Spark Placement

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demilus
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Mon Sep 25, 2006 7:19 pm

I'm working on a combustion right now and am using a BBQ ignitor for the spark. The chamber is about 16" x 4" so it is decently sized. Where should the spark be placed (front, back, middle, etc.)? Does where it is placed affect the performance? Thanks
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mark.f
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Mon Sep 25, 2006 7:46 pm

It'll work great (best) at the back of the chamber.

Dual sparks work well also, if you want to try that.
Blackspire
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Mon Sep 25, 2006 11:18 pm

markfh11q wrote:It'll work great (best) at the back of the chamber.

Dual sparks work well also, if you want to try that.
How would you recommend doing that with bbq sparkers?
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mark.f
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Tue Sep 26, 2006 5:37 am

Wire two spark gaps in a series. Just make sure they're not too far apart, (a gap of about 1/16" - 1/8", or they won't spark.
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FiveseveN
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Tue Sep 26, 2006 7:12 am

I do believe it has been demonstrated that a spark in the center is the best option with single sparks. If you want dual sparks, put one at 1/3 and the other at 2/3. I don't think a piezo BBQ sparker can handle dual sparks, though.
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boilingleadbath
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Tue Sep 26, 2006 4:35 pm

.23cal, that would be true if the chamber was compleatly closed.
However, it's not - so you get some advantage from putting the spark closer to the rear.
(more air flow towards the barrel, causing more turbulence, which increases burning rate [from the gexcon handbook of gas explosions])
brumby
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Fri Oct 06, 2006 11:49 pm

Ok so ill place my spark about 1/3 at the back
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