Not sure which 2008 Hummer H2 Air Intake Systems are right for you? We have over 165 customer reviews, with an average rating of 4.5, to help you find exactly what you're looking for. George Y from Angleton, TX said, "Received the spacer in a few short days. Well designed and fits to the intake perfectly. No whistling noise heard when running.Power increase wasn't pronounced but that would need a dyno testbefore-and-after installation for measurement. Spacer is used in combination with cold-air intake and cat-back exhaust. Together made major improvement in acceleration."