I currently have an '06 C6, Z51, M/6, convertible. So far, I have installed a Blackwing air filter and Melrose headers. I was wondering if there would be any noticeable power gains if I added a Granatelli Mass Air Sensor to the mix. What is your opinion and what, if any, gains could I expect. The car is primarily street driven with occasional dashes down the quarter-mile.
Michael Oswald, Philadelphia, PA
I should probably use a politician's approach to this question and use a few hundred words in an answer that doesn't say anything. But that would ruin my image, and, besides, I haven't gotten much hate mail since all the Crossfire owners came to their senses.
The direct answer is you may get a noticeable power increase from an aftermarket mass air sensor, but I wouldn't install one. The concept behind these sensors is fine: they're larger in diameter than their stock counterparts, and, therefore, offer less restriction to incoming air. That should translate to better performance, but air flow isn't the only consideration. In the case of a mass air sensor, it must also provide accurate air-flow data to the PCM or ECM. The problem with the majority of aftermarket mass air sensors is that most are not properly calibrated. So even though they offer higher air flow capacity, they have a negative influence on overall performance because the air flow data they send to the PCM is incorrect. Personally, I don't know of anyone who has installed an aftermarket mass air sensor who hasn't removed it (because of degraded performance) and reinstalled the stock sensor.
The term "degraded performance" is usually interpreted as a reduction in power output. That's not always the case. In many instances, installation of an aftermarket mass air sensor will result in an increase in peak horsepower. Unfortunately, that increase is frequently accompanied by drivability problems, erratic part-throttle operation, and a reduction in fuel economy.
I've done some preliminary testing that has provided enough data to document that this legitimate problem exists. I'm currently expanding the scope of these tests, and in the not-too-distant future, you'll see an article in Corvette Fever with all the relevant facts and figures.