TheAMCForum.com Homepage
Forum Home Forum Home > The Garage > Suspension, Steering, Brakes & Wheels
  New Posts New Posts RSS Feed - More disc brake discussion
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Click for TheAMCForum Rules / Click for PDF version of Forum Rules
Your donations help keep this valuable resource free and growing. Thank you.

More disc brake discussion

 Post Reply Post Reply Page  <12
Author
Message
2javman View Drop Down
AMC Apprentice
AMC Apprentice
Avatar

Joined: Aug/22/2010
Location: ohio
Status: Offline
Points: 98
Post Options Post Options   Thanks (0) Thanks(0)   Quote 2javman Quote  Post ReplyReply Direct Link To This Post Posted: Jan/15/2018 at 11:50pm
As far as the wilwood hubs, what spindles do they fit? The 69 drums or the later 80 concord? I was thinking possibly the wilwood hubs for the weight and ford ranger rotors (or ones at least as big stock) and looking for a set of calipers on ebay and making a bracket. I could always up grade to a better rotor later. As far as a caliper, as long as it will fit the around the Ranger's rotor (within reason) it will work correct? Wilwood's sight has the maximum size rotor thickness and diameter for their different calipers. 
Back to Top
farna View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar
Moderator Lost Dealership Project

Joined: Jul/08/2007
Location: South Carolina
Status: Offline
Points: 19611
Post Options Post Options   Thanks (0) Thanks(0)   Quote farna Quote  Post ReplyReply Direct Link To This Post Posted: Jan/16/2018 at 7:20am
Basically what you surmise in your first post is correct. Brakes are a basic hydraulic system. Dosn't matter what kind of pump (MC) you use as long as it provide enough pressure and volume to do the job. Same on the caliper end. As long as the caliper with pads fits over the rotor you're good there. The only thing is you want to make sure you have enough braking area, but I think you understand that!

I had to go look at the Scarebird site... So they have revised the AMC system yet again and now use Ford Sportrac rotors! They were using Toyota Previa, and before that Ford Ranger...  I guess it's good that they continue to improve the system, but there are four different Scarebird AMC systems floating around now -- the original with flat bracket that mounts behind the spindle, Ranger rotor with bracket that mounts on top of spindle, Previa Rotor, Sportrac Rotor...  Can't tell from photos, but Sportrac rotor model must mount the brackets on top of spindle, else it wouldn't work with drum and disc spindles.
Frank Swygert
Back to Top
Red Devil View Drop Down
AMC Addicted
AMC Addicted


Joined: Jul/10/2007
Location: Canada
Status: Offline
Points: 1743
Post Options Post Options   Thanks (0) Thanks(0)   Quote Red Devil Quote  Post ReplyReply Direct Link To This Post Posted: Jan/16/2018 at 7:34am
Wilwood's "AMC" hub is designed specifically to match up to their kits using an adapter-plate style mounted disc (disc mounts to rear of hub with an adapter plate).   If you go with a hat-mounted disc (disc fits over front of hub, mounted to a hat), it would open up more options, as long as bearing size and spacing and seal ID matches up, but gets into development of custom caliper brackets and more research and testing.  

Their kits were designed around the 71-74 Kelsey Hayes disc spindle, which uses the small bearing set (A2/A6).   if your spindle has same bearings and you can achieve the total combined thickness of (spindle flange + their caliper bracket) = 1.25", as specified in their installation drawings, their kits should fit. They include one spacer with the kit for thinner-flanged spindles, but other spacers could be used to achieve desired thickness or if too thick, machine the spindle flange thinner. 

If you have the 75-78 big-bearing spindles (set A16/A17), expect you would need to use A12/A13 bearings to fit their hubs (A12/A13 uses same cone as A16/A17, but different cups.   A12/A13 cup is same OD as A2/A6.   Wilwood changes bearing cups in their hubs to suit different applications with same bearing spacing, e.g. some GM vs Ford, and has different ID seals that fit same OD groove).   Would need to verify bearing spacing works, but there is a bit of tolerance here due to the way bearings are mounted and pre-loaded.  

For caliper, you need to pay attention to effective piston area vs master cylinder bore area, rotor effective radius, pedal ratio, boost and pad CoF compared to stock to achieve similar or better braking torque. Less torque needs higher effort to stop and may not be adequate.   Too much torque may lock-up prematurely. 

Hope this helps,RD


Edited by Red Devil - Jan/16/2018 at 7:43am
Back to Top
2javman View Drop Down
AMC Apprentice
AMC Apprentice
Avatar

Joined: Aug/22/2010
Location: ohio
Status: Offline
Points: 98
Post Options Post Options   Thanks (0) Thanks(0)   Quote 2javman Quote  Post ReplyReply Direct Link To This Post Posted: Jan/16/2018 at 12:33pm
Okay, yes very helpful information thank you both. As far as the spindles I have 1 set of 69/drum and 1 set of 80-81/concord disc, neither of those sets are the "big bearing" correct? The 69 are A2/A6? What bearing does the 80-81 spindles use?
Back to Top
Red Devil View Drop Down
AMC Addicted
AMC Addicted


Joined: Jul/10/2007
Location: Canada
Status: Offline
Points: 1743
Post Options Post Options   Thanks (0) Thanks(0)   Quote Red Devil Quote  Post ReplyReply Direct Link To This Post Posted: Jan/16/2018 at 1:12pm
Only the 75-78 were the A16/A17 ... and not sure if all during those years? Maybe just disc? Farna or one of the other more knowledgeable guys might know? I have one set from a '78 Concord that had the 2.6" piston Bendix calipers.

All other years use the A2/A6.

