TheSamba.com :: View topic - Re-Drilling Brake Drums

Sun Aug 10, 2008 10:56 am

Anyone ever re-drill brake drums to fit other wheels lug patterns? I'm going to try it soon on some extra drums I have in order to fit full sized ( 1979) bronco wheels on my buggy. If anyone has done this, and has any words of caution or experience I'm all ears .

Sun Aug 10, 2008 11:52 am

If you look at the inside of a VW drum, you'll see the holes for lug nuts are drilled in the section of the drum with thick cast raised webs. Redrilling them with a new pattern with holes in the thinner metal between the webs will make them weaker. VW obviously thought the webs were essential, however, lots of people have re-drilled them. Its your choice.

Maybe if there's enough room to clear the shoes, etc., you can add a steel doubler plate inside the drum held by the studs.

Sun Aug 10, 2008 12:36 pm

There are a few company's that have undrilled drums & you can order them dilled for your application. If it were me I would order new disc brakes with the pattern you want. Being larger rims & tires you will find you need more braking power. It will save you headaches now & later on.

Sun Aug 10, 2008 12:38 pm

New drums drilled in Ford or Chevy patterns ore only $50 each and don't have the reinforcing boss problems of the stock drums. Money well spent.

Sun Aug 10, 2008 1:03 pm

IIRC, full size Bronco wheels have a 5x5.5" bolt pattern...so off-the-shelf VW drums drilled for a standard Ford pattern wouldn't work.

Get blanks and have them drilled.

Sun Aug 10, 2008 1:49 pm

manxcraig wrote: New drums drilled in Ford or Chevy patterns ore only $50 each and don't have the reinforcing boss problems of the stock drums. Money well spent.
where did you find them?
I've searched with no luck

Sun Aug 10, 2008 2:45 pm

FarmerJohn wrote: manxcraig wrote: New drums drilled in Ford or Chevy patterns ore only $50 each and don't have the reinforcing boss problems of the stock drums. Money well spent.
where did you find them?
I've searched with no luck

So-Cal Imports. I got mine about 3 months ago and got rid of my adapters.

Good catch on the Bronco pattern, I didn't know.

Sun Aug 10, 2008 7:50 pm

Thanks guys, I will certainly look into getting new drums drilled to the 5x5.5 pattern. I am heavily considering this pattern due to the fact that I have the General Lee style wheels which are in VERY nice shape, 10" wide. I also have a complete set of 30 year old aluminum slot wheels in pretty good shape in that pattern too. Not to mention two or three sets of very wide older ( needing repaint ) wagon wheels.

Sun Aug 10, 2008 8:25 pm

I got mine from so-cal also. Disks in the front and drums in the rear, drilled and studded for 5 on 4.75, about 200 bucks. Top notch pieces!!

It cost about the same for (not the cheap ones) nice billet adapters, then you have the offset problem. Do it right the first time and it will be cheaper in the end.

Mon Aug 11, 2008 4:53 am

Continuing with this.........would the totally blank, brand new drum also have the raised ares as well? That would kind of put me right back to where I am now. If I go and re-drill what I have now, I also do plan to fill in the reamaining leftover holes to try and re-gain at least some of the structural integrity of the drum face.
It would be a real bonus if the new blanks had the raised areas right around the entire span on the back side of the drum. Then I would have 100% confidence in the whole conversion.

Mon Aug 11, 2008 5:12 am

I drilled mine (Front) using the adaptor as a guide, did not worry about the ridges. Just pressed in the adaptor bolts from the back and have had them on for 5 years now and no issues. Even at 80+ mph.

I did check for cracks and stress issues for the 1st year regularly but now only re-check them once a year.

Doubt you need to worry about filling in the original holes, the less heat you through at these, the better imho.

Good luck.

BTW, going to a disk setup this fall...

Tue Aug 12, 2008 9:10 am

63scout wrote: Continuing with this.........would the totally blank, brand new drum also have the raised ares as well? That would kind of put me right back to where I am now. If I go and re-drill what I have now, I also do plan to fill in the reamaining leftover holes to try and re-gain at least some of the structural integrity of the drum face.
It would be a real bonus if the new blanks had the raised areas right around the entire span on the back side of the drum. Then I would have 100% confidence in the whole conversion.

Blank drums are of even (ie thick...) thickness all around.

Tue Aug 12, 2008 2:30 pm

That the news I was hoping to hear !