The Vortech Standard Fuel Management Unit (FMU) is designed for use on multi-point electronic fuel injected engines. It is a secondary fuel regulator that installs in series with a stock regulator on the return line to the tank. The unit increases fuel pressure in proportion to boost pressure (this assumes the pump being utilized is of sufficient pressure and flow to deliver the fuel required). All Vortech FMUs feature CNC machined, 6061-T6 aluminum construction and a blue anodized finish.
The 12:1 FMU is standard in many Vortech systems. It is suitable for most applications running with original equipment injectors to maintain an air-to-fuel ratio of approximately 10.8 to 11.5:1 under boost. The pump utilized needs to provide sufficient flow to deliver the fuel pressure required in proportion to boost.
The 10:1, 8:1 and 7:1 FMUs are for Vortech applications that require less fuel pressure to maintain safe air-to-fuel ratios. The 6:1, 4:1 and 3:1 FMUs were designed for high-output custom applications where larger than stock injectors have been employed. For example, the 6:1 FMU can be used on Mustangs using either 30 or 36 lbs. per-hour injectors. The 4:1 unit was designed for either 38 or 42 lbs. per-hour injectors in the same application. Vortech FMU Recalibration Kits include a new ring, washer and fluorosilicate diaphragm.
Notes: For conversion from CC injectors, divide by 10.5 (i.e. 440cc injectors = 42lb./hr)
FMU calibration recommendation based on most combinations, and may need some adjustment (higher or lower gain) depending on modifications. Vortech does offer an FMU Needle Bleed Assembly (6Z120-010) that enables the ability to bleed of up to 1 point of gain from a Standard FMU calibration (i.e. 8:1 calibration can be bled down to 7.5:1 or 7:1), to help fine tune fuel requirements.
Recommended calibrations for commonly used injector sizes:
12:1 - 19lb./hr Injectors
10:1 - 24lb./hr Injectors (Cobra)
8:1 - 24lb./hr Injectors (GT/LX)
6:1 - 30lb./hr Injectors
4:1 - 38/42lb./hr Injectors
3:1 - 50lb./hr Injectors
