Holley Performance High Flow EFI Throttle Body - Billet Throttle BodiesPosted in How To on July 1, 2009
Engine performance is dependent on how much air and fuel can be taken into the engine and then fully combusted to produce power. While improving air flow into the engine can involve replacing everything from the air filter to the cylinder heads, one must realize that overall air flow can only be as high as the most constrictive part allows. After replacing the stock air filter and adding a few other hop-ups, the throttle body itself was now restricting the flow of air into our V-8 engine. Holley Performance had the perfect solution to our engine needs, suggesting we use their High-Flow EFI throttle bodies.
Holley makes performance throttle bodies (TBs) for a variety of applications including many EFI Chevys, the Magnum V-6 and the V8 found in '94-'01 Rams, '93-'98 Grand Cherokees, and '97-'03 Dakotas and Durangos. These beautiful 2x52mm TBs are CNC machined from 6061 aluminum billets and clear anodized. They are designed for mildly modified engines where the stock throttle body chokes the air flow to the upgraded performance parts. For instance, if your new intake manifold will flow close to 1000 cfm while your stock throttle body restricts air flow to 750 cfm, then that new manifold isn't going to be capable of reaching the improvements it was designed to achieve.
While the Holley High-Flow TBs will increase air flow at all rpm ranges, the most noticeable effects will be recognized at the lowest engine speeds. During these times, the butterfly valves that regulate air flow into the dual venturis are only slightly open, creating the most restrictive flow of the TB's operation. The extra flow provided by the smoothed out venturi entrances accounts for a larger percentage of the overall air flow. The engine is no longer as starved for air, more specifically the oxygen in the air, and the EFI system can spray more fuel to produce more power at these lower rpms
If you are replacing engine components with aftermarket upgrades, progressing from the filter to the intake valves, bolting on one of these Holley TBs is a logical step in that process. Likewise, if you already upgraded your engine with less restrictive components like an intake manifold and cylinder heads, then a Holley High-Flow EFI Throttle Body will release that pent up, power potential hiding within your engine.