Holley’s LT1-Style Mid-Mount Accessory Drive

By Rob Fortier – Photography by the Author

Holley just released their cutting-edge LT1-style Mid-Mount Accessory Drive for both small- and big-block Chevys this past year—and despite their claim it’s a complete system, it is missing one thing we’re all used to dealing with…brackets! That’s right, Holley used the LT1 ingenuity and incorporated that bracket-less technology into these kits.

Ok, in case you’re still scratching your head thinking, “LT1 accessory drives don’t fit on big-block Chevys!”, you’re right—an OE Chevrolet LT1 accessory drive does not fit an old 396…or any other big-block for that matter. That said, Holley’s new Complete Mid-Mount Accessory Drive Kit does—and the heart of their new system just happens to be an LT1-style water pump, to which the LT1-derived alternator, power steering pump, A/C compressor, and pulley/tensioner all mount off!

Holley’s Mid-Mount is so simple it’s pure genius. For starters, they’ve managed to group all the accessories in such a tight manner that nothing protrudes past the valve covers—and without a single bracket. And then there’s the alternator, which isn’t your ordinary LT1 knockoff, rather, Holley’s six-phase square-wave 150-amp Premium alternator (akin to what you’d find under the hood of a C7 Corvette). And Holley officially named both the big- and small-block Mid-Mount kits “Complete” for that exact reason: when you open the box, everything you need down the last bolt—as well as individual instructions for each component—is included.

Holley’s high-tech Premium 150-amp alternator simply drops into its mounting cradle location and is secured with the accompanying M10x80 button heads.

Using the proper installation tool (which can be rented from most popular chain auto parts stores), the P/S pump pulley is pressed on—and though it clearly isn’t (yet) in the photo, the center of the pulley should be flush with the pump shaft to ensure accurate belt alignment.

Taking two steps to the left side of the engine, with its innermost M8x95 flange-head bolt hand-threaded in (preloaded), the SD7 A/C compressor is set partially into the specially slotted mounting bosses on the water pump manifold. The other mounting bolt is then started halfway before the compressor can be rotated down and into the outer mounting boss.

Holley’s Complete Mid-Mount Accessory Drive Kit is without question one of the most innovative yet practical, easy-to-install front drive kit for old non-LS Chevy engines—and it works just as good, if not better, than it looks! CTP

Holley Performance

(866) 464-6553