I’d really like to have a less restrictive exhaust installed on my ‘91 MR2, but I haven’t been able to find headers that are certified CARB-legal. Where should I be looking for upgrades?

The stock exhaust manifold is very restrictive on the 2.2L 5S-FE 4-cylinder engine, resulting in only 130 horsepower. In addition to the stock headers, the intake manifold is also a severe bottleneck in power delivery. The intake runners are almost a foot long, optimized for low-end torque.

Pictured: stock intake runners via Ebay

I would like to build up the current motor in my car, but I’m not sure where to find emissions-compliant parts to do so.

Anybody know where to source something for this? My Google-searching isn’t getting me anything.

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