Front Brake Upgrade: RX7 4 Piston caliper and 276mm Rotor

[Oly AE86]

AE86 Brake Upgrade Using RX7 FC3S Calipers.

Items required:

Brake Calipers, 1990 Approx RX7 Series 4/5 Turbo $135 Calipers, $160 to rebuild
2001 Mini Cooper S Rotors, 276mm dia, 22mm thick, 64mm centre hole (same as AE86) DBA P.N. 542 RDA P.N. 7352S (slotted) $285 Pair
Custom made bracket to fit Calipers to AE86 Hubs
4x M12 x 30mm Cap Head Bolts
8x M12 x 35mm Cap Head Bolts


First, brake adapter bracket.

Using CAD drawings from Twinky on Toymods , brackets are milled from solid steel on CNC. These were made cheaply by some guys at work, but with the drawings I think any fabrication shop could do it. Cad drawings are available

Free Viewer/Printer for DWG and DWF >





Second, modify Mini rotors



The rotors have a chamfer on the inside where they locate on the hub, a new chamfer needs to be made on the opposite side to fit over the AE86 hub, this can be done on a lathe in a few minutes.





Third, modify Sprinter hub



Because the disk is so much larger, I replaced the standard M10 bolts that mount the disc on the hub with new High Tensile M12 items, to the holes on the hub were drilled out to 10.2mm, and re-tapped at M12. Then, using the AE86 hub, re-drill holes in rotors to mount onto reverse of hub, PCD is about 87mm but having the old rotors and hubs you have a template.






Then, assemble the whole setup. Original AE86 brake lines can be used, or replacement braided units (ex. From AJPS $180) sweeten up the system. Original master cylinder can also be used, with a T-18 rear end my pedal felt a bit squishy at first, then firms up. Nissan Skyline R32 non-ABS is now installed and pedal feel is much firmer and stronger. Master bolts onto original booster and I bent original hard lines to suit. Had to shorten one hard line and re-flare but it wasn't difficult. Passed QLD Mod plate test with ease, stopping from 60km/h in 19m with Bridgestone RE001 195/50 Tyres.






Clearance is good with 15’’ SSR wheels, about 1cm to the outside of the rim. There is a clearance issue with the spokes so I ran a 7mm spacer. Currently running Watanabe RS 15 x 8.5 -6 and running an 11mm custom spacer. Wheels without dish or wheels designed for more modern cars (Rota Grid 16x8 +10 for Example) fit without any spacers.

[NIZLAH]

Awesome write up Oly.... the easiest and clearest guide I've come across so far..

[dr1ft-pig]

good article man, props

[Oversized 86]

good write up...however i think your prices are alittle wrong...

the calipers are definately more than $160 to rebuild...

[AE71briskev]

hey there does ne one have a set of these not on there car yet in brisbane my uncle owns his own cnc machine company and i can get them made up for next to nothing for me hehe

[Oly AE86]

When I had my Calipers rebuilt, its was $80 per. That included new seals, rebuild labor and cleaning/painting, pistons were prefect.

[Oversized 86]

thats bullshit cheap hey...
how long ago did you have that done?

[Javal]

Generally speaking, the pistons are the expensive part of having your calipers rebuilt. If they're fine, It's a cheap exercise like it was for Oly. If they all need replacing, the bill gets quite large.

[Oversized 86]

mmm...thats probably why the rebuild of mine cost well over $300

[Chrisso]

Hey Oly. Cheers for the write up again. I was looking for it but obviously deleted when the old boards went. If you want them for reference Hen sent me an updated version of files based on your drawings/design. I haven't looked at them yet, been otherwise occupied, so I don't know what was changed.

Chris.

PS. Cost me $80 for two rebuild kits from PBR, took a couple of hours to clean (most of the time), paint and rebuild.