If you’re a Mazda Miata owner looking to add power to your roadster the choices seem very simple, you can either add forced induction, or drop in a larger engine. These tried and true methods may add excitement, but aren’t exactly special. When modding a car as popular as the Miata it’s hard to do something that is truly memorable. However, the guys at Garage Quinn Motors have done just that.
The white NB Miata featured on their YouTube channel features a truly impressive all motor build based on the stock bottom end of the Miata’s 1.8 liter four-cylinder. This build uses Independent throttle bodies and some other important engine modifications to produce 185 WHP from this heavily modified 1.8L four cylinder. With an increased compression ratio of 12.5 to 1 thanks to a ported and milled stock head, and the increased air flow, this engine is able to deliver its increased horsepower all the way to its 7,800 rpm redline.
Independent throttle bodies allow for quicker throttle response and increased horse power since the engine can now ingest higher volume of air. This means each cylinder now has its own throttle body to regulate air flow to the cylinders rather than sharing one throttle body between all the cylinders in the stock configuration. In addition to increasing the power potential of the engine independent throttle bodies also produce a very loud intake sound which is very noticeable in all the videos featuring this car. This modification allows naturally aspirated motors to intake as much air as possible without the use of forced induction.
This all motor Miata build is a classic example of the lost art of tuning a naturally aspirated engine. Instead of turning to forced induction to increase power which, is the default choice among tuners these days, the guys are Garage Quinn chose a unique path. This build proves you do not need a V8 or forced induction to build a faster Miata.