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If you ever get to the point that you have definitive conclusions about how to get the BTV working safely, properly over the long haul, I hope you will announce it with a new thread.

This one reads like a soap opera, yet it is such a serious topic.

Discs are superior in fade resistance, cooling, stopping in wet condtions, ability to develop higher G force deceleration rates, easy pad replacement... all of which is pretty obvious to any competent mechanical engineer and virtually all automotive manfacturers worldwide, apparently. To portray drums as their equal simply because they can lock up the wheels is patently absurd, physics says otherwise. If one wants to retain them for authenticity, fine, but to defend them on scientific merits is a losing propostion.

Driving a near new '63 Ford wagon down the Mt Wasington auto road in '64 and losing 80% of braking power 1/3 of the way from the bottom of the hill convinced me of the advantages of discs, at least for those who are not desert dwellers or perpetual flatlanders, forever.

I run my 56 Executive with FULL stock drum brakes system EXCEPT for the Master cylinder. Run it at 80 mph for long distances in summer heat as high as 107 degrees F back in 2007. I have NO complaints whatsoever about the brakes on it. Fade is so slight to nonexisant at very high speed and requires conditions of near panic stop conditions. All of the brake shoes and other parts (not MC) were bought from Kanter some 15 years ago by former owner.

A 75 Comet i drove for 10 years Interstate hwy 90 miles perday every day DID have some brake fade that would occur toward the end of a exit ramp on very hot days. I knew it and drove accordingly. BUT that was a cheap car, NOT a luxury car.

Yes the disk brake is better than the drum. Marginaly so under EXTREME braking conditions. I would not call any disk i've driven superior to the Packard nor BIG Buick drums i've driven. Just marginaly better if any.

I have no complaints whatsoever about the brakes on my 56 Executive. Would never go to the efort to convert to disk unless parts for drum brakes became so expensive or obsolete that i was forced to a conversion.

If we consider only Packard (56's at least) then this drum vs disk is much like 6v vs 12v arguments. Just a lot of urban legend blown out of proprtion and confusing ford or Chevy standard models with top of the line Buicks, Cads and Packards.

To portray drums as their equal simply because they can lock up the wheels is patently absurd,

Randerson, if you were referring to my comments about locking up the wheels, please don't put words in my mouth, I DID NOT say that they are equal; advantages of discs for the reasons you state are obvious are not disagreed with. Whether those properties are needed in the manner in which we drive these cars is anothe matter.

Something i forgot to mention is that disk brake PADS and rotors do seem to have much longer longevity compared to shoes. Anywhere from 100% to 200% longer mileage life for the pads.

But the shoes are so easy to replace and relatively inexpensive that a conversion to disk is just not justifiable. Or at least not to me. I'll embrace just about any kind of conversion if it deems SIGNIFICANT benefit. Even an SBC transplant. Not there yet tho.

"Driving a near new '63 Ford wagon down the Mt Wasington auto road in '64 and losing 80% of braking power 1/3 of the way from the bottom of the hill convinced me of "

SO how fast were u going down the hill??? What was the posted speed limit???

PackardV8, I'll side a bit with Randerson on the issue fade. In terms of simple stopping power from a single stop, I suspect most of us have seen the Motor Trend data I posted a while back, Packard's stopping distance from various speeds was about the best of any of the 56 luxury cars. Yet, I've experienced fade in my 56 in continuous hilly conditions and had to remember my high school driver ed, use lower gear going down a hill if you would have needed it going up a hill.

Yes, I wish my Caribbean had better fade resistance. But for the kind of driving I do, and given my awareness of it, it's not been a real problem. I clearly believe the early Classic-era cars did have more competent brakes. As I've said before the brakes on my 34 Eight, though mechanical, are far superior. Huge drums and linings, variable vacuum boost from the dashboard control, and much more resistant to fade. I do wish the 56's had aluminum-finned drums and was thinking about talking to Dan Kanter about it when I see him Sunday.

I'm sure for typical old car driving, drums are fine. Just don't try to drive down big mountains or make repeated stops from high speeds or drive in a thunderstorm. O_D, didn't mean to put words in your mouth, but the way I read it I'd say you implied that if the wheels could be locked up by drums, discs had no real advantge, or else why mention it. Tires, though important, are not the sole determinant of braking/deceleration, however bias tires are inferior in that regard as well. I prefer any old cars I drive to have optimal stopping ability, which is why the BTV on my 56 Olds 98 will be replaced by a modern GM pb unit with discs behind wheels with best radials that will fit. If others are satisfied with original braking and tire equipment for reasons of authenticity, fine, that is their choice. But no way it can be supported on functional grounds, by any empirical standard.

PS the idea of finned drums is excellent as well, I remember the Buicks of the 50s were conceded to have the best domestic brakes when they switched to the aluminum finned drums.

On the MT Wash auto road speed limits, I can assure you that with my fear of heights I was going well under the limit... as to what that limit was, long since forgot - it;s been almost 50 years! No way I'd drive up/down that road today!

56Psckard400:

The problem is most likely a pinched or kinked or dented brake line. Most likely the brake line that travels across the REAR face of the rear axle. This can happen real ez if a jack is run under the car real fast and hard hiting the brake line. So look for a dent or collapsed section in the brake lines. Rubber hoses CAN be bad from the factory too.

If inspection of lines renders no problems then u'll have to pop each bleeder one at a time as i outlined above to find the offending section of the brake system to analyze further.