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Just released our new 1" Wilwood brake master cylinder kit "MCK" for the 90-05 Miata. A few updates from our previous kit:
- All metric fasteners - non-ABS compatibility - Remote reservoir option for turbo cars - Lower price!
The kit comes complete with everything you need to perform the swap. OEM master is 7/8", Sport Brakes are 15/16". The 1" master trades a slightly higher pedal effort for less pedal travel. The result is a firmer pedal which improves modulation and makes heel-toe easier. A must have for autocross or track duty.
I would have been very interested in this had it been available when I put in my 15/16" master. This option is much more attractive than monkeying with adapting 1" masters from other cars. Even my 15/16" factory master required some light tweaking of the hard lines, which it looks like this kit would avoid.
Is there a reason why you couldn't/shouldn't pair this 1" master with the large non-Sport booster from later NB2s and stock 1.8 calipers? It seems to me that that combination could net a nice short pedal stroke with very reasonable pedal effort. It could be a functional, economical setup for a street-driven or autocross car where someone doesn't need the power and heat capacity of a big brake swap, but still wants improved pedal feel. You'd of course still want to have the appropriate pads for whatever kind of driving you're doing.
For reference, I was pleased with the results of moving to an MSM (Sport) booster and 15/16" master on my '99's stock calipers - it gave me a shorter stroke and similar pedal effort compared to stock. By my back of the envelope calculations this 1" master would reduce the stroke another 12% and increase effort about 14% compared to my setup. You could get that pedal effort back down (and then some) by using the biggest booster (or bigger brakes).
In an attempt to clarify the factory brake booster options, according to Keith Tanner and my googling when I was shopping for mine, there are three different ones:
1990-00: 4.74:1 <- this is a bit approximate, as Mazda gives a range of output pressures as acceptable 2001-05 non-Sport and Sport with ABS, except for MSM: 9.7:1. Yes, that's about double. This booster is visibly fatter, and I suspect it has dual diaphragms inside instead of a single. 2001-05 Sport without ABS and MSM: 6.4:1
Pedal effort is of course affected by brake size, booster size, and master cylinder size, among other things. Given variables like driver preference of pedal feel, intended use, ABS or no, and level of grip from the tires, it seems to me that there could be benefits to mixing and matching different brake parts with this new master cylinder.
Is there a reason why you couldn't/shouldn't pair this 1" master with the large non-Sport booster from later NB2s and stock 1.8 calipers?
No reason that wouldn't work just fine. You just want to use a high performance brake pad. Stock or OEM replacement style brake pads won't develop enough torque.
Is there anything else needed to fit this to a RHD car?
Unknown. Master fitment and basic hydraulics are the same. The question would be where the hard lines on your RHD car are in relation to the M/C. If the same relationship and distance as LHD, then it'll work. If your prop valve or LF hard line junction is a lot father away than the LHD version, then the hoses will be too short. My guess is you are OK, but we can't know without a RHD car to test fit on.
Post a clear, well lit pic of yours showing termination points for all hard lines leaving the M/C
12-22-2021, 01:18 PM
1" Master Cylinder Kit @ Supermiata
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