FAQ's

Why the BOOST-A-PUMP™ and not an inline or intank pump? 1. Inline and intank pumps aren't adjustable for flow. They're fixed. 2. The BOOST-A-PUMP™ is only activated during boost when the injectors are wide open so fuel isn't re-circulated to the tank and heated. Fuel starts to boil at 95°F. 3. The BOOST-A-PUMP™ is also a regulator. It adjusts for battery/alternator/accessory voltage variations. Every 1 volt = 10% pump capacity. 4. It's easier to install.

What size fuel pump should I use? Check out the Kenne Bell Fuel Pump Sizing Table and Fuel Pump Tech. Pick a pump that is adequate for your injectors. Use this formula: Injector size (lbs/hr) X .8 X number of cylinders X .6 = pump size in L/HR

What will give me the most "bang for the buck?" A supercharger. If you want the most torque, HP and launch from a traffic signal or at any engine speed, there is nothing better than the instant and full boost of a positive displacement supercharger.

How does a 50% power increase from a supercharger compare to a larger engine? Your engine is fed with approx. 14 psi (weight of our atmosphere). Take a 300" engine and give it 7 psi of supercharger boost - everywhere - and it will think it's a 450" or 50% larger engine . Remember, engines are merely pumps. The additional 7 psi boost makes 21 psi total (14+7=21) thereby forcing 50% more air into the engine at any time in boost.

What if the fuel octane drops or I need to lower my boost level? We have pulley selections for all our kits in 1 psi increments. For weekend racing competition etc. boost can be raised with a simple pulley change. An accompanying increases on fuel octane is usually necessary.

Can I increase my boost? Yes, but we don't recommend it. All our kits are designed to run on premium 91-94 octane fuel.

How many OEM's use the positive displacement superchargers? The Eaton (Roots style) and Twin Screw are offered by Ford, Aston Martin, Jaguar, GM, Toyota, Nissan, Mazda and Mercedes. Then there's the Ford Lightning, 2003 Cobra, '05-'06 Ford GT and the '07 up Shelby GT 500. We believe the trend is definitely toward the Twin Screw. The Mazda Millennia was first, but it was Mercedes Benz who raised the technology bar by selecting the Twin Screw for the higher HP models - and the Ford with the fabulous Ford GT. Today the eaton TVS 2.3 is popular with OEM's but we've never heard of anyone ever replacing a turn screw with an Eaton Roots type. That should tell you something about superchargers.

Will I need to change to a lower gear ratio? Lower gears reduce fuel economy, increase engine rpm and wear and are costly. The "lower gear trend" was popularized by the Mustangs with centrifugal superchargers. The lower gear ratio allowed the engine to rev up more quickly. However, the gears do not increase boost. One of our test cars is an old 1990 Mustang with 2.73 gears. We installed 3.73 gears and it didn't improve 1/4 mile times. But get this - with the supercharger, you could launch the car in 2nd gear with the 3.73's and it turned the exact same 1.4 mile speed. See what torque (twisting force) does for you.

How is it possible for one supercharged engine to make more horsepower yet accelerate slower to 60mph and the 1/4 mile? Example: For each vehicle you must plot 1. the HP and torque at 2000, 2500, 3000, 3500, 4000, 4500, 5000 and 5500 and 2. the time spent at each rpm increment. The vehicle that spends the most time with the highest average torque wins. It has to. More torque (horsepower) means more twisting force to the wheels and therefore quicker acceleration. Again, peak HP is not the most important number for optimum acceleration. The engine spends relatively little time at 5500 - or whatever rpm it develops peak power. You wouldn't buy a cam based only on a peak HP number, would you? Warren Johnson's peak HP cam specs aren't for your Mustang - and certainly not your F150 with automatic trans.

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