Who's done FC/RX7 brake conversion

[Frak]

ha ha I can better that, cost me around $250 to do whole lot(before changing pads and included re kitting with genuine Mazda kits) and I think about 8 years ago!

[Kid Karola]

I have fitted the AJPS adapters, EG6 Civic discs, Series 6 FD calipers, braided lines and Motul RBF-600 fluid. IT's 200% better then the JDM slotted AE86 setup I used previously. Haven't fitted a larger MC yet, but have updated the proportioning valve to the latter 2 piece item. I'll probably fit a Willwood bias adjuster when I fit a 15/16 or 1" MC such as the R32 item mentioned to fine tune the brake balance.

The over-hub is not necessarily a bad thing, with under-hub Civic discs I needed a 12mm slip on spacer to clear FD calipers with my neg offset SSR mesh and 6mm spacer to clear with 15x8.5 Equips I test fitted.

Jazzy J's rotors being FC are 276x22 for those of you playing at home.

[truenoboy]

I'm actually located in the US, so I don't have to worry about the exchange rate. I've been trying to research as well as compare and contrast both the Willwood BB kit vs. FC brake conversion.

Here's my dilemma in deciding. I'm running a 3sgte with a t3/t4 in my AE86. Soon (in the next couple of weeks) I plan on turning the boost up to 20psi and pushing around 400 rwhp. That said, the 2 main things I’m trying to factor in my decision is cost and whether or not the upgrade will have enough stopping power for 300-500 tq

[Kid Karola]

From memory the piston size in the Willwood calipers is 38mm... can someone confirm? which is about the same size as FC/FD (Series 4-6 later had staggered pistons and wider discs), but the Willwood calipers are slightly lighter.
The pad size and friction area is also very similar, but the slightly larger discs on the T3 kit will be an advantage as you have more area to distribute heat. The 280x25mm discs are probably about the same weight as the 261x22mm Civic ones given they are 2-piece and have an alloy hub - it seems the new version is a one piece as pictured below would be similar in mass to the Mini item.
Also remember that you'll need decent tyres to match those brakes, so street tyres are only going to limit you. R-compound will give you more mechanical grip in accel and decel. And if you're doing a brake conversion replace those old front bearings.

T3 Willwood conversion "Big Brake Kit"


A mate here in Norway has just purchased these for his GZE propelled Corolla GT



Will give you impression when he gets it going (the motor has just been rebuilt)

[Frak]

Ok, Aussie FD RX-7 SP's(homologation for 12 hour racing, very rare) ran RZ calipers and discs, staggered pistons and 32mm thick disc, 312mm diam , these are also the same as JDM RZ and Series 8. Some series 7 FD's have the caliper to suit 22mm thick disc BUT staggered pistons(stops pad taper) this is what I used, hunt some down if you are doing this conversion.

Series 4-6 suit 22mm thick disc and all pistons are same size. good caliper

From Series 6 they introduced a new casting technique called "squeeze casting", basically it makes the calipers lighter but the material is more dense thus making it stronger = less flex.

all RX7 4 piston calipers are made by sumitomo.

If you are very lucky and hunt the jap wrecking yards you may come across a set of rare sumitomo Mazdaspeed RX7 calipers, these have staggered piston, suit a 32mm disc BUT have a quick release mechanism for the pads!

[truenoboy]

Hmm! I wonder if there's no rotors that already come 4x114.3 stud holes that will work with the FC conversion. Rather that than drilling holes in rotors. Also after reading through these replies, sounds like I need r32 master cyl, which brings up a new dilema for me. I'm in the US. We never got Skyline here in the states until now with the R35. That said, me getting my hands on a r32 booster is going to very difficult.

[buddyparts]

willwood dynalite kit for ae86 is $1500 lighter and better then fc and run standard booster

[Oly AE86]

Link to my FC RX7/Mini Cooper S Conversion guide

[Kid Karola]

The holes drilled in the disk are more like 4x78 (don't quote me on that!) as they still bolt to the underside of the hub.
There are a couple other Master cylinders that are almost exactly the same dimensions, Mitsubishi Starion and Nissan Patrol - ring any bells? I think there was was a whole thread specifically only on the master cylinders...

[LittleRedSpirit]

Wilwood kit is excellent. The rotors I got with mine were german made, and extremeley well ventilated. The Front 4 piston caliper was about the same weight as a rear standard caliper from my ae86 diff.

The bracket was chunky and if anything the weak point was the standard toyota pressed metal bracket that it attached to. If I persist with this exact setup I will get someting one piece made.

The brakes have seemed perfectly proportioned in all the testing Ive done. This required the ae86 2 piece prop valve setup to achieve. Previously with adm prop valve setup (well pressure limiting actually), it was too heavy on the rear brakes.

A new standard master cylinder works fine with this setup.

The main limitation with all of these upgrades is that they are on an ae86 strut. If it were something much the same but with a much larger stub axle, it would be a better foundation on which to have big brakes and tyres. If the forces are increasing that much, I want the biggest bearing I can get.

I cant comment on the other setup but it kills adm brakes stone dead.
Id say its probably much of a muchness. Like ajps said its wreckers parts for one, retail for the other. For me its only a problem when the retail isnt as affordable. If you are looking to create your own wild upgrade, have a look at the wilwood site, they have some crazy technical data there, and you may find they do a caliper that bolts right up, and has four pistons, weighs nothing and is gonna set you back 3-4 hundred delivered brand new if the exchange rate is good.