Speed density is cheaper to set up and easier to tune if you can reprogram the computer. GM switched back to Speed density for a while on the TPI and LT-1 motors. For a stock car all the airflow parameters can be pre-calculated, thus no real need for the Mass air measurments.
Even a stock Mass air can compensate for a supercharger etc, much harder for a stock speed density.
Aftermarket systems that are speed denisty allow more adjustablitly, some custom setups have no space for a MAF meter etc...
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Frank W
90 5.0 LX coupe Daily driver. K&N filter. Flexalite fan, 3 core radiator. FMS flywheel and Clutch, FMS blue wires Energy Suspension end links, MAC 2.5" cat back FMS aluminum driveshaft, MSD blaster coil, MAC shifter
88 Notch 2.3L FOR SALE!
My two Notchbacks
74 Chevy Laguna Type S-3 305 Finally fixed getting a 454 to put in garage
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