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#1532128 - 11/11/13 12:34 PM Magnum 500 + 69 C-body drum brakes
69topless Offline
member

Registered: 11/23/08
Posts: 49
Loc: Czech Republic
Hi,

Im dealing for a while with the brake shake, which turns out being problem with fitment of the Wheels vintage Magnum 500 and original drums. It does not seat properly due the ribs/fins on the outer diameter and are sticked out, while seating area is deeper. So only studs holds the wheel in place although it was not seating properly. I have not notice it due the centre caps mounted on the wheel.

Original wheels fits nicely and the braking shake problem is gone. It sits on the hub with diameter around 2,75inch, but Magnum 500s is just 2.125 in.

I believe, I have only these options:
1st. purchase different shape of the drum, like ie. RAYBESTOS Part # 1924R with sticked out seating area (would have to verify the drum size for correct fitment and estimate the hub diameter distance from the drum. Still deal with smaller diameter on Magnum 500 then original size wheel :-/ ) Can anyone confirm, the wheels sits on the hub correcly with the new drum?



2nd. make a front disc brake conversion. I believe a correctly selected disc would have a needed Center Bore Diameter 2.125in. Im aware of all the benefits like a way better braking but not in the mood for +1000usd investment for conversion set right now.

3rd. change a wheels/tires to original wheels, get as wide white wall tires as possible (235?) and sell Magnum 500s

4th. use a small width spacer to seat the whell properly and forgot about hub for centric the wheel. But I think the lugs for centric of the wheel is just not enought. But on the other hand, this is how the rear wheels are mounted. It might also require to change to longer studs.

Whats your suggestion? Do you have any better ideas?

Original drum with hub


Magnum 500s inside view, notice the teeth from drums ribs


Current fitment. Not noticed before because of the centre caps


Wheels comparison



EDITED pictures, they were too big to display.


Edited by 69topless (11/11/13 11:42 PM)

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#1532129 - 11/11/13 01:54 PM Re: Magnum 500 + 69 C-body drum brakes [Re: 69topless]
RapidRobert Offline
Circle Track

Registered: 11/20/03
Posts: 33805
Loc: Lincoln Nebraska
I couldn't get the attachments to open
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#1532130 - 11/11/13 02:16 PM Re: Magnum 500 + 69 C-body drum brakes *DELETED* [Re: RapidRobert]
69topless Offline
member

Registered: 11/23/08
Posts: 49
Loc: Czech Republic
Post deleted by 69topless

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#1532131 - 11/11/13 02:20 PM Re: Magnum 500 + 69 C-body drum brakes [Re: 69topless]
RapidRobert Offline
Circle Track

Registered: 11/20/03
Posts: 33805
Loc: Lincoln Nebraska
still cant but if you're good on your end then it must be an issue with my computer. Maybe someone else will chime in
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#1532132 - 11/11/13 02:23 PM Re: Magnum 500 + 69 C-body drum brakes [Re: RapidRobert]
6bblgt Offline
I Live Here

Registered: 01/20/03
Posts: 15387
Loc: Las Vegas, NV
drum pic only shows up


Attachments
7920450-raybestos_1924_R.jpg (43 downloads)

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#1532133 - 11/11/13 04:26 PM Re: Magnum 500 + 69 C-body drum brakes [Re: 69topless]
denfireguy Offline
top fuel

Registered: 06/15/08
Posts: 1808
Loc: Colorado
Might try posting them one at a time. I got the pictures to pull up by going direct to your hosing service. I would repost them here but they are 2 megs each so they will not fit on here.

Here are the direct links:

Original drum with

http://s21.postimg.org/sgh55j0li/drum.jpg

Magnum 500s inside view, notice the teeth from drums ribs

http://s12.postimg.org/mixf4b8gc/press.jpg

Current fitment

http://s21.postimg.org/5kijy1tc6/magnum.jpg

Wheels comparison

http://s11.postimg.org/alk7957j6/compare.jpg

Craig


Edited by denfireguy (11/11/13 04:32 PM)
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#1532134 - 11/11/13 05:09 PM Re: Magnum 500 + 69 C-body drum brakes [Re: 69topless]
DAYCLONA Offline
I Live Here

Registered: 12/10/07
Posts: 15791
Loc: Mass
The Magnum/Roadwheel relies on the lugs to center the wheel, and I understand the finned C body drum aggravates that issue....either change out the drums, or add a 1/4 spacer and use the correct lugs to center the rim, just make sure you have at least 3/4's of the studs length in the lugnut for proper capture


Attachments
7920631-spacer.JPG (38 downloads)


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#1532135 - 11/11/13 05:10 PM Re: Magnum 500 + 69 C-body drum brakes [Re: DAYCLONA]
DAYCLONA Offline
I Live Here

Registered: 12/10/07
Posts: 15791
Loc: Mass
.


Attachments
7920633-spacer2.JPG (44 downloads)


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#1532136 - 11/11/13 11:49 PM Re: Magnum 500 + 69 C-body drum brakes [Re: DAYCLONA]
69topless Offline
member

Registered: 11/23/08
Posts: 49
Loc: Czech Republic
Thanks for hints to everyone. I have these lug nuts, as you post in the picture. I might prefer to change drum then add spacer and longer studs. My theory is, that Magnum 500s will seat properly on the new drum and even the hub will fit centre bore diameter of 2.125 inch at correct distance from the drum.

