anyone ever tried this? drilling drums?

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There are a few things to look at when doing this.
1. Balance, your removing material which can affect the balance. You can't just get a drill bit and go to it, you have to properly map it out. If you do and you still have balance issues you can remove some material off the fins to balance it out.
2. Strength, Are your rotors thick enough to handle this? If you drill the holes to small they will pretty much be useless. If you go too big you risk structural failure. Two things can go wrong here. One you may just crack the rotor Leaving you at ground zero. The other is you risk twisting the rotor again leaving you back at square one.
I'm not saying not to do it, the benefits can out weigh the draw backs, especially if your on a tight budget. Just plan it out first, protect the bearings at all cost, and make sure there are no burs on the inside of the drum to damage the pads.
 
Heres my thoughts....if it would have done any good and been structurally sound shelby would have done it already. I mean the man redesigned the complete suspention geometry by drilling a few holes and adjusting the alignment and ford couldnt figure that out.

It was a Ford engineer that developed the Shelby drop, not Carroll. His name was Klaus Arning and he passed it on to Shelby. Ford did not think it was cost effective.
Just about everything Shelby got credit for on the mustang's was designed by Pete Brock including the Daytona coupe.
 
It was a Ford engineer that developed the Shelby drop, not Carroll. His name was Klaus Arning and he passed it on to Shelby. Ford did not think it was cost effective.
Just about everything Shelby got credit for on the mustang's was designed by Pete Brock including the Daytona coupe.

The really dumb thing is, why didn't Shelby (Arning) have enough sense to use a wedge between the upper balljoint and the control arm, on the R-models, to keep the ball joints from binding?

Street Shelbys got a 1-inch drop which had no binding issues, but R-models got 1¼" drop, which did cause binding issues. -A simple wedge would have eliminated this problem.
 
That's funny. First, with a one inch drop, the ball joints don't bind, so why slap a wedge in there? I've never heard about the R-models getting a larger drop, I always read they had the same drop as the street Shelby Mustangs, due to SCCA rules. Maybe because "monkey-see-monkey-do" engineering doesn't exist when you're the first monkey to the banana tree.
Shelby was a little reluctant to change stuff just to be changing. Time and time again I've read that he was slow to change the leaf-spring chassis on the 289 Cobras because in his words, "they're winnin' ain't they?" Since the R-model Mustangs were dominating, I doubt they felt the need to fine-tune anything.
Also drilling drums was pretty common among the Corvette teams when Corvette's had drum brakes, I'd play it safe and drill the backing plates myself.
 
stand corrected.

I was thinking that too about drilling the backing plates. There is room. could you not add some sort of funnel for catching air and nipple with hose for channeling it into the drum? I am sure that smarter people than I have probably already thought of this.
 
I'm thinking of doing something similar with the brake scoops on my clone. I think it would work if you used a flexible duct hose attaching from the wheelwell where the brake ducting for the scoops attaches and then attach the other end to some sort of a funnel thingie to the backing plate. Is it necessary for the street? Nope. Would it look cool? I think so.
 
It's not recommended to even drill rotors. They have the potential to heat crack around the holes due to rapid cooling.

Forget about drilling drums. They're still drums no matter how you drill 'em.
 
The really dumb thing is, why didn't Shelby (Arning) have enough sense to use a wedge between the upper balljoint and the control arm, on the R-models, to keep the ball joints from binding?

Street Shelbys got a 1-inch drop which had no binding issues, but R-models got 1¼" drop, which did cause binding issues. -A simple wedge would have eliminated this problem.

I've had mine bind a couple of times with a 1" drop. Pretty freaky. You're in a turn, and all the sudden, it doesn't want to stop turning. I really had to fight it to bring it back straight. I'm lucky a car wasn't in the next lane because I assumed it.
 
it was very, very common to drill the drums on old Nascar racers in the 50's and 60's before the advent of disc brakes and before Nascar rules allowed them. nothing inherently wrong with drilling the drums so long as they are done correctly and the holes are chamferred after drilling. that said, if you are thinking about drilling the front drums instead of converting to discs...don't do it, however, if you're talking about drilling the rear drums that's fine as long as they are regularly checked for cracks and such, at least every time you change your oil or rotate your tires, no more than 5000 miles