Disk Brakes (again)

[miket]

I've been toying with the idea lately. This morning I read a thread here which suggested Dales kit. I checked their site and the kit is over 1000 bucks. Nope!

The info on the kit says they used Mutt II calipers. So guess what I found on Ebay for $88. http://www.ebay.com/itm/151286673106?item=151286673106&viewitem=&vxp=mtr For the pair!!

Looks good to me, so I bought a pair. I had been looking at different calipers and realized the key feature needed was the E-Brake cable attachment. (I was supprised to learn that many vehicles have shoe brakes for the E-Brake. Dumb.)

So next I'll need a pair of rotors. I think the Topaz or the MII will do. Then I'll need a bracket. Summit sells these. They probably won't fit the Sunbeam axle, but we'll see. The caliper side will serve as a template.

Well it's winter and I'm dreaming about having my Sunbeam on the road. So if nothing else, the project gives me something to look forward too.

 

[Bill Blue]

Any idea what these things fit or the proper rotor thickness? It appears these are GM (metric?) rear calipers, not Mutt2. Several guys have installed calipers with a similar parking brake setup. They use just one brake. Simplifies things and they say it is sufficient. Don't know what an inspector would say.

I've gone down this road 3 or 4 times and it is relatively simple. Firmly mount the rotor of your choice, plumb an air compressor to the caliper, position the caliper and apply air pressure. The bracket is then fabbed up to fill the empty space between the bracket and the axle.

Should take only a few hours. Or, if your like me, a few months.

Bill

Oh yes, beware of wheel clearance if using 13" wheels. Tight little buggers they are.

 

[260Alpine]

In my opinion, Robbie's (socorob)Rx7 caliper on Contour rear rotor is a good setup. I was just looking on Rockauto and the 87/88 Tbird turbo rear caliper and rotor may be the very best for the Alpine/Tiger. The 10.9" front hub/rotor may work with the right bearings and races also. Here is a picture of the Tbird rear rotor and caliper on a Merkur IRS:

 

[Bill Blue]

Jim, do the Mazda and Tbird units work with the Alpine center pull parking brake? Can't tell from the pictures.

Bill

 

[260Alpine]

Bill, Yes they do. They are both about 10" vented rotors. The TBird rotor is thicker. Robbie ground a little off the Mazda bracket on the wheel side because the Contour/Mystique/Cougar rotor hat is pretty short. You could use a 1/4" spacer instead. I have a picture of that set up also:

 

[Bill Blue]

Hmmm. On the lookout (sorta) for replacement of my early 90's Saturn rears. They just do not have the stopping power to match the S10 calipers and 11" rotors up front. While tuning the engine at WOT, I use the brakes to load the engine. At about 3,000 rpm, the rear tires want to break traction, on a damp road road I can't hold them. I can only read that to mean there is little braking effort going on in back.

So the Saturn's have a 32 mm piston (803 sq.mm), Mazda 35 mm (961 sq mm) and Tbird 45 mm (1589 sq mm). Rotor's are (or can be) roughly the same diameter. Do I need twice the rear braking effort? Don't know.

Bringing this up mostly to show there are a lot of variables in the braking game. I'm pretty sure the Tbird caliper will be way too much when pared with the stock Alpine fronts.

Bill

 

[260Alpine]

Bill, I agree. The TBird rear would need larger front brakes also. The 87/88Tbird Turbo or 87-93 Mustang V8 front hub/rotors are 10.9" and would require a sleeve either on the spindle or in the hub for the inner bearing, the outer would use the Alpine race and bearing. I like the Nissan V6 D21 pickup twin piston caliper. 43mm pistons. Probably need a 7/8" master cylinder. It is for a 10.9" rotor. It is 3.5" mount spacing instead of the Alpine 3.25" spacing. It looks like a smaller version of the Camaro and Mustang calipers with a much narrower mount spacing.

 

[Bill Blue]

Don't mention front disc's. I don't think I'll ever dive down that rabbit hole again. Twice was enough, the front clearances are truly bizarre and ugly. This is the rotor I ended up with to mate up with the GM metric caliper. Lots of brain cells died in that effort and I have none to spare.



Robby said the RX7 fronts and rears were relatively easy and straight forward swaps. I think that taken overall, they would be best. Not the largest, but big enough for the Alpine and the set would probably be pretty well balanced. Certainly would be a better starting point than a parts catalog.

Bill

 

[260Alpine]

Bill, I followed yours and Robbie's threads. Like I said before, excellent backyard engineering!

 

[PROCRAFT]

brakes

Bill, maybe a proportioning valve for the rears if the pistons are bigger, more pistons more clamp force on the rotor, as to a single brake that's what we have on the Tiger Ford calipers on the rear, cable from auto zone with a clevis silvered on for the stock hand brake your probably right about inspections but, when is that going to happen, instead of fiddling around trying to find rotors the picture of the adaptor is the way to go that's what we did the kits we made, rotors are available everywhere in all sizes.

