Against the advice of others and my better judgement, I put the MIT on my truck with the "o" shaped TB gasket, and after the computer had time to reset, I noticed a little more pull lower in the RPM range. I'm not so keen on the roar of the intake, but it did seem to perk the truck up a little. I think that we seem to get better results with intake mods at altitude than the guys at sea level. I've been told that a super charged truck at 6000' makes the same horsepower as a naturally aspirated truck at sea level, so I say every little bit helps.....even if it is very little.