Austin-Healey Replica Forum
You are not currently logged in and therefore do not have permission to view the full site. Please log-in or register. Not registered yet? Become a member of the Austin-Healey replica forum to access all of its features and disable advertisements.

Rear Drum Brakes

View previous topic View next topic Go down

Rear Drum Brakes

Post by DrJ on Thu Mar 12, 2015 8:57 am

Slowly transitioning from drivetrain mods to the rear end. Since I am relocating the emergency brake handle to the outside of the transmission tunnel (make way for the future console) I needed to run new e-brake cables. This gives me an opportunity to freshen up the rear brakes in general. Not wanting to change over to disc (not interested in pulling the axles) I hope to improve the function of the drum brakes by reducing fade. I ordered a new set of finned drums to replace the original's. Considering drilling small holes in the drums (and to rebalance) to permit the gasses which form during hard braking to escape thereby reducing fade. I will replace the rubber section of brake hose where it transitions to metal tube at the axle with braided hose to reduce the swelling tendencies under high pressure. Will flush out the existing hydraulic fluid and replace with DOT 4 or if I can convince myself that it will do no harm, silicone based fluid which would not wick up moisture over time reducing it's boiling point.

Lastly and to the point of my question, I would like to replace the basic organic shoes (Pt.# 151's) with semi-metallic. Semi-metallic shoes off gas considerably less than organic. So far I have not been able to find them and they may not exist. Has anyone found semi-metallic?

Documentation on my MX is sketchy but what I do have seems to indicate that the brakes (10"drum, 1 3/4" wide shoe, 5 bolt pattern) came from a 73 Maverick or a 74 Mustang II.

Any suggestions?

Paul

DrJ

Posts : 129
Join date : 2014-06-19

Back to top Go down

Re: Rear Drum Brakes

Post by Hermn8r on Thu Mar 12, 2015 6:37 pm

If it is a 8 or 9 inch there is an easy swap from a rear disc from a ford explorer. Removing the axles are easy just 4 bolts and slide them out. The explorer rear disc have the brake calipers brackes built into the backing plates. I am planning to do this myself but have not gathered the parts yet.

Hermn8r

Posts : 49
Join date : 2014-10-12

Back to top Go down

Re: Rear Drum Brakes

Post by David V. on Thu Mar 12, 2015 7:40 pm

Where did you find the finned drums if you don't mind me asking? Smile
avatar
David V.
Admin

Posts : 490
Join date : 2014-05-27

http://healeyreplicas.forumakers.com

Back to top Go down

Drums

Post by DrJ on Fri Mar 13, 2015 9:51 am

Hermn8r: Good to know. I had read that the current master cyl. would be inadequate with a transition to disc, what u think?. Cost as always, plays into the situation. This Healey will be used as a daily driver and cross country cruiser, probably rarely see a track. It's the usual argument that although drums are inferior to disc (at least in there present form), it is a 2,300 lbs car, the front discs are providing most of the stopping power and money can be spent to improve those as well. If the drums fade propensities can be reduced your probably good to go. And yes I am scared-ed about opening up the differential pumpkin.

Dave: You can ask me anything, no worries. The drum I ordered on speculation (measurements look close) came from Centric Parts, pt#: 123.61002. They have not yet arrived but it was 30.00 on Amazon, free shipping.

Now since my initial post I found the site of Muscle Car Brakes, based in Texas. They sell ceramic shoes that will fit a Ford 10" drum, 1.75" friction surface. Additionally they sell a composite drum that they clamed runs 150-175F cooler under braking. They also sell a higher volume cylinder that biases more pressure toward the drum and does not require a change of master. All things considered this would seem to lead to better engineering of a antiquated system while being a simple bolt on experience.

Going to think on it for a few day's, see if anyone else has an opinion. I'll post the results when I pull the trigger.

DrJ

Posts : 129
Join date : 2014-06-19

Back to top Go down

Re: Rear Drum Brakes

Post by David V. on Mon Mar 16, 2015 4:29 pm

DrJ, please let me know how this setup works out, especially if the drums fit, as I would probably do the same for a few years until I can save up for a LSD Diff with vented discs. I thought finned drums were only found on vintage Alfa/maserati GP cars, did not know they could be purchased for American cars. Also pretty interested in the upgraded pads.

If you're replacing the e-brake anyways, I would consider a hydraulic e-brake setup, requires much less tugging and is much more powerful!

I envy the British Sebrings which come standard with Jaguar Independent rear suspension and inboard discs (no wheel clearance issues).

My issue with brake upgrades is that if I'm going to really put money down, I want a big difference/much bigger discs, which would not clear my wheels, which means an additional spending spree on wheels and tires. I also quite like my current wheels. Finned drums and better pads in the rear, and maybe some drilled rotors and better pads in the front might satisfy me for now though.
avatar
David V.
Admin

Posts : 490
Join date : 2014-05-27

http://healeyreplicas.forumakers.com

Back to top Go down

DrumBrakes

Post by DrJ on Tue Mar 17, 2015 9:41 am

I will keep you posted. The drums should be here this week at which point I will order the ceramic shoes. Picking up new brake cylinders today along with some DOT 4. From a technical point this will be better than what I had and should be satisfactory for my kind of driving and at low cost. As we all know hobbies such as these have an unlimited capacity to absorb money and I am early in the process. For me it is all about return on investment. When I get to the front end the first order of business is fabricating and installing the anti dive brackets Terry Crist was good enough to help me with. Investing in better disc brakes here would provide a more noticeable improvement I think, something I will need to research. Overall I have no plans to race her, just "spirited" driving and better front discs with improved rear drums is probably going to be fine. Will not know for sure till I get her back on the road this Spring.

DrJ

Posts : 129
Join date : 2014-06-19

Back to top Go down

Re: Rear Drum Brakes

Post by Sponsored content


Sponsored content


Back to top Go down

View previous topic View next topic Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum