| King of B-Series Manifolds The Omni-Power Pro-4 sport injection "was designed for the serious enthusiast and professional racer to maximize their engine's horsepower, torque, and throttle response," says Steve Rothenbuehler, owner of Omni-Power. Rothenbuehler developed this product keeping in mind the design experience he gained when completing intake manifold development for two well known companies, both of which currently offer aftermarket Honda intake manifolds. Rothenbuehler purports that this product is different: "Unlike many of the typical OEM based manifold designs on the market, the Omni-Power Pro-4 sport injection incorporates an independent runner design and independent runner length adjustment. These unique features are based on years of professional engine building and racing development experience."
What's so cool about independent runners? By separating the cylinders, more power is realized as each cylinder draws air independently. Compared to a plenum style intake manifold found on most engines, all the runners are drawing air from one area - the intake plenum. Even the best plenum-style manifolds in the world can't distribute equal amounts of air into each cylinder. The runner length adjustment can be independently changed in 5 mm increments. This provides users the ability to tune their manifold length for a particular rpm range and engine size - where other manifold designs are fixed in length. Fixed length manifolds force tuners to use only 1 set of harmonic frequency scavenging points in the rpm with no adjustment for engine size, stroke lengths, modifications, or rpm requirement changes.
Serious, all-out race motors can correctly tune intake-scavenging frequency to header lengths - providing optimum cylinder fill for each individual cylinder. The throttle plate was placed closer to the intake port than other brands' models to increase over all throttle response. Omni-Power uses large 53 mm throttle plates that pull air through full radius air horns for maximum flow. A carefully designed tapered runner increases the velocity of incoming air and also provides an optimal venturi point. The Omni-Power manifold velocity is so efficient that it actually requires up to 15 percent less fuel to make more horsepower under wide open throttle than other brand manifolds.
What may seem to be an oversized throttle plate actually is not. The open throttle plate surface area, surrounding air boundary layer and runner taper design, were all taken into consideration by Omni-Power for determining throttle plate size.
Omni-Power Pro-4 sport injection manifolds also accept the following OEM sensors and ancillaries for easy bolt-on installation: TPS, MAP, IAT, throttle cable, fuel rail, injectors, brake booster vacuum, and fuel pressure regulator vacuum. No other after-market B-series intake manifold incorporates all of these features collectively. A low-restriction filter is included with each manifold to keep foreign objects from entering the engine. Omni-Power recommends using a TPS/ALPHA-N based fuel management unit, however after-market software for stock MAP-based systems will function satisfactorily with proper tuning also.
To illustrate how well the Omni Pro-4 ITB worked we tested the manifold on two engines. The first test was performed on a fully-built Type-R engine with 0.5 mm oversized pistons with a 11.5:1 compression ratio. The head was ported and polished and the cams were upgraded to Buddy Club Spec IV. The intake manifold was a ported Type-R intake manifold. The combination was good for 231.0 hp and 151.3 lb-ft of torque to the wheels on a Dynapack chassis dyno. With the Omni Power Pro-4 intake manifold installed and tuned, the engine generated 245.0 hp and 161.3 lb-ft of torque - an increase of 14.0 hp and 10 lb-ft of torque over a ported Type-R manifold. The largest increase was witnessed at 9100 rpm redline with a gain of 20 hp. The key to the Omni Power ITB is the ability to fine-tune the runner lengths to engine combination. Prior to tuning the intake lengths, the engine generated 237.2 hp and 156.0 lb-ft of torque to the wheels just by bolting the manifold on. After we tuned the runner length we were able to gain an additional 7.1 hp and 8.3 lb-ft of torque to the wheels. Our second engine was Rage Racing's 2.1-liter race engine that currently powers their all-motor drag car. The engine is equipped with a 13.5:1 compression engine that has a fully ported and polished cylinder head and upgraded camshafts. A ported Type-R intake manifold was also used on this engine combination, and was good for 253.8 hp and 183.7 lb-ft of torque to the wheels on Rage's Dynojet. With the tuned Omni Power ITB installed, the engine generated 260.3 hp and 186.5 lb-ft. Peak power was increased by 6.5 hp and peak torque by 2.8 lb-ft. The majority of the performance gains were realized after 8200 rpm - where the Type-R manifold starts to quickly lose steam and the ITB really shines. The ITB generated an additional 15 to 20 hp from 8600 rpm to redline.
Although the world might be a better place if one size fit all - not all things are created equal. The same goes for performance components: just because one product works well on one vehicle doesn't mean it will work well on another. The Omni Power Pro-4 ITB proves that one size does not fit all, and that the key is fine-tuning the manifold to work with your engine combination.
Key FeaturesIndependent runners for optimal cylinder fillingUnique independent runner length adjustment in 5 mm incrementsUses OEM sensors and ancillariesTapered design runner for maximum velocity, fuel atomization and cylinder filling Full radius air inlet hornsLarge 53 mm throttle plates (biggest B-Series Throttle bodies on the market) Close placement of throttle plates to intake port for improved throttle responseAir filter includedIndependent air correction on each cylinder for a smooth idleUses OEM fuel rail, and stock or after-market injectorsSimple bolt-on tune and race design15%+ more fuel efficient under wide-open throttle10%+ lower average brake specific fuel consumption over CNC ported ITR or similar manifoldOutperforms all other B-Series manifoldsSeveral patent pending features