The Porsche 718 GT4 RS is already a track-focused machine — but with an Akrapovic slip-on exhaust, it reaches another level.

Ok, we've done header tests in the past, comparing various styles and sizes on moderate to high-powered street-style mills. In the case of the big-block Mopar, the default favorite tube size has long ...

No one around the shop could remember the last time we ran our 302 dyno mule, but it must have been five years ago. Fitted with a fresh set of AFR cylinder heads, the little beast started right up and ...

You may have seen Power Trip run mid-10s at Englishtown on the pages of GMHTP. That was through a 2.5-inch exhaust system. This thing makes big power even on pump gas, right around 450 to the wheels.

We’ve fitted our BMW E46 M3 with Supersprint stepped headers, full Supersprint exhaust, and paired it with a custom Evolve ECU tune — now it’s time to hit the dyno and see the real gains. This is the ...