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Negative Supercharging Ignition System

Produces 15-25hp more and 10-15% more fuel economy with Negative Pressure Supercharging

Negative Supercharging Kits and Impulse Crate Engines must use a HEI system
Power improvement produced by NPS HEI system
Fuel economy improvement produced by NPS HEI system


click to enlarge

Negative Pressure Supercharging High Energy Ignition (NPS HEI) system is the most powerful low cost HEI system available for V8 engines


NPS HEI systems 1-5 are low cost HEI systems that use spark amplifiers to produce 500 times more spark energy. This produces a lot more power and fuel economy than other HEI systems.

The spark amplifiers produce a huge plasma spark that draws a lot more current from the ignition system. This requires using a certain HEI module, coil and wires to supply the additional current without failure.

Therefore, the ignition system used with the Negative Supercharging Kit or Impulse Crate Engine should be upgraded with one of the NPS HEI systems.

NPS HEI System 8 x Spark Amplifiers 1 x Module 1 x Coil 9 x Wires Total Cost
AU$* US$
1 DirectHits Mopar Orange Bosch BIC290 9mm Spiral Core $590 $320
2 DirectHits Mopar Chrome Bosch BIC290 9mm Spiral Core $640 $350
3 DirectHits MSD-6A Bosch BIC290 9mm Spiral Core $840 $460
4 DirectHits MSD-6A Crane PS91 9mm Spiral Core $930 $490
5 DirectHits Crane HI-6R Crane PS92 9mm Spiral Core $1,170 $580
* Prices include GST

IMPORTANT - DO NOT use a ballast resistor with the NPS HEI system
If the vehicle is fitted with a single or dual ballast resistor either, 1) remove the ballast resistor from the wiring system and connect all the wires together, 2) connect a heavy duty insulated wire to each end of the terminals of the ballast resistor to bypass the resistor wire or 3) replace the resistor wire with a 3mm (1/8") steel rod or plate if you wish to keep the original look of the wiring and ballast resistor.

Negative Supercharging Kits and Impulse Crate Engines must use a HEI system
The larger volume of air pulled into the cylinder by Negative Pressure Supercharging produces a much denser charge. This requires a HEI system to fire the spark gap. Aftermarket HEI systems with 1 coil per engine or vehicle manufacturers HEI systems with 1 coil per cylinder produce the power to fire the spark gap with the denser charge produced by Negative Pressure Supercharging. However, these HEI systems only slightly improve power by 1-2% (5-8hp) and fuel economy by 2-5% (0.5-1mpg) in a 400hp engine. Also, vehicle manufacturers HEI systems with 1 coil per cylinder are 4 times more expensive than aftermarket HEI systems with 1 coil per engine.

For this reason we invested a great deal of time and money to find a powerful low cost HEI system that, 1) uses 1 coil per engine, 2) produces more power and fuel economy than vehicle manufacturers expensive HEI systems that use 1 coil per cylinder and 3) will survive with the huge plasma spark produced by the DirectHits spark amplifiers. After years of testing many different combinations we found 5 NPS HEI systems that are low cost and produce a lot more power and fuel economy than other aftermarket and vehicle manufacturers HEI systems.

Power improvement produced by NPS HEI system
NPS HEI systems 1-5 produce the same 4-6% (15-25hp) improvement in power at full throttle. However, during part throttle the multi-spark ignition of NPS HEI systems 3, 4, 5 produce more towing power and fuel economy, smoother idle and acceleration, easier starts and less emissions than the single-spark ignition of NPS HEI systems 1 and 2.

Fuel economy improvement produced by NPS HEI system
NPS HEI systems 1-5 produce a 10-25% (2-5mpg) improvement in fuel economy which pays for itself after 13-26 months. The additional 10% fuel saving produced by NPS HEI systems 3, 4, 5 is achieved with multi-spark ignition which burns fuel more efficiently at part throttle than single-spark ignition. This allows the carburetor to use 1-2 steps smaller primary jets and a leaner air fuel mixture of 14.6 - 14.9 at idle and cruise without compromising driveability. However, the air fuel mixture at full throttle should be kept at 13:1 for maximum power.

NPS HEI System Increase in Fuel Economy (%) Money Saved per Annum* Recover Cost of Ignition System Upgrade Performance per Dollar
1 10 - 15% $300 - $450 16 - 24 months 3
2 10 - 15% $300 - $450 17 - 26 months 5
3 20 - 25% $600 - $750 13 - 17 months 1**
4 20 - 25% $600 - $750 15 - 19 months 2
5 20 - 25% $600 - $750 19 - 23 months 4
* Based on a $3,000 annual fuel bill
** Best performance per dollar and value for money

Spark Amplifiers
DirectHits spark amplifiers are a revolutionary breakthrough in ignition technology. Instead of producing a narrow spark at the plugs like the HEI systems used by the aftermarket and vehicle manufacturers, the spark amplifiers produce a huge plasma spark that generates 500 times more spark energy. This ignites a larger area of the air fuel mixture in the combustion chamber which produces a lot more power and fuel economy than today's HEI systems. The spark amplifiers screw onto the end of each spark plug, one is required for each cylinder and they work ONLY with non-resistor spark plugs.

Module
Use one of the HEI modules shown above. However, other HEI modules may be used and should survive with the DirectHits spark amplifiers. Therefore, use the HEI module fitted to the vehicle but if it causes misfire replace it with one of the HEI modules shown above. DO NOT use the Mopar black module or standard modules used with early model vehicles. They are NOT HEI modules and will misfire or burn out with the spark amplifiers.

Coil
Use one of the HEI coils shown above. Most other HEI coils will fail with the DirectHits spark amplifiers but some HEI coils may survive because we have not tested every coil. Therefore, if your vehicle uses a different HEI coil than shown above, check out the list of coils we have tested so far that misfire or burn out with the spark amplifiers. Coils Tested with DirectHits

The Bosch BIC290 coil is the only low cost HEI coil (AU$50, US$20) we have tested so far that will survive with the spark amplifiers for more than 12 months. However, during hot weather the Bosch coil may run slightly hotter than the Crane coil. If this happens use 2 Bosch coils and connect a spiral core wire from each coil to the distributor. It will reduce the temperature using 2 Bosch coils and cost less than upgrading to the Crane PS91 or PS92 coil.

Wires
Use 9mm Eagle spiral core wires. However, other 9mm spiral core wires such as Crane, MSD, etc may be used with the DirectHits spark amplifiers. DO NOT use silicone wires, they use a carbon core instead of wire that cracks easily with heat and handling which causes misfire with the spark amplifiers.

Impulse Engine Technology P/L

PO Box 986 Randwick NSW 2031 Australia
Ph: (02) 9662 1577
Fax: (02) 9662 1477

International: Ph: +(612) 9662 1577
Fax: +(612) 9662 1477

Email: kits@impulsengine.com


Inventor of Negative Pressure Supercharging

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