Mailing List flyrotary@lancaironline.net Message #29485
From: Ed Anderson <eanderson@carolina.rr.com>
Subject: Fw: 100 vs 600 vs 400 vs 12.5 sparks/second : LS1 Coil Failures
Date: Wed, 18 Jan 2006 17:58:26 -0500
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
 
----- Original Message -----
Sent: Wednesday, January 18, 2006 4:55 PM
Subject: 100 vs 600 vs 400 vs 12.5 sparks/second : LS1 Coil Failures

True, but remember we have two rotors each having two spark plugs (both of which fire) and the trailing coils throw one spark away (waste spark) but still is a coil firing.
 
The rotors are turning 2000 rpm (6000 rpm shaft / 3 ), each rotor fires 3 times for each rotor revolution (three faces per rotor).  2000/60 = 33.33 revs/sec for the rotors.
 
There are 2 rotor with 3 faces each or 6 firing faces per revolution or 33.33*6 = 200 ignition evens per second.  But each rotor has 2 spark plugs both of which fire for each ignition event,  so we have 33.33 * 6 * 2 = 400 sparks second. 
 
 But, each sparkplug is serviced by a separate ignition module so 400/2 =  200 sparks/second per ignition module - still up there compared to a reciprocating engine.
 
Now at Tracy's 7500 rpm {:>), we have 7500/3 = 2500 rotor rpm or 2500/60 = 41.66 revs/second.  From which we  have 41.66*6*2 = 500 sparks per second.  Now since there is a LS1 coil for each plug we can divide load by 4 and 500/4 = 125 sparks second. 
 
 so If my logic and math are correct, Tracy is actually driving the coils less that the Mazda stock coils - but still way above Mark's truck at 12.5 sparks/second.  In fact about 10 times more than Mark's truck with engine turning 1500 rpm.
 
FWIW
Ed
 
----- Original Message -----
Sent: Wednesday, January 18, 2006 11:47 AM
Subject: [FlyRotary] Re: LS1 Coil Failures

Each rotor fires once/revolution of the eccentric shaft.  Cruising along at 6000rpm, that's 600 sparks/second/coil. 

 
Hi Mark,
 
Is this the new math I always heard about :-) 
 
6000 rpm / 60 seconds = 100 sparks per second
 
Cheers,
Rusty (everyone's a critic <g>)
 

 
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