The combustion is also much different than the OE chamber. It’s got more of a kidney bean shape, as opposed to the heart-shaped stocker. It’s also designed to “improve airflow and flame propagation”, which leads to increased power and torque. Again, we’d have to say that our numbers bear out the claims. It also bumped the compression up a bit, from 10:1 to 11.41:1—we had to back our timing off by 1 degree, but still made great power on California’s tepid 91-octane gas.