Good size MC for RX7 brakes?

[Jonny Rochester]

I got the AJPS brake adapters and assembled the kit with RX7 series 4/5 brakes etc... But I put it all on a friends car. I used my calculator and thought the stock MC would be the correct size, 13/16". But after a few days at the track my friend still says the brake pedal is way too soft.

From experience, what size master cylinder do we think is right for the Mazda 4-spot brakes? Assuming a totaly standard car has normal pedal firmness and travel.

And maybe running the standard MC with no booster is an option. (Is it legal for roadworthy inspections?)

[wideslider]

I had R32 4 pots with a disc rear end and had a Mitsubishi FTO master on it.
It was a 15/16 bore and gave a good pedal.

[Hen may possibly be a nut]

When I ran FC calipers I used a 15/16" master (and otherwise totally stock braking system, including rear drums). This felt fine too me, but I'm not the pickiest driver around.

Hen

[Matt-AE86]

Nissan R32 NA Master Cylinder (Non Abs)

[Skid Kid]

with booster, Starion 1inch

without booster, stock master

[Oly AE86]

I run the RX7 S4 calipers and use the R32 4 Door non-abs master. Definately firmer than the std AE86 item, but doesn't feel to stiff. I believe its 15/16 size, still using the std booster.

[af300e]

Got a feeling the r32 non-abs might be 7/8ths. So just a step up from 13/16ths.
I might be getting confused with the mirage master though...........will confirm (it's sitting in the shed).

[Vance]

i hear a mitsu pajero mc is the way to go. bolts up to the standard booster and isnt too long etc.

havent had any experience with it myself but its what JHS said to use in the FAQ. the part number on the FAQ is for the correct pajero mc to use. may aswell buy a brand new one

[Roo.]

yea i have the pajero master cylinder, got hilux brakes at the front and standard rear disk seems nice and firm pedal but i haven't done any hard braking yet

[StockAE86]

Nissan R32 NA Master Cylinder (Non Abs)

+1

I have one on my car, improved pedal feel greatly, and bolts straight up.

[Frak]

I run FD calipers, the master cyl is 15/16 and pedal is very good, not much travel.

[wideslider]

I have just finished the FC conversion and am running stock Master Cylinder.
Pedal is a a bit low for my liking which I feel is contributing to locking up the fronts under hard braking as I'm getting too much leverage in my pedal. (If that makes sense).
I would do one of the above master cylinder upgrades but as I have a JDM booster I will need to change it also, so it has gone in the too much effort basket for now.

[Tom86]

I use a Pajero MC 15/16 with stock booster bolt straight on, but need different fitting for one of the line. Very firm pedal but I think it could do with a bigger booster to give it a stock brake feel.

[Jonny Rochester]

15/16" Master is firm with RX7 calipers? Firmer than stock? If so, you should go to a smaller diameter master cyl to adjust this.

[Tom86]

but what 7/8 master cylinder can you get that will bolt onto stock booster? I have been looking for one for ages but have yet to find one.

[Jonny Rochester]

R32 Skyline. Some are 7/8".

[sonsta]

i just did the conversion, using stock and its a little to hard i think, and the pedal travels a little to far for my liking. not sure what master cyl i should use, and how much are they new?

[Jonny Rochester]

If the pedal travels too far (and it's not a bleed problem), you want a larger master cylinder. But this will make it harder also.

[sonsta]

yeh might even be a bit of a bleeding problem