Hi Way2Big,

The differences between what we do for a 77 mm versus an 87 mm depends on what happens when you install that part on that particular vehicle. Sometimes they run fine when warmed up, but spit & sputter when cold; other times they run poorly all the time, picking up detonation from too much advance from improper calibration, and sometimes they run just fine. Any number of symptoms is possible, which is why we say to see what happens when you bolt it on.

The manufacturers of these aftermarket mass airflow meters have always said, for years and years, that you didn't need a chip to compensate for them, they wouldn't cause any problems, and until a little over a year ago, we had to adjust the program for most of them, go figure. They just were not doing a very good job of calibrating them to the stock fuel injector sizes, and that's why they tended to cause problems that needed to be adjusted in the program.

Now, if they have properly matched the MAF to your injector size, then it should bolt on and work without causing a problem. Only time will tell if this turns out to be the case on your vehicle.

The MAF guy wasn't telling you not to use a chip because it doesn't work, he was telling you that his MAF isn't supposed to cause you to need to have your programming changed specifically for it. In the past that was very optimistic, but presently we find that about half the time overall, generally speaking, we don't have to make those adjustments, so it has gotten better over the past year or so. Only time will tell what happens when you bolt it on to your vehicle.

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Mike Troyer
Performance Products, Inc.
National Distributor of Superchips
(540) 862-9515
Email: mtroyer@compuserve.com
Performance Products F150Online Superchip ordering system: F150Online Superchip Ordering System
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