Special Ignition Timing
NEW ignition timing uses a special advance curve to increase combustion pressure and prevent the hotter and faster burn produced by Negative Pressure Supercharging and Hot Air Induction from igniting prematurely
NPS ignition timing
The NPS ignition timing uses a special advance curve that gradually advances the spark by 1-8° from idle to peak rpm and uses less advance. This allows the hotter and faster burn produced by Negative Pressure Supercharging and Hot Air Induction to produce more power and prevent pre-ignition (pinging).
However, the NPS advance curve works ONLY with the ignition timing at the crank shown below. This allows the faster burn and higher combustion pressure produced by NPS to work with high or low octane fuel and open or close chamber heads. Also, the ignition timing can NOT be advanced by more than 25° at the crank with the NPS advance curve because it will reduce power with the faster burn even if pre-ignition (pinging) is not audible.
NPS ignition timing at crank with 8 � 9:1 compression ratio
NPS vacuum advance
The faster burn produced by NPS needs less vacuum advance to prevent pre-ignition (pinging) and improve fuel economy. Therefore, during part throttle the total vacuum advance including distributor and crank advance should NOT be more than 45° with open chamber heads and 40° with close chamber heads.
|Impulse Engine Technology
PO Box 986 Randwick NSW 2031 Australia
Ph: (02) 9398 5544
Fax: (02) 9398 5644
International: Ph: +(612) 9398 5544
Fax: +(612) 9398 5644
Inventor of Negative Pressure Supercharging