Comparing boosted Mazda Miatas from all four generations

Photography by Travis Ingram

Norman Garrett served as the design engineer for the original Miata, but early in 1990 he left for another OEM. Two and a half years later, he explains, he launched his own line of reasonably priced Miata superchargers:

In the product plan for the P729 project, aka the Miata, we recognized that the customers might want more power, but that putting more power in at the OE level would trash the insurance rating. At the time–1985 or so–the Honda CRX Si was getting terrible ratings from the insurance companies due to its power. Some teenagers were paying hundreds of dollars a month for insurance, and this affected sales.

So, we thought ahead for the aftermarket as a way to get to the higher power levels. One idea was to nest a supercharger in where the power steering pump was located on the left-hand side of the engine. Superchargers (Roots and Lysholms) work great on track cars because the power delivery is so linear, and the kind of power they deliver is more in line with the character of what the Miata was about–less drag racer, more road racer.

Around 1992 to ’93, I saw that only a few turbocharger kits were being offered, the best being the BBR system that was factory-warrantied in the U.K. Corky Bell had a great turbo kit here in the States, and Bill Cardell followed suit. All of these kits cost over $3000, which I thought was a shame since that was too expensive for most owners.

I remembered our idea of a supercharger option from my Mazda days, and once Eaton had established themselves as a great OE supplier, I approached them to see if they made a blower small enough for a sub-2.0-liter engine.

They did not, but said that if I guaranteed to purchase 50 units per month and paid all the tooling and engineering costs, they would make a smaller supercharger just for me. I asked for exclusive rights to the aftermarket for all Eaton supercharger applications, and we struck a deal. Sebring Superchargers was born, and I asked racer Jim Downing to be the front office. Rob Ebersol did our logo and ad work.

I designed the first kit as a drop-in product with OE quality–no drilling, etc., required for installation–and priced it at $1995. The kits ran 6.0 psi of boost, added 40 percent to the horsepower output, and only took one Saturday morning to install.

We tested and obtained approval from the California Air Resources Board, then made kits up through the NB generation.

They sold like hotcakes.

We also developed kits for the four-cylinder BMWs of the time–3 Series and Z3–plus prototyped units for 5.0-liter Mustangs and GM 5.7-liter V8s. I approached Oscar Jackson and we put together a great kit for the Civics, then Preludes and other Hondas, sold under the Jackson Racing name.

We grew quickly and got to the point after a few years that the business became too large for us to manage without hiring on a lot of people. Holley came to visit and made noises about purchasing us. In the end, Moss Motors made an overture and we sold the lot to them, and Oscar sold them the Jackson Racing name at the same time.