Rear Disc Options for Floater Rear End

[rcmbronc]

Putting my floater rear end in my truck. I am using Schreiner 35 spline floater hubs with disc. I need to add calipers and brackets. I am looking at 4 piston Wilwood calipers with 1.75" pistons. Could also do a 3.15" GM single piston caliper. Any suggestions or others. Cant do a Explorer parking brake with this system so may do a mechanical wilwood brake caliper for that. Not sure.

Any other ideas or suggestions?

 

[Apogee]

I would think that you'd want your rear brakes to balance out with the front brakes, so in order to make any suggestion for the rear, we'd need to know what you're running up front. Unless you're running huge front calipers, I can't imagine why you would want so much piston area in the rear. Which "4-piston Wilwood calipers" are you considering? The Dynalite 4-piston calipers flex...a lot. Their Superlite 4-piston calipers are much better calipers in every way, but much more costly.

FWIW, the effective piston area of a 4-piston caliper with 1.75" pistons is 4.81 square inches. The effective piston area of a single-3.15" piston caliper is 7.79 square inches, 62% larger than the Wilwood unit.

Tobin

 

[SteveL]

I have the warn full floater kit on a 77 rear. It uses the caddy calipers. I never dialed in the e-brake. I'm in the middle of a hydro boost swap now. I'm thinking of putting on the bc caliper brackets on it to make em easier to bleed while we're in there. I have the same brakes n my 66 and like em. It has 4wheel disc with hydro boost. Lincoln calipers up front and caddy in the rear. Also a lbs valve from bc.

 

[rcmbronc]

I have T-Bird calipers up front. I think 3 3/32" diameter. The largest super light is 1.75" still which is 4.8". I am not sure how close the two need to match. Braking is not 50/50 so I dont know how these should be sized. I could also do Superlites no issue. Just a bit more money but still smaller than the GM calipers. I do see Currie and Camburg and others pretty much use the dyna lite in there rear kits.

 

[sykanr0ng]

Depending on what transfer case or rear output you have you might be able to come up with a transfer case disc parking brake for it.
Advance Adapters sells the PartsMike brake kits which work with the AA Dana 20 HD output and the Atlas TC:

http://www.partsmike.com/index.php/...brake---fits---atlas-std-shaft--hd-20300-kits

http://www.partsmike.com/index.php/...ake---atlas-and-hd-outputshaft-transfer-cases

 

[Apogee]

You don't want them to be equal, you want them to be balanced with respect to the front/rear brake bias. On a short wheelbase, high CoG rig, I'd be shocked if your rear brakes were contributing more than 25% to the overall braking equation at near maximum deceleration stops. If we assume roughly comparable rotor diameters, then I would aim for a rear caliper piston area around 1/2 that of the front calipers or less, so 3.77 square inches or less, which equates to a 2.19" [55.6mm] piston diameter. For reference, the Explorer rear brake calipers have a 1.89" [48mm] piston diameter and ~2.81 in^2 piston area.

If you go smaller than that due to caliper options and find that you want more rear bias, you could always reduce the front caliper piston area back down to the smaller piston front caliper. Personally, I don't see the need for the oversized front calipers and the hydroboost unless you just really like a super-light pedal and sensitive modulation. Brake pedal feel is largely subjective, but I prefer a little more pedal effort between nothing and brake lockup myself.

 

[ntsqd]

I would look at the DynaPro 4 piston calipers, they're one of the stiffest of wilwood's offerings and can be had with dust boots. These are a little big in piston area: https://www.wilwood.com/Calipers/CaliperProd?itemno=120-9701 but the next size down is probably not big enough.

 

[68ford]

I also have the schreiner floater set up. I run wilwood superlites and just welded 2 brackets per side. Basically 1 on each side of the mount ear on the caliper. Schreiner supplied the brackets.they we're a little long so I just cut some off and made a new radius in them. They may be too much for the rear of your eb, not sure. Mines 700 pounds heavier in the rear and I have a balance bar on my master cylinders so not apples to apples comparison.