Click to enlarge58 MM ZZ502 Ramjet Throttle Valve

Dyno Testing of the stock ZZ502 Ramjet crate engine has proven to make much less power than advertised 502HP. The throttle valve that comes on the engine is a twin blade 48MM which is the same size originally used on the 305" TPI engine in 1986.

ASM's twin blade 58MM throttle valve lets the beast breath, with ECU calibration 50 plus HP gains are routine.

Our throttle linkage is the same configuration so the conversion is simple, your existing IAC and TPS sensors are re-used to simplify the installation.

The CNC machine billit housing is the standard of the industry, not some cheap cast housing that wears over time as the shaft rotates in the housing.

The centerless ground nickel plated throttle shaft rotates on oilite bronze bushing for long life and can be replaced if the need arrises.

Each throttle valve comes with larger throttle to plenum gasket and necessary hardware.

Our ECU program will complement the performance of the engine with the 58MM throttle valve, and remove the "Pesky" "Green Engine Rev Limit", Specify the desired rev limit when ordering.

If you don't see what you're looking for please call or e-mail us.

Phone: (480) 753-0208 Fax: (480) 753-0216

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