Twin Spark, who's done it? how? |
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Twin Spark, who's done it? how? |
brer |
Jan 17 2007, 10:13 PM
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#101
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Advanced Member Group: Members Posts: 2,555 Joined: 10-March 05 From: san diego Member No.: 3,736 Region Association: None |
I have seen the twin spark dizzies. Straight forward.
Then there are the crank fire twin pack setups. ok. what else can be used? Piggyback systems? (picture is for entertainment purposes only. this is not my motor) Attached image(s) |
DNHunt |
Jan 19 2007, 07:36 AM
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#102
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914 Wizard? No way. I got too much to learn. Group: Members Posts: 4,099 Joined: 21-April 03 From: Gig Harbor, WA Member No.: 598 |
Meanwhile. I'd want independent spark control for the second set of plugs. Megasquirt? Not at present without fudging it up. Read 2 separate ECUs sharing the same crank sensor and cam sensor. Currently, there is a max of 4 ignition outputs which could do a 4 cylinder COP or cylinder twin plug (Wasted spark) per board. Advance is only 1 table per ECU so the only way to delay firing of the 2nd plug is to use a second ECU. Too much fudging and room for error in my mind. There is another board in testing that will expand the ignition outputs to 8. I don't know if it will allow separate control of each output. Even if it does I can't imagine tuning it. As a point of interest, tuning ignition on the street is really hard. I can't say I can do it. To tell the truth, you can collect so much data it becomes more than you can use. I suspect to do a really good job one would need exhaust gas temps from each cylinder and head temps from each cylinder along with air fuel ratio. That would mean that for every sampling and in MS you can sample each rotation you would be looking at those 9 columns and MAP, RPM, throttle opening, pulse width and advance. The thought of all of those numbers makes my head spin. Course you could only sample every 50th rotation or some other number but, then you have to wonder if you'll miss something. Fortunately I have an ignition map Jake supplied me that I have changed very little and I know it is safe. Advance comes in early and falls off at higher RPMs. I would have never found that last part without Jake's help and most tables I have seen have advance steady after it reaches max. With Jake's permission I'll share that table with the usual warnings (If you melt it it's your lump). Sorry but, such is life when you're trying off the wall stuff. Dave |
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