Accessories: Alternator and Air Conditioning

The alternator and air conditioning compressor get mounted in near-stock locations and keep the swap Miata-friendly.

The simple approach to accessories is moving all the Miata pieces over to the FE3. The priority is making sure the accessories have pulley alignment with the crank pulley for proper drive. Next is addressing tension so the belts can be adjusted to drive the accessories.

My FE3’s crank pulley has two multi-rib sections. The alternator is driven from the crank pulley’s rear section. I’m using an alternator from an F2 engine since it fits and produces more amps than the Miata alternator. It’s mounted at the bottom to the stock FE3 alternator bracket which is bolted to the block. It uses the original FE3 armature at the top for tensioning. The arm was modified to mount a spherical rod end that bolts to the block. Electrical connection is the same as the Miata – plug-n-play.

The A/C compressor is stock Miata, 90-03 vintage – large and heavy. The compressor is placed in a similar position as it is on the Miata. This avoids any need to adjust the compressor lines.

A steel plate is bolted to the FE3 using bosses at the front of the block. Like the motor mount, the steel plate is drilled to accept the factory Miata compressor bracket so that it bolts up just as it would to the B engine.