I'll explain the performance gains and mpg gain first.. But first, the turbo whine, and waste gate sound pretty loud, with the both the windows open or shut. People with definitely be able to tell you've got a turbo. Mind you it won't sound like a Civic with an intake, because it is a little quiet but the turbo spool and waste gate pressure release are definitely loud.
perfomance - Acceleration, and throttle repaonse have some moderate improvement over the stock air filter and intake. HP and FT/lbs TQ have been gained, but because I have no access to a Dyno, I can only assume at least 3-10+ HP and 5-12+ TQ. With this improvement the car definitely has greater pull, especially on the highway.
MPG - after fiddling around with the setup to have the air filter itself as far away from heat as possible (mind you I do not have a heat shield yet) I got it set up to where it's pulling in decent air as you can see in my photos. The EPA rates 42mpg on the highway. On a 64 mile highway trip at 65mph, no AC on, my average was 48.1 for the trip, with a highest of 50.0 over 25 miles, 44.0 over 50miles and an average of 46.3 over 450 miles. As for city driving, roughly 38mpgs, and a city/highway average of 43. Please understand, I did this on 89 octane fuel, and did averages of 2 full to empty tanks. With the AC on ECO and fan speed 3-4, the average was between 35-43 mpgs and that of course, is city, highway and combined tests.
ECM/Computer - upon installing the intake which went really smoothly, the only thing thrown off was the MAF sensor. Due to it has a very close proximity of measurements for air intake and temperature. (I can only assume this as I have read the MAF sensor does try to keep measurements and temperatures steady). Do not worry fellows as the MAF corrects its measurements on its own, and usually within 1-3, maybe 4 days the check engine light will shut off as well. I have been running my Cruze with the intake set up above for a month now, and have not seen any further signs of engine malfunctions, thrown codes, or check engine lights.
Part numbers - I ordered my parts from summit racing, as they distribute the aluminum and not the ABS plastic found at the wonderful local auto zones and advanced autos, etc etc. the filter I chose to use is the Red Spectre Racing Filter which is $19.99 at autozone or wherever. You will only need one 3in to 3in coupling to connect the MAF adaptor and the 22 or 45 degree angle tubing, whichever you may choose. The MAF adaptor is part number 9405. I used the 45 degree which is part number 9749.
