Low Drag Calipers for 72 [Archive] - Chevelle Tech

: Low Drag Calipers for 72


Stg'd 2Discover
Apr 28th, 09, 8:05 AM
Is there a low drag caliper from a later year GM that will work on a 72. I have already retrofited a takeup (stepped bore) master cylinder from an S-10.

If not ,who has experience with spring spacing the brake pads for lower disc resistance.

Tom

JWagner
Apr 28th, 09, 9:36 AM
This is an interesting topic and I suspect that you are the first to bring it up here. The master cylinder would be a necessary change as the pedal travel on the stock system seems a bit long to me.

blue66
Jun 22nd, 11, 12:00 PM
Anybody?

jeff swisher
Jun 22nd, 11, 2:06 PM
that is a good question,,I got lucky on 2 cars i have owned the best one was a 78 nova,,just over 400,000 miles on the original calipers .

i was going to change them because they had a bit of slack in them and would not hold pressure against the rotor ...was extremely easy to push,
Then it hit me,, leave it alone.
I could give it a small nudge when in the staging lanes and it would just keep rollin..and i watched all others push quite hard, with 2 people sometimes, on their cars....advantage goes to my wore out stuff.

another reason i will not go with rear discs in a drag car..

Something for me to think about....how to make them that way when new

Jack Action
Jun 22nd, 11, 2:20 PM
The «return spring» for a caliper is the piston seal. Careful design of this part gives the appropriate piston retraction.

The low-drag calipers must be used with the quick take-up m/c to be appreciated. Mixing low-drag components with standard components seems to be a bad idea. (see AlliedSignal alert (http://www.remanbrakes.com/pdfs/lowdragcalipers.pdf))

See p.5 of this Cardone m/c training (http://www.cardone.com/English/Club/Products/Brakes/Protech/Training/brake1.pdf) to understand how QTU m/c works.

As for identifying the low-drag calipers, it appears that the bolt spacing is the best indicator. There is a test proposed by Master Power brakes also; but I think this test only tells you if you have a QTU m/c or not. More info here (http://www.mpbrakes.com/uploads/documents/lowdrag.pdf). If the OEM m/c of a car is a QTU m/c (easily identifiable), then it also have low-drag calipers. Just find the model that fits your brake system.

Randy 67EC
Jun 22nd, 11, 2:49 PM
1981 Camaros & Firebirds have low drag calipers with quick-takeup master cylinders (power brake version only). Note the diameter on the back of the master cylinder is bigger than the earlier ones so you would need the booster from the same car. The calipers will bolt up to the Chevelle bracket (single piston style of course), the hose orientation may be a little different from what I have heard.

blue66
Jun 22nd, 11, 4:52 PM
Looks like alot of interchangeability in the D52 pad calipers.
Newer Astro vans use them also, up to 2002. I would think these would be using low drag calipers......Just need the metric banjo bolts.
Same cardone # for the 80-90's full size gm's.
Same 2 15/16 piston diameter.
I am already using a mid 80's manual brake s-10 master, so I should be good for the master......
I can't believe there aren't more poeple out here looking to free up the front brakes over the stock calipers?