're going to buy new, get it from doctor diff. cass is a good dude and sells good parts. 10.95" Front Disc Brake Kit (Stage 1)

now would be the time to thing about whether or not you want to upgrade the entire front to 73~76 if you're going that way. k-member, lower control arms, steering. so that it's all the same system.
 
shep76 said:
I just got the car a few weeks ago. It hasn't been registered since 2004 so I'm not sure how long it was driven after drilling. Really this is the first thing I did. Removed the front wheels to start rebuilding suspension and brakes. The rear is 8.25" but I have not removed the wheels yet so not sure what I will find, the bolt pattern is 4.5" on the rear. Seems like there are lots of options so I think I just need to do some research. I don't mind spending money and making big changes I just don't want to redo things because of making poor choices. It is a 360 car now, I'm not planning on doing any racing or anything like that so maybe the current setup is more than adequate.... It definitely needs new ball joints and bushings. Thank you
Click to expand...

If you have an 8.25” rear axle they were all 4.5” bolt pattern from the factory, so you should just find the stock axles and 10x2.5” BBP drums in the back.

shep76 said:
Probably shouldn't be changing the subject here but I see disc brake conversion kits all over ebay.... Are the used sets from swap meets just less expensive or have people had issues with the ebay kits. I did a quick search but didn't see any mention.
Click to expand...

Don’t mess with any of the eBay kits unless they’re from DoctorDiff, as he sells on eBay too.

He’s not the cheapest, but he will get you all the right parts, and the highest quality reproduction parts that are currently available. Plus his customer service is awesome, so if you do have any issues or questions you can just email him. Cass is the best!

And yeah, if you need bushings and ball joints and all of that anyway, now would be the time to go disk up front because all that stuff has to change anyway. You’ll probably spend almost the same amount to rebuild everything you’ve got as it will cost to convert to disks.

As far as the swap meet stuff, you can probably save a little on some stuff, like spindles and control arms. But you’ll almost certainly still need to replace all the bushings and ball joints, and will likely need new bearings, rotors, and probably rebuild the calipers anyway. So, you could easily end up spending just as much or more, depending on how much you buy and how much of it needs to be rebuilt anyway.

Even when the FMJ cars were in the yards and i could get wrecking yard prices I only took spindles and caliper brackets unless the calipers were super clean, because after core charges and everything it was cheaper to just buy rebuilt and new everything else.
 
FWIW You live in Camarillo Ca... I've been through there enough to know about the traffic... You might drive like grandma... But the idiots around you don't.... I'd want a car that stops quickly & consistently every time.... Put the 73-76 discs on it...... JMHO
 
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