Brake drum question

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71DodgeDemon340

71DodgeDemon340

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Im having billet aluminum adapters made for my demon so i can get rid of the cast ones, i was looking at the drums and i believe they are 10x2 1/4 drums, my questions are is can i remove the tiny flange on the frontside of the drum without it affecting anything?

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Just grind it down flush so my adapters will go flush up against it
 
Naw, those are junk, send em to me . I'll trade you some other ones I got kicking around. Those huge flanges just get in the way of everything....Hah. Kidding!

Do not modify those drums. They are getting harder to find all the time. Those "huge" flanges serve two purposes. #1) they dissipate heat faster,than regular drums, and 2) they help keep the drum from bell-mouthing. Those things,on the back of your A-body, for street and mild performance driving,are probably the best thing you could have back there.
But if you really want to get rid of them, put me first in line.

Oh, in answer to the cutting off, of that centering ring; DONT do it.
Better it would be to machine the adapters. But best would be to get proper-fitting wheels.
That centering ring performs a special function. It may never get used on your car. But in hard running/braking that drum may get very,very,hot.Thats its function; to convert forward motion into heat. When it gets hot, it expands. A lot. When it cools it contracts back to its former size. That centering ring makes sure that when it does its growing and shrinking, that it stays centered on the axle. As long as its centered, it stops smoothly. If the drum were to shrink back off-center then on the next brake application, there would be a terrible vibration created inside that drum, as the off-center drum forced the shoes into an ever-changing eliptical path. If you shave it, you would be compromising its ability to do its job.It fits into the cavity of a stock wheel, because of the way that wheel is formed. If you look at period aluminum wheels, you will see that they were machined for that"ridge".If you look at the back of your cast adapters, they should be too, or at least have plenty of clearance.
BTW; They used to make adapters, SEMA approved. Depending on the class, we used to be able to run those in dragracing.
 
Lol if they are junk how come you want em

You think id be ok grinding that little lip flush?
 
I would machine adapters to fit the drum. A simple relief should do that
 
I know, i hope the machinist did that if so than thatll work out perfect, but he shipped them today before i even thought about it, its a tiny lip, is that from stamping or what?
 
That ridge has a very important job.It aligns the brake drum to the axle to have the drum as close to zero run out.Something that is called "Hub Centric". If removed the drum may have excessive run out that you will know it when you step on the brake.That is the best way I can explain it. Just a thought.
 
But its only .080" high surely i can grind that down flush and the pilot hole still be correct, i think its a left over result of stamping or forging, the drum is about 1/8" thick
 
Yeah i realize that lol just making sure before i do something that ruins my drums, ill just take some off of the adapters if the machinist didnt
 
You asked for advice no take it, someone here is just bull headed. Don't grind it, get a machinest like you were told.
 
They came off my car. They're called mine,and I want 'em back. lol

They were part of the Trailer Towing pkg,found on 67up A-bodies;Option Code 359(67/68).They might have been part of other pkgs, as I have found them on 340 equiped; Swingers,Dusters, and Demons, without hitches.
I thought they were part of the Rallaye Group, the Formula S group, and the Cuda Group, but find no references to support that.
They were available separately as code B11.
 
AJ/FormS said:
They came off my car. They're called mine,and I want 'em back. lol

They were part of the Trailer Towing pkg,found on 67up A-bodies .
Click to expand...

Interesting....they came with an 8 3/4 I bought...maybe thats why it had those drums on it. I was just going to trash them but sounds like they are better than getting a new set....guess I'll clean them up instead.
 
charger426, Can't say if the name is correct but always been called "Bell" drums.A bodies with 1 3/4''x10'' rear drums.Just a guess about mid 60's to mid 70's.I do know that they also came in 9''. Found a few at Pic-a-Part from a Dart and thought "Score" but found they were 9'' when I got them home.
The 10'' go for a good price used. I paid $75 for one.
 
AJ/FormS said:
Naw, those are junk, send em to me . I'll trade you some other ones I got kicking around. Those huge flanges just get in the way of everything....Hah. Kidding!