Wilwood has an excellent site with full technical details, so makes developing custom solutions reasonably straight forward. They have several hubs that could work, other than the "AMC" hub ... just not with their kits ... and need to sort through the details to suit your application.

http://www.wilwood.com/Hubs/HubProd.aspx?itemno=270-11942
http://www.wilwood.com/PDF/DataSheets/ds719.pdf

Hope this helps,RD.
Back to Top
2javman View Drop Down
AMC Apprentice
AMC Apprentice
Avatar

Joined: Aug/22/2010
Location: ohio
Status: Offline
Points: 98
Post Options Post Options   Thanks (0) Thanks(0)   Quote 2javman Quote  Post ReplyReply Direct Link To This Post Posted: Jan/16/2018 at 10:53pm
Ok great. Yes it does and I will post whatever I come up with. Thanks again RD
Back to Top
farna View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar
Moderator Lost Dealership Project

Joined: Jul/08/2007
Location: South Carolina
Status: Offline
Points: 19611
Post Options Post Options   Thanks (0) Thanks(0)   Quote farna Quote  Post ReplyReply Direct Link To This Post Posted: Jan/17/2018 at 6:22am
75-78 are big bearing, as Red Devil mentioned. All except 77-78 Hornet/Gremlin/Pacer are 3.1" piston Big Bendix calipers with 1.19" thick rotors, 77-78 small cars have odd-ball big bearing 0.88" thick rotors with 2.6" piston Bendix calipers.

I have never had Wilwood hubs, didn't notice that the rotor bolted on the back! Should have... just never looked that close at the photos. As long as the lugs are long enough and the hub diameter isn't too big I don't see why you can't use a hat style rotor with one though. Diameter of the hub can be turned down a bit if necessary without weakening the threaded lug holes. Aerospace uses a similar hub. Wilwood has hats and rotors for standard hubs (universal fit), just need to get one with the correct bolt pattern, offset, center hole diameter, and clearance for the hub. There would be some weight savings with the aluminum hub, but not a whole lot. An aluminum hat with steel or iron rotor on a drum brake hub would be an inexpensive combo that saves a little weight...
Frank Swygert
Back to Top
343sharpstick View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Mar/10/2010
Location: Wisconsin
Status: Offline
Points: 554
Post Options Post Options   Thanks (0) Thanks(0)   Quote 343sharpstick Quote  Post ReplyReply Direct Link To This Post Posted: Jan/17/2018 at 9:12am
I’ll likely be ordering some new parts over the next few weeks from Wilwood to start a mach-up of a setup using the following:
-     Wilwood AMC hub
-     12.72 Dia. “GT 48 Curved Vane Rotor” (PN 160-2540 & 160-2541).
-     Forged Superlite Internal 4 (PN: 120-11330 & 120-11329)
This is by no means an inexpensive option however, just the parts will be nearly $1,300. This doesn't include the price of the mounting bracket.

As an FYI, I’ve been in communication with Wilwood Support, and they have replied quickly with great information. I’m impressed. Working with a supplier that has this type of customer support is important when putting something like this together.

Edited by 343sharpstick - Jan/17/2018 at 10:17am
Back to Top
Red Devil View Drop Down
AMC Addicted
AMC Addicted


Joined: Jul/10/2007
Location: Canada
Status: Offline
Points: 1743
Post Options Post Options   Thanks (0) Thanks(0)   Quote Red Devil Quote  Post ReplyReply Direct Link To This Post Posted: Jan/17/2018 at 12:02pm
Someone added a model of a Superlite caliper to GrabCAD a while ago. May help. This was my mock-up with an 8 bolt 12.72" x 1.25" rotor (12.19" dia. x 1.25" would be a lower-cost option with more clearance and expect more than adequate with matched pad) using a 2.5" deep Coleman hat, stock big-bearing rotor turned into a hub, 15" x 10" stock car wheel w/ 275-50-15 tire, simple caliper bracket mounted to back side of knuckle and rear of wheel instead of front. Ray Larson mentioned in his "The Story of My Engine" that he spaced the steering arm away from the knuckle and seemed to have good success, so figured it wouldn't hurt geometry too much, got the rotor inboard for better cooling and more space for caliper and made the caliper bracket simpler.



That was when I was wanting to do some racing at the local 3 km road course ... but never got there. For street or autocross, a pad upgrade is generally enough ... but reducing weight would help on the track. For pads, e.g. a Porterfield R4-1 pad has an average CoF = 0.56, compared to parts store replacements typically 0.35-0.40. That's a 40% increase in braking torque, so needs some sticky tires and a well prepared track. Pads are key to a brake upgrade and on-track performance, but best to have a caliper commonly used in racing for more pad options and lower cost if racing much.

Hope this helps,RD
Back to Top
farna View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar
Moderator Lost Dealership Project

Joined: Jul/08/2007
Location: South Carolina
Status: Offline
Points: 19611
Post Options Post Options   Thanks (0) Thanks(0)   Quote farna Quote  Post ReplyReply Direct Link To This Post Posted: Jan/18/2018 at 7:21am
You were only spacing the steering arm 'in" the thickness of the bracket. Might cause a little tire scrub when turning real sharp, like all the way to lock, but that's about it. I have a little scrub on sharp turns like that with my T-bird rack and pinion setup. Oddly, it's most noticeable when backing -- I suspect due to the toe-in (or toe-out when in reverse). But not enough to affect handling (which is great!) or tire wear. 
Frank Swygert
Back to Top
 Post Reply Post Reply Page  <12
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.156 seconds.
All content of this site Copyright © 2018 TheAMCForum unless otherwise noted, all rights reserved.
PROBLEMS LOGGING IN or REGISTERING:
If you have problems logging in or registering, then please contact a Moderator or