Dyno Time

Without the plate installed, our Project FR-S produced 176.24 peak whp and 148.04 lb-ft of torque in its naturally aspirated state. After establishing the baseline, the plate was installed. The plate system adds a small amount of volume to the plenum. The FR-S spun the rollers again as we logged and monitored the changes in AFR. Power checked in about a half-horsepower higher with the plate installed.

Next, the 50-shot jets were installed. With the juice flowing peak power jumped to 228.5whp while the torque value breached the “200whp” mark landing at 209.51 lb-ft. Reviewing the AFRs revealed that the nitrous- oxide/fuel mixture was not only safe, but a bit on the rich side. To take advantage of this condition and optimize the system we replaced the nitrous jet with a “36” jet in place of the supplied “35” jet. While this should have only amounted to a gain of about 3.0 horsepower due to the increase in nitrous, the actual gain was on the order of 6.0 horsepower. This additional gain was from the increased efficiency at the slightly leaner AFR. The final result rang in at 234.56whp and 216.79 lb-ft of torque. For the price of a high-end exhaust system, the Nitrous Express kit generated power similar to a forced induction kit.

A 33% power increase leaves a large area between the dyno graphs.

Staged

Having quantified the power gains provided by the nitrous kit, we drove to the Irwindale Speedway 1/8th mile drag strip. Without the nitrous system activated, the first couple of passes were FR-S (Freaking Really-Slow), taking 10.35 seconds to crawl through the traps at 65.85 MPH. Opening the bottle and arming the nitrous system shortened the elapsed time to 9.34 seconds and increased the trap speed to 79.26 MPH. This left us Feelin’ Really Satisfied.

The NX bottle warmer keeps the bottle pressure constant

The Final Word

Nitrous-oxide injection systems can provide inexpensive, safe and reliable power gains. However, the amount of nitrous oxide and additional fuel injected must be reasonable. Just as running too much boost on a stock engine and driveline can wreak havoc, so can configuring a nitrous system to deliver more power than your driveline can handle. While the plate system for the FR-S/BRZ can be jetted to support close to 200 additional horsepower, doing so on a stock engine and driveline is STUPID! Beyond a 50-shot, be prepared to find the limits of the factory clutch, factory fuel pump and the engine itself. Unless you have money to spend on such a development effort, stick to what we’ve proven can be safe. Then the only worry you’ll have in this relationship is how often you need to fill the bottle.