Nice project. I'm intrigued by these cars and the new Miata. I may need a long distance commuter in a year or so.
Some suspension upgrades and the addition of a turbocharger made our Scion FR-S project more enjoyable, but we wondered how much the stock exhaust held us back.
That search led us to JBA Exhaust and its cat-back system for the Scion FR-S, Subaru BRZ and Toyota 86. Retailing for $512.50, this cat-back exhaust—part No. 30-9030—is built completely from stainless steel and is said to be easy to install.
Before installing the exhaust, we put the FR-S onto the dyno to get some baseline numbers. After a few pulls, we averaged around 246 horsepower and 223 lb.-ft. of torque. (That’s already 46 more horsepower and 72 more torque than stock thanks to the turbocharger.)
JBA says its cat-back system is a simple bolt-on upgrade. We found that to be true, though we did have to shorten one pipe due to our turbo install. In total, the job took under an hour, but it could have taken even less time had we not stopped to take pictures and video.
The exhaust installed, we rolled the Scion back onto the dyno and were surprised at the results: The car now made 263 horsepower and 240 lb.-ft. of torque—a total increase of 17 horsepower and 17 lb.-ft. of torque—with most of that extra power available from 2500 rpm all the way up to 7300 rpm.
A closer look at the dyno graph also showed that we made more boost for a longer amount of time across the power curve. Boost came in at around 2500 rpm, with the turbocharger topping out at 13 psi of boost at 5800 rpm.
Bonus: The JBA exhaust weighed 8 pounds less than the factory system and improved the sound of our FR-S without making it much louder than stock:
Nice project. I'm intrigued by these cars and the new Miata. I may need a long distance commuter in a year or so.
I had a co-worker who added a Rotrex turbo kit for his track build. The transmission was a weak link. I worked with him for a year and he replaced 2 transmissions in that time. He wasn't running a lot of boost either, just what the kit provided. I'm curious to know what your solution will be.
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