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RClewett RClewett is offline
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Join Date: Apr 2010
Location: California
Posts: 15
Jimmcc,

The accuracy of a high resolution ignition system come from the number of points on the crank trigger. Most of the aftermarket systems available don't have the processing power for the high massive amounts of data generated by the 60 minus 2 input.

The high resolution angle based sensor arrangement typically uses a 60 minus 2 trigger wheel on the crank and a magnetic speed sensor. On the 964, 993 and later engines we use the 60 minus 2 on the flywheel from Porsche. Most of the new cars on the market use a high resolution system. The Electromotive ignition is true high resolution angle based system which updates crank position every 6 degrees of crank rotation. This data is processed & refined and the coil is fired at the precise crank angle. This type of system eliminates what is known as spark lag.

Low resolution or time based systems might use a 3 or 6 tooth (120 or 60 degree)trigger wheel or bedded magnets and a hall sensor for inputs. That data is then used calculate the time when the spark event should take place. This type of system has spark lag or latency which will affect timing accuracy during RPM changes, acceleration and deceleration.

I hope this answers your question.

Richard
Old 04-28-2010, 12:57 AM
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