Dont. It screws up the calibration, and you will hurt, not gain, performance.
Best MAF are the stock ones. I got a Lincoln 80mm MAF and had Pro-M port the I-beam out of it and flow it. $200 for the meter and $125 for port/flow (with printed flowsheet).
Runs clean as a whistle and good to 1200cfm.
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Darius Rudis
Roadracer: Home built t-arm/panhard suspension powered by an S-trimmed motor :-)
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