Rear disks

[briankk]

A few years ago, I bought a disk conversion kit for my '89, got around to trying to install it, couple of weeks ago. Take off drums, hub and backing plate, install caliper holder, install '74 chevy disks and calipers, and Bobs your uncle...
Didn't work out that way, the caliper adapters weren't for anything remotely like a D70, bought so long ago I couldn't remember who to complain to. Bought another set of caliper adapters from Great Lakes Offroad and started over.
Bolted 'em in, bashed the drums off and the disks on, mounted the hub, but the caliper isn't anywhere near centering on the disk. GLO mentioned that some applications might require a spacer of 1/2" or so, seen pics of this on Pirate 4x4,
but I need spacer a couple of inches long, not good. I need either a caliper adapter with a big jog in in it, or a disk with a lot deeper hat. Local AP stores useless. GLO says they are researching it, and I guess they are still doing that.
So, heres my question: Do any of y'all know where to go for a jogged caliper adapter, or a '74 K20 disk with about 2" more hat? TIA..

 

[RSchwarzli]

That sounds all like a mess.

Only thing I can think of is a Willwood rotor with a deeper than normal hat. They have many many sizes and in theory would solve your issue.

 

[briankk]

A mess indeed. GLO suggested longer bolts on spacers of some kind of tubing, would causie a flexible arm in the rear brakes.
I've sketched up a spacer, 1.75" thick, that will do the same thing. but is well supported. Now just need to find a machine shop to make it for me...
Meantime, old drums going back on.

I've had some tell me that my problem is that my axle a a Dana 71, is why the stock stuff doesn't fit, but I think the higher pinion offset for the 3.07 rear end ratio has little to do with axle tubes. But this wouldn't be my first logical failure, either..

 

[RSchwarzli]

May I suggest some pictures? I will admit, I am a little lost on what you are describing.

 

[briankk]

I'll give it a try. First, I try to figure out how to use Gimp...

 

[briankk]

This is a test, to see if I can upload pics.. seems I can. this is stripped RR D70 (71?) on my truck. The flange with lighter colored rust is mounting surface for drum backing plate, or upright to support the caliper, if using disks.. More to come.
Why yes, I did torch off the ebrake cable..

 

[briankk]

This is Great Lakes Offroad caliper adapter, with mounted '74 K-20 front caliper, $20-something down at Autozone. This adapter will also take the late'60s-early '70s Cad ElDorado caliper
(D-52,style, I think they call it). $70 something at AZ, but it has a parking brake. Cad pads are too thick for K-20 disk, so you have to attack Cad brake pads w/belt sander...
This is proper mounting position for this application, to keep bleed screw on top of caliper.

 

[briankk]

Here's the problem, if you can see it, sun's going away..
This is K-20 disk mounted to Dodge rear hub. Notice that the caliper, back there in the shade, is BEHIND the disk, not really what we were looking for.. The caliper is at the proper height, though.
Requires either about a 2" spacer behind caliper adapter, or about 2" adapter ring between disk and hub, but I doubt that there are wheel studs that long manufactured.
FYI, chev disk is 1/4" smaller dia. than Dodge front disk..
What a PITA. Shame I can't find a deeper hat...