Food for thought from chefmoto

Yep, brake upgrades to discs all around have been all the rage on vintage iron for a while. Just as long as you have no problem backing up your ET by a tenth or two in the 1320, due to constant disc drag, as opposed to no brake drag from the drums. Old OE stock discs up front, are really all thats required to have pretty decent brakes on 99% of the old musclecars. And some smaller cars, still brake good even just with the bigger drums, as long as they are cool. I recall the different '71 340 Dusters I've owned, as all braking better even with just drums, than did my '72 Olds 442 with discs and a 455 up front, and also better than the 440 Challengers with discs up front that I had. Early Dusters with manual everything, are very light cars, and that's all it took. Weight to braking surface area and clamping force. Had a buddy with a '66 Chevelle, it only stopped so well, even with PB discs up front too. When I get this ol 440 van goin, I'm expecting to perhaps be after a rear disc conversion on it as well, but we'll see. I usually don't mess with brakes, unless they really stand out as being not adequate, which from my experience, has been localized to the older GM products I've personally owned. My 2000 SS had great brakes however, discs all around.

Deckers is kinda easy going, mountain biker, pedal power!come on up tp leadville and we can go pl,ay in in the rocks!10,000 feet up will make a healthy guy from sea level toss them cookies quick!

"Just as long as you have no problem backing up your ET by a tenth or two in the 1320, due to constant disc drag, as opposed to no brake drag from the drums"

I never experienced any ET or MPH differences when I converted my car to disc. Some master cylinders for disc brakes have a higher residual pressure valve than drum brakes because of the caliper piston area to eliminate the need for a "make up" brake pump.

Well, since caliper pads ride right at the disc, there is usually some drag. AS opposed to drums, in which the shoes pull far away from the drum, when brakes are not applied. Can't say I've had the conversion experience personally, just read about it for decades, on drum to disc conversion articles. I know every car I've had with discs, if you have a need to push the care at any point, you'll usually hear the pads just barely dragging the rotors. Yet, all drums, totally silent. I have had that observation, and on all perfectly functioning parts. Even heard it on bike disc brakes. I just accept it as a known possibility, but hey, if you get away without it, great, icing on the cake.