Another ae86 brake conversion (fc rx7)

[twinky]

Hey guys I just completed my brake conversion on my sprinter. Using Fc Calipers and mini discs (retaining factory behind the hub setup). Thought I would post it up to help out (might get some rep points out of it )

Parts Required
Series 4/5 Rx7 calipers
2001- on Supercharged Mini Coopers Discs 276mm dia, 22mm thick (dba542).

Fitting

*The Mini disc is a almost straight bolt on with a 64centre hole. The only modifications needed are:

1. Redrill the holes to suit the back of the sprinter hub (easy with a drill press).
2. Because it is a fwd disc the chamfer is on the wrong side. This makes the disc not sit hard against the hub. There are two ways around this, 1. Is to machine a new chamfer on the other side or 2. What I did, machine the sprinter hub right to the very corner so it was square. Took 10mins on my mates brake lathe. Once this is done they are ready to bolt on.

* Now comes the fun part. The caliper adapter. I used a modified version of Hens caliper bracket he used with 180sx discs. The problem he ran into was the disc sat too far in and fouled the control arm. This is not the case with the mini disc which sits 5-6mm out. I made these in two parts to save on costs. I had the outside shapes water cut and then they were put on a cnc mill to machine the surfaces down and cut the recess and holes. Two extra holes were placed in both parts to insert dowels. Then I had them professionally tig welded, tapped the holes and bolted them straight on.

* The standard sprinter lines can be retained.
* Pedal feels good, but have yet to test as the car is getting painted and is half stripped.


I could make them for people in three options:
1. As is for around $350-400 depending on numbers (ready to bolt on).
2. One piece mild steel unit, Prob cost around $750-$800
3. In high tensile aluminium around $500 as a one piece unit.

Here is a pic of the adapter. I will get a pic of the finished setup when I have time. I think 15inch wheels will just fit. Have to confirm!

Hope this is of some help.

[1JZ-Rolla]

Nice work

Do you run RCA's? Disc clearance for me (nissan patrol 295mm disc) only became an issue once I fitted RCA's which moved the control arm outwards relative to the disc's diameter, where it used to sit nicely within the recess towards the centre of the disc.

[twinky]

Nah I dont run RCA's.

P.S did you run hub over disc (floating setup)??? The patrol disc has a huge centre hole 104mm

[Hen]

Awesome to hear it all worked. I'd been wondering how it ended up.

I vote this as a far better option than the one one I chose.

Hen

[mc68]

so many options, dont know which way to go!

wicked post man...its giving me ideas!

[oldcorollas]

very interesting... wonder how it would work with thinned nissan calipers? (larger piston area)

[1JZ-Rolla]

P.S did you run hub over disc (floating setup)??? The patrol disc has a huge centre hole 104mm

Patrol discs are only ~30mm tall (in total including the centre hat section), so they still bolted to the back of the hub, with an 8mm machined spacer (6 stud to 4 stud)

Any reason that people don't just buy Hoppers Stoppers' big brake kits for AE86? Seems that by the time you custom machine caliper spacers, source second hand calipers & rebuild kits, new hoses, etc etc then you're just about up to the same price anyhow......

[twinky]

1jz-rolla. I understand what you have done now. Seems like another option for running a largar disc. I wonder how a spacer would go down with an engineer though?



John

[1JZ-Rolla]

adapter is no problem, its already engineered

Just think of it as an aluminium hat on a DBA 5000 series rotor, except the rotor is stepped, not flat

[Rodger]

Does anyone want another set up like 1JZ-Rolla? A have another kit.

Nissan Patrol rotor on RA series hub and brackets to suit TN Magna caliper.

I ran his set up on my race car until I went to something else. Works a treat.

Regards

Rodger

[1JZ-Rolla]

Haha Rodger, I thought you might end up joining this thread

Hey, whats those funny looking things in your avatar? I think I remember seeing something similar in an automotive museum once

So Twinky: got some updated pics of the complete setup for us yet?

Cheers
Phil

[twinky]

Here ya go, not the best pics it was dark in the shed.



Cheers,
John

[1JZ-Rolla]

noice

they're a really flat disc hey! no problems with control arm clearance unlike mine.

[EDIT] must actually be the offset of the RA23 hub that causes the issues on mine, as from the DBA catalogue, your mini disc is actually 6mm taller than the patrol ones, even with my adapters taken into consideration.

[twinky]

Yep

mini disc specs:

276mm Diameter
22mm Thick
44mm Height

I can give anyone the autocad drawings. All you have to do is take the file to any place with a cnc machine and they should be able to put it into the computer and make them. Or if you lazy, I could do it for people around $350-$400 for a welded, taped, ready to bolt on bracket.

[oldcorollas]

hmm.. they are a fair bit lighter than the nissan 280x26/30 as well... 5.4kg vs 6.9/7kg....

what does DBA charge for them?