Do not modify those drums. They are getting harder to find all the time. Those "huge" flanges serve two purposes. #1) they dissipate heat faster,than regular drums, and 2) they help keep the drum from bell-mouthing. Those things,on the back of your A-body, for street and mild performance driving,are probably the best thing you could have back there.
But if you really want to get rid of them, put me first in line.

Oh, in answer to the cutting off, of that centering ring; DONT do it.
Better it would be to machine the adapters. But best would be to get proper-fitting wheels.
That centering ring performs a special function. It may never get used on your car. But in hard running/braking that drum may get very,very,hot.Thats its function; to convert forward motion into heat. When it gets hot, it expands. A lot. When it cools it contracts back to its former size. That centering ring makes sure that when it does its growing and shrinking, that it stays centered on the axle. As long as its centered, it stops smoothly. If the drum were to shrink back off-center then on the next brake application, there would be a terrible vibration created inside that drum, as the off-center drum forced the shoes into an ever-changing eliptical path. If you shave it, you would be compromising its ability to do its job.It fits into the cavity of a stock wheel, because of the way that wheel is formed. If you look at period aluminum wheels, you will see that they were machined for that"ridge".If you look at the back of your cast adapters, they should be too, or at least have plenty of clearance.
BTW; They used to make adapters, SEMA approved. Depending on the class, we used to be able to run those in dragracing.
Click to expand...

ooops . i just put 2 new drums on the back of my car and took those old drums that you said are rare to the dump... they are no good once they pass their nominal thickness... why would you want those old ones??
 
tarvin
No good by who's definition?
No I dont want your "no-good" ones. That post was written in a comedic spirit.My wife never fails to remind me about my lousy sense of humor. I guess it does not come across very well on the internet either.

When those drums are new, as in not-worn, they have the ability to shed heat pretty good.Since my car is set up with 295s out back, I was able to send a very large amount of stopping power out there. Those flanged drums are a bonus for me, cause they make it possible for me to get away with that. Also,the rear brake parts are much cheaper to replace than the KH rotors.I put soft shoes back there, and they dont last very long, but they're quiet, and easy on the drums.
 
AJ/FormS said:
tarvin
No good by who's definition?
No I dont want your "no-good" ones. That post was written in a comedic spirit.My wife never fails to remind me about my lousy sense of humor. I guess it does not come across very well on the internet either.

When those drums are new, as in not-worn, they have the ability to shed heat pretty good.Since my car is set up with 295s out back, I was able to send a very large amount of stopping power out there. Those flanged drums are a bonus for me, cause they make it possible for me to get away with that. Also,the rear brake parts are much cheaper to replace than the KH rotors.I put soft shoes back there, and they dont last very long, but they're quiet, and easy on the drums.
Click to expand...

I totally agree that the big fine is wonderful to have, I had them and lucked out and found 2 of the centric (sp) and put them on... i hated to throw them out but they were were out of spec... didnt know if some people still used the out of spec ones or not... it was sounding like you wanted that style useable or not, i was starting to feel like i shouldnt have thrown them out... you never know who may want them for looks or something i guess... LOVE my new ones though....what a difference they made. I have the 295/50/15 also, going to get the 305's when these are wore out, thats as big as i can fit.
 
Up here I cant find 305-15s anymore. The last time they were in a catalog was about 2004. I had a search done the next year, at the tire shop were I was working at the time. Reply came back, disco'd,-none in Canada.
I have a set of 325/50-15s I occasionally run.They're drag radials tho, and street duty chews em up pretty quick. I put em on for show. I have to slow down for the corners a bit. I hate slowing down for corners!
 
AJ/FormS said:
Up here I cant find 305-15s anymore. The last time they were in a catalog was about 2004. I had a search done the next year, at the tire shop were I was working at the time. Reply came back, disco'd,-none in Canada.
I have a set of 325/50-15s I occasionally run.They're drag radials tho, and street duty chews em up pretty quick. I put em on for show. I have to slow down for the corners a bit. I hate slowing down for corners!
Click to expand...

m50-15 pro tracs... or mickeys...
 
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