This 3/4" clutch master cylinder kit for the NA/NB Miata is our go-to upgrade for all BMW transmission packages.

The BMW slave cylinder require a larger capacity master cylinder to operate effectively, since the stock Miata master is only 5/8". 

This kit includes a modified Wilwood 3/4" master cylinder, reservoir, steel firewall adapter, fittings, and a clutch line that pairs with both setups mentioned above.