improved braking - anyone drill their brake drums?

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jaymaechtlen
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improved braking - anyone drill their brake drums?

Post by jaymaechtlen »

I read that a reasonable way to reduce fade in hard usage is to drill holes in the drum - article
http://www.chtopping.com/CustomRod4/
Comments?
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Re: improved braking - anyone drill their brake drums?

Post by toytron »

jaymaechtlen wrote:I read that a reasonable way to reduce fade in hard usage is to drill holes in the drum - article
http://www.chtopping.com/CustomRod4/
Comments?
Interesting.....When was that article written?

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Re: improved braking - anyone drill their brake drums?

Post by 66vairguy »

Drum drilling has been tried. Two issues. Drilled holes can eventually lead to fracturing (oddly enough cast holes don't seem to have this issue).

And secondly - it makes the drum brakes absolutely worthless in wet conditions.

Back in the day ----- backing plates were drilled to ventilate the brakes, often air scoops with flex tubes were installed - sometimes blower motors were added. Needless to day, not for daily driving.
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Re: improved braking - anyone drill their brake drums?

Post by jaymaechtlen »

The article claims " If you've driven a drum brake equipped car through water you know braking is non-existent. With holes in the drums, centrifugal force not only evacuates dust, but water immediately as well. But the main benefit is the fact that when drums are vented properly, so as to eliminate balance and material integrity problems, they virtually eliminate fade, which is.the primary reason discs replaced brakes while racing at the dry lakes."

the article's web page was last updated in 2001, I think.
Since I have disks on one end, I haven't bothered drilling the drums.
Has anyone tried it and found that it worsened behavior in the wet?
All of us have experienced the lack of brakes after going through a deep puddle with standard drums.

As far as cracking, I suppose that's a risk. You'd probably want to deburr the holes, maybe even chamfer them a wee bit.
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Re: improved braking - anyone drill their brake drums?

Post by bbodie52 »

Here are some additional comments and opinions...

Image
Drilled Brake Drums
:link: http://corvaircenter.com/phorum/read.php?1,597806



Drilling Drums
:link: http://www.tffn.net/drilldrum.html
Image

:dontknow: 👀😒


Brake fluid is hygroscopic, and since water accumulation in the brake fluid can lower the boiling point of the fluid and possibly cause brake fade during heavy braking, the brake fluid should also be flushed and replaced. Clark's recommends flushing and replacing the brake fluid every 2-3 years to reduce water contamination. The aging fluid in those brake lines probably has a high percentage of water in them. The water content can cause corrosion inside of the steel lines, decay in the flexible brake hoses, rust and corrosion damage in the wheel and master cylinders, etc.

Image
:link: http://www.corvair.com/user-cgi/catalog ... w_page=144

Image
Brad Bodie
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Re: improved braking - anyone drill their brake drums?

Post by 1949chevy »

There has been a few times when putting on the brakes jerked the steering wheel out of my hand and I headed back home very slowly to see what was up...I did observe that the closer I got to home...the less the pull was. It happened again a few days after that....same thing, steering wheel tried real hard to break my wrist. For a few days there was NO problem, then I washed the car and the problem returned. I took the 442 wheels off and on the R side, I had failed to put in the rubber stoppers. I was filling the drums with water and that will cause the shoes to stick to the drums. Found the rubber stoppers, installed them and no more pulling to the right after washing the car.

You cannot read something and assume its a good idea, that author may be talking drag racing...you need to seek advice like you did here from experience. The two reasons above by the poster should be taken seriously.
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