 

[260Alpine]

Robbie's Front RX7 front brakes:

 

[Bill Blue]

Bill, maybe a proportioning valve for the rears if the pistons are bigger, more pistons more clamp force on the rotor, as to a single brake that's what we have on the Tiger Ford calipers on the rear, cable from auto zone with a clevis silvered on for the stock hand brake your probably right about inspections but, when is that going to happen, instead of fiddling around trying to find rotors the picture of the adaptor is the way to go that's what we did the kits we made, rotors are available everywhere in all sizes.

I want to avoid proportioning valves. A large cylinder with a proportioning valve will not clamp any tighter that a smaller cylinder running at line pressure. Second, I am unsure of the effect of the greater brake fluid displaced by the larger cylinder. I ran out of MC volume using a 3/4" (dual piston) cylinder with the S10 calipers, had to go to 13/16" (dual piston). So, I'm on the edge. I don't know the full impact of using a larger rear cylinder, other than it will result in a lower pedal, which I do not want and I certainly don't want to go to 7/8 MC. Been there, done that.

The chances of an inspection in Indiana are zero, probably till way past our lifetimes. But we have guys living in other States and Countries. Some have pretty demanding annual inspections. So I just thought I would mention it.

Bill

 

[miket]

Bill, you're lucky. here the cars get inspected as thought they were going to be used as taxi's.
One guy with a Healey failed because the gear shift knob didn't show the shift pattern. Only in Quebec.

Otherwise great input here. Thanks.
Mike

 

[miket]

So Bill, can I take Dale's drawing for the bracket and simply modify it for the calipers I bought? Mike

http://www.sunbeamalpine.org/forum/showthread.php?t=15458&highlight=disk+brakes&page=2

 

[260Alpine]

Mike, Are the calipers you bought the Mustang II rear conversion ones? Those are actually Cadillac calipers and are huge and the E brake pulls forward. They are used with a Lincoln rotor and are meant for the Mustang II car when using 11" Granada brakes in front. You would be better off reselling those (Street Rods use them) and using the early RX7 solid disk setup where that bracket is a bolt on. Or modifying the top part of the bracket for the later vented RX7 Turbo setup that Robby did.

 

[Bill Blue]

So Bill, can I take Dale's drawing for the bracket and simply modify it for the calipers I bought? Mike

http://www.sunbeamalpine.org/forum/showthread.php?t=15458&highlight=disk+brakes&page=2

No, the drawing is for the Tiger. It used the Dana 44 rear axle and I seriously doubt the bolt pattern (or anything else) is the same as the Alpine's. Even if your using the Ford 8". Your going to have to fake it all the way. Not all that hard to do. Make a pattern out of single layer cardboard (like a cereal box). Transfer that to something more durable, say fiberboard, Masonite, plywood. Use that to actually mount the caliper to the axle. Then make the final steel adapter. Don't be surprised if you have to make several mockups.

But take Jim's advise and use a Mazda caliper. It is much more fitting for the car. I have a legitimate claim to being an expert on fitting brakes to the car. My first attempt at fitting disc brakes involved fitting Tempo fronts to the Alpine (in the form of the Ford 8") rear. Talk about a mismatch!

Whichever caliper you choose, the process is the same.

Bill

 

[Imperialist1960]

Disc Brakes

I've put a full system off of a 00 Mercury Contour V6 on my SII.
Only exception would be a 94 Nissan truck front rotor.

Still have to modify the parking brake actuators.

Mount the rear calipers in the horizontal plane, and not at 12'oclock if there is any part of the caliper hanging out in the vertical plane that the frame member is or the calipers will bang into the frame when the axle swings up, which is undesirable.

I'll do a write up of the project and submit it when the car is running around.

 

[miket]

Jim, I'm supposed to have the calipers Friday. I'll post a picture.

Bill. Good idea re the bracket template. 1/4" mdf should work well. Comes in 2' x 4' sheets at HomeDepot. So enough to do plenty of trials.

Mike

 

[miket]

I received the calipers and rotors this week and I must agree. the calipers are beefy.

I started to consider this project after I changed the pads on my daughters Altima. I was supprised to see that they were not very big and it seems that size might be suitable for this project. Then I realized the Altima used shoes for the E-Brake.

I've attached a photo that shows the parts I have and on the rotor you'll see the GM pad and an Altima pad.

The RX7 caliper seems harder to find so I've been looking at videos to try and find an alternate. This 01 jetta video seems to show a very suitable caliper. Certainly the e-brake hookup looks simple and the pads look far more reasonable in size

https://www.youtube.com/watch?v=YNYwEGNTQ1M&feature=em-subs_digest-vrecs
Comments welcome.
Mike

 

[Bill Blue]

Mike, I have no specific information, only some parameters to keep in mind.

If your going to use 13" wheels, rotor diameter will have to be less than 10". Mine are 9 5/8" and barely worked with 13" aluminum rims.

The Calipers that use the calipers for the parking brake all seem to adjust while applying the parking brake.

Have you tried buying rebuilt RX7 calipers?

Speaking of rebuilt, have you looked at Rock Auto? They have a lot of pictures and part dimensions and are an excellent way to check out the market. For example, they Show Mazda 3 and Cobalt calipers (about 2010) that look appropriate.

Bill