The headers shown are RX7-405 SEC.
The "SEC" stands for ceramic coated. Ceramic coated headers last longer, and the ceramic coating acts as an insulator, which reduces some of the heat radiated from the header.
Headers now come with V-Band clamps and more efficient collectors.
RX7 FD (19931995 models), These are LS1 longtube headers, for use with Hinson LS1 V8 kit.
Will only fit cars using T56 transmissions.
Will not fit cars using 4L60-E transmissions.
These headers are installed from the underneath the car. The front tires need to be about 20" off of the ground, and the spark plugs should be removed during installation.
Some cars may require hammering the transmission tunnel/floor for header clearance.
The spark plug wires should be changed to 45 degree connectors for better clearance. Mustang 5.0 engines use 45 degree connectors.
These headers will also fit the RX7 LS1 FC model (1986-1991) using the LS1/6-speed. These headers will not fit cars using the 4L60-E transmission. The RX7 FC heat shields will need to be trimmed for these headers to fit.