Multiple Spark systems, Mallory, Permatune with DJET??? |
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Multiple Spark systems, Mallory, Permatune with DJET??? |
r_towle |
May 5 2008, 04:55 PM
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#1
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Custom Member Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
So, as the title says.
Do these multi spark systems work with DJet? If so, are there improvements? I am not looking for more power, but more MPG...more efficient burn. Rich |
ericread |
May 7 2008, 01:20 AM
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#2
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The Viper Blue 914 Group: Members Posts: 2,177 Joined: 7-December 07 From: Irvine, CA (The OC) Member No.: 8,432 Region Association: Southern California |
I know that everyone seems to be tiring of this thread, but just one more question...
Please explain to me the value of the multiple spark system. My understanding of ignition is that the timing of the spark is very important to the correct operating of the engine. Too early and you lose compression quality of the piston downstroke, too late and you lose the the quality of the fuel/air mixture (or some such stuff - I have no doubt someone will correct this with a better, more correct description). So with a multiple spark, aren't you risking late ignition of some of the gasses. And wouldn't the value of catching these un-ignited gasses only be valid in the case where the original spark is not firing correctly? And do you really want a late ignition to occur? It just seems to me that if your spark plug is providing a correctly timed spark, there would be little to be gained by the multiple spark system (IMG:style_emoticons/default/confused24.gif) Sorry for all the questions, but thanks in advance for your reply. |
r_towle |
May 7 2008, 12:42 PM
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#3
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Custom Member Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
I know that everyone seems to be tiring of this thread, but just one more question... Please explain to me the value of the multiple spark system. My understanding of ignition is that the timing of the spark is very important to the correct operating of the engine. Too early and you lose compression quality of the piston downstroke, too late and you lose the the quality of the fuel/air mixture (or some such stuff - I have no doubt someone will correct this with a better, more correct description). So with a multiple spark, aren't you risking late ignition of some of the gasses. And wouldn't the value of catching these un-ignited gasses only be valid in the case where the original spark is not firing correctly? And do you really want a late ignition to occur? It just seems to me that if your spark plug is providing a correctly timed spark, there would be little to be gained by the multiple spark system (IMG:style_emoticons/default/confused24.gif) Sorry for all the questions, but thanks in advance for your reply. There is alot of unburnt fuel in our aircooled motors that gets wasted. Its a factor of the head design and the location of the spark plug and the chamber design, along with the piston design. This type of system shoots off multiple sparks that will ignite more of the fuel and create a more efficient burn on each stroke. The spark is also hotter if properly installed with new wires. Because the spark is hotter, more voltage is going to the plug. You can run colder plugs and you need more of a gap...well you can use more of a gap. Its a bigger spark. The idea behind this is to burn more of the fuel in the chamber instead of pushing it out the exhaust into the atmosphere. The results are more power per stroke. Rich |
ericread |
May 7 2008, 02:50 PM
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#4
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The Viper Blue 914 Group: Members Posts: 2,177 Joined: 7-December 07 From: Irvine, CA (The OC) Member No.: 8,432 Region Association: Southern California |
There is alot of unburnt fuel in our aircooled motors that gets wasted. Its a factor of the head design and the location of the spark plug and the chamber design, along with the piston design. This type of system shoots off multiple sparks that will ignite more of the fuel and create a more efficient burn on each stroke. The spark is also hotter if properly installed with new wires. Because the spark is hotter, more voltage is going to the plug. You can run colder plugs and you need more of a gap...well you can use more of a gap. Its a bigger spark. The idea behind this is to burn more of the fuel in the chamber instead of pushing it out the exhaust into the atmosphere. The results are more power per stroke. Rich Rich; Thanks, this is starting to make sense. However, I still do not understand a hot spark versus a cooler spark. My understanding is that our 914s should run a cooler spark. If we run a hotter spark, do we compromise the fuel burn in the cylinder? And does a hotter spark mean a shorter spark period? Again, my thanks. |
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