F series rear end disc brake upgrades

[bigmat]

is it worth putting it on a brake machine. mine only recorded 13% to the rears when we tested it. (r33 front, ma70 rear,1 inch master,bias valve)could be a good place to start to see the difference.

cheers mat

[bmxer54]

Sorry for reviving an old thread but im about to take on this same mod.
My plan is to use the rotors and handbrake backing plates off an mx73 with a yr22 F series diff.
From first look it seems it shall be fairly straight foward as it looks like it will all be fairly bolt up apart from custom caliper brackets and possibly needing custom handbrake cables

[LittleRedSpirit]

What bolts up if the calipers dont?

The rotors float, they dont exactly bolt on.

I have mx13 f diff with stock drums at this time, but I have looked around at the options.

If I were going to bother Id choose a decent caliper to begin with. You can get quite a few different rotors on the diff, U13 bluebird rotors slip on and have a similar overall brake system to basic s13 gear. They use a mechanical handbrake like an ae86 rear caliper.

theres a 269mm rotor off a cressida thats 4 stud that you can slip on also.

Caliper choice is the pain in the butt I think. You want a handbrake but you cant always set one up with certain calipers if you mix n match rotors and calipers where the drum handbrake is integral with the backing plates.

Im kind of leaning towards something like a wilwood multi piston type with a mechanical handbrake feature, as opposed to the internal drum systems many vehicles have, just for weight reduction and ease of adaption.

Unless your happy with basic single piston corona calipers you will probably be resigned to making brackets.

[bmxer54]

the backing plates look like they will be a fairly straight foward swap. and making a caliper bracket is easy. i did a similar swap on my hilux G series with ma70 calipers and handbrake setup. I figured i would go with mx73 and yr22 as i have the parts already and both the setups are F series . the rotors slide onto the axles perfectly i.e. centre holes are the same, i know thats not much. Though im sure if i need more than single piston in the rear i could source another caliper to fit my needs but a single should do the job at this current point in time.

Cheers Peter.

[LittleRedSpirit]

Yes Peter, I see how having these parts would make it a much easier starting point than for someone in my situation who has to find all the bits for whatever setup I use.

How is the handbrake on the ma70 rear brakes? Is it a feasable thing to use it in motion, or just for parkability?

[roadkill]

Hi,

yr22 is the tarago diff yes? You know they're crazy wide?

bEn

[Ken_T]

I have those three pieces at the laser cutter now. Pick up on wednesday hopefully for test fit. Uses an S13 caliper and disc and a twin piston wilwood caliper for hydraulic handreak.

[bmxer54]

Roadkill: I Realise the Tarago Diff will be rediculously wide, Its a good thing i already know which wheels i want and luckily have a wide selection of offsets.
LittleRedSpirit: The handbrake is purely for parking if i had planned to use it for drift i would install a hydraulic handbrake lever for that purpose.
Upon closer Inspection the backing plate inside hole is a little too small to so i will machine that out and then i can see where to go from there.

[bmxer54]

Well i got it all fitted up
This conversion was done using a yr22 F series diff and mx73 backing plates calipers and rotors.

The axles needed spacers before the bearings to push the flange further out (about 6mm) somewhat similar to the mx13 axle spacers.
I machined the hole in the cressida backing plates out to 81mm so they would fit over the tarago bearings and then drilled 4 10.5mm holes in the required spots using a handy little jig i had made.
I removed the handbrake cable retaining mounts and welded them to the bearing retainer plates.
The backing plates are held on using m10 x 50mm hight tensile hex head cap screws and flange nuts with 1 side flattened out the lock into the diff tube (could have got away with 45mm length studs and std toyota locknuts from the inside) .
I then butchered the mx73 rear trailing arms for the caliper mounts and welded them to the diff flange in the corresponding point to the backing plates.
The stock corolla handbrake cables fit in the mx73 backing plates.

A bit of custom work involved but it can be made to work
Here are the pics



Cheers,

Peter