From a technical point of view, throttle response can be measured by how quickly your engine can generate vacuum in your intake manifold, through throttle pressure. The faster and higher the maximum vacuum is reached in the intake manifold, the greater the pressure differential between the outside air and your engine. This pressure differential forces air to flow from the high-pressure area (outside air) to the low-pressure area (engine and cylinders), and the greater the pressure difference, the greater the pressure force and pressure. faster airflow into the engine.

This is essentially how throttle response works. To improve throttle response, various engine alterations can be used to achieve a higher peak vacuum on the engine or a more rapid change in vacuum per throttle input… some of these include:

1- The use of undersized intake pipes and intake plenum runners to increase the speed of airflow in the intake system, making it possible for the engine to suck in all the air faster and create vacuum sooner.

2- Adjustment of the intake cam timing to open the intake valve as a maximum vacuum is created within the cylinder near bottom dead center.

3- Reduce the overall volume of the intake system, by using smaller manifolds, fewer vacuum lines, and more electrically (instead of vacuum) operated engine auxiliaries, meaning the engine has less air volume to remove intake system to create a vacuum in the manifold to force fresh air in.

4- Using cam gap and cam overlap (when intake and exhaust valves are open at the same time) for exhaust from the previous cycle to help draw in fresh intake gases for the start of this combustion cycle .

An interesting application of this concept is the G-Power supercharger kit for the BMW M3. The ASA supercharger-powered kit focuses on response and efficiency rather than jaw-dropping peak power numbers. The G-Power kit uses ASA’s very conservative boost supercharger that delivers a peak of just 4.4 psi of boost. Since the engine is already rated at a very high 420hp, adding just 4.4psi of boost results in over 500hp (as a conservative estimate) and up to 560hp as a result of this combination.

The focus of the G-Power kit isn’t just power figures, as rather than just providing a supercharger kit for the M3, G-Power has designed a completely new intake manifold for the M3. The manifold, while higher in volume than the original M3 manifold (for more peak power as it is now a supercharged car), has a narrow profile that promotes high airspeeds for improved throttle response. In addition, the new manifold has integrated individual runners for each cylinder complete with trumpet-style inlets raised from the chamber floor, which has been shown through fluid flow simulation to reduce limit pressure differentials, reduce droop of pressure within the intake manifold and promote higher air speeds which lend themselves to higher peak vacuums and faster vacuum buildup within the manifold.

Although centrifugal superchargers typically show a linear boost curve with engine rpm and therefore produce little power gain at lower rpm, the combination of this supercharger with the redesigned intake manifold and new adjustment provides a more than 20% increase in torque on ALL engines. rpms, and more responsive.

Here it is in G-Power’s own words:

Air duct: sports air filter system, CAD-FEM optimized flow boost recooling system consisting of an air duct made of cast aluminum, high-capacity air-to-air intercooler made of cast aluminum at the front of the car and a large-volume airbox made of aluminum casting, including 8 integral resonance induction tubes made of lightweight polyamide, which guarantees optimal throttle response and a perfect torque curve; engine load related boost control, pneumatically controlled; boost level approx. 4 psi rel.

The G-Power kit comes in 3 power ranges corresponding to 4, 6, and 7 psi of boost. The 7psi kit with its full titanium exhaust is capable of peaking at over 580hp with great response to match. Last but not least, the new G-Powered M3 is capable of doing a 0-124mph 2 seconds quicker than a factory M3, which at those speeds is roughly 20 car lengths between the two cars. Plus, the G-Power with its unlimited speedometer will keep pulling up to 223mph!