Anyone can confirm correct fitment, having the drum Raybestos Part # 1924R with the Magnum 500s?

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#1532137 - 11/12/13 08:22 AM Re: Magnum 500 + 69 C-body drum brakes [Re: 69topless]
Supercuda Offline
I Live Here

Registered: 09/04/07
Posts: 13405
That is some serious balancing weights on the new wheel, something not right there.

I have never seen fins wrap around the face like that before, not saying it isn't so as it obviously is, but I have never seen it. Only fix I can think of is different drums or a spacer.

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#1532138 - 11/12/13 09:54 AM Re: Magnum 500 + 69 C-body drum brakes [Re: 69topless]
demon Offline
super stock

Registered: 02/06/06
Posts: 979
Loc: Canada
Those finned brake drums can be replaced with regular 65-68 style drums. They swap directly. Been there done that


Edited by demon (11/12/13 10:07 AM)

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#1532139 - 11/12/13 01:34 PM Re: Magnum 500 + 69 C-body drum brakes [Re: demon]
69topless Offline
member

Registered: 11/23/08
Posts: 49
Loc: Czech Republic
Perfect news,I will double check the fitment and replace the drums

EDIT: I have just found out the current drums are HD 3 inch. Replacing to only front drum found online mentioned above with dimensions 11" X 2-3/4 would require also to change to smaller brake pads.

Or I might just grind off the offending small portion of the inner ribs on the existing drum. What is your opinion about this possibility?



Edited by 69topless (11/12/13 01:58 PM)

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#1532140 - 11/12/13 01:40 PM Re: Magnum 500 + 69 C-body drum brakes [Re: Supercuda]
69topless Offline
member

Registered: 11/23/08
Posts: 49
Loc: Czech Republic
Quote:

That is some serious balancing weights on the new wheel, something not right there.

I have never seen fins wrap around the face like that before, not saying it isn't so as it obviously is, but I have never seen it. Only fix I can think of is different drums or a spacer.




The wheels are OK, were checked for damage by pros recently. Way to much of the weights is due the improper machine used for balancing with intension not to place the weights on the outside of the wheel. Will take it to other place for new balancing next spring.


Edited by 69topless (11/12/13 01:58 PM)

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#1532141 - 11/12/13 03:33 PM Re: Magnum 500 + 69 C-body drum brakes [Re: 69topless]
Supercuda Offline
I Live Here

Registered: 09/04/07
Posts: 13405
I wondered if it was a balancing issue (machine and/or operator) rather than the wheels as there appears to be a lot of weight directly opposite even more weight.

As for changing the width of the shoes, I would NOT do that. The fronts are 3 inches and the rears less for a reason. Your braking balance will be messed up if you make the front shoes 2.5 inches. Your front brakes provide more of the total braking force than the rears and on an all drum system most of that is built into the shoe width.

Before you spend any money consider a disc brake upgrade for the fronts.

Since I do not know what C baody you have I looked up the front drum for a 69 Chrysler 300 on rockauto.com.

Raybestos makes a 3 inch front drum that fits and does not have those fins. So the proper ones are out there.


Edited by Supercuda (11/12/13 03:37 PM)

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#1532142 - 11/12/13 10:45 PM Re: Magnum 500 + 69 C-body drum brakes [Re: 69topless]
demon Offline
super stock

Registered: 02/06/06
Posts: 979
Loc: Canada
Quote:

Perfect news,I will double check the fitment and replace the drums

EDIT: I have just found out the current drums are HD 3 inch. Replacing to only front drum found online mentioned above with dimensions 11" X 2-3/4 would require also to change to smaller brake pads.

Or I might just grind off the offending small portion of the inner ribs on the existing drum. What is your opinion about this possibility?





replace your finned 11x3 drums with 65-68 11x3 drums. It's that easy.
Yoh can't change shoe sizes without changing the backing plates and hardware too. Don't create a pile of work and expense. Find an old New Yorker or whatever, grab the drums and stick them on your car.

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#1532143 - 11/13/13 12:41 PM Re: Magnum 500 + 69 C-body drum brakes [Re: demon]
69topless Offline
member

Registered: 11/23/08
Posts: 49
Loc: Czech Republic
My car is 69 Dodge Polara convertible 383cui. I have checked the rockauto and they list 11x3 drums under 440cui engine trim. Its RAYBESTOS Part # 1938R, Front; 11" X 3" Brakes.

Will keep the fix as easy as possible, going with the no finned 11x3 drums. Driving mostly with the top down while cruisin, Im easy on brakes. Will report the wheel fitment in few months, once have the parts imported to central Europe and snow is gone thanks everyone for help


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#1532144 - 11/13/13 01:58 PM Re: Magnum 500 + 69 C-body drum brakes [Re: 69topless]
dogdays Offline
I Live Here

Registered: 01/20/03
Posts: 16168
Something needs to be repeated here, your wheels ARE NOT HUBCENTRIC! Period.

The 2.125" hole is for mounting the cap that finishes the look, it has NOTHING to do with anything else.

You are correct, the fins are holding the wheel away from the face and causing your problems.

You could grind off the fins in the area where they hit the wheel. Either use a handheld right angle grinder and spin the drum as you grind off the fins, or else put the drums in a lathe and machine off the fins so the wheel fits flat against the drum. Or, change to non-finned drums. Or, use a spacer.

These wheels are really cool, but one has to understand they are for appearance, not really for high performance.

R.

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