There have been a couple dual plug head companies over the years. There was one in Melbourne FL I tried to get an interview with in the 90's.
The trick with dual plugged heads is that the second plug needs to fire about 5 degrees later than the first one to get the scavenger effect on the un-burned fuel, and that is no simple trick.A lot of that dual-plugging went on back in the day with not only Shovels but Iron XL's as well.
Looked cool, and was bragged about while in the taverns, but that was about where the fable ended.
Never saw any additional power on the dyno with a street engine from that work being performed/money spent.
For a fact, the Moco did not offer any dual-plugged Shovel engines.
Scott
In todays day and age one would think this would be stock?Dual plug setups were pretty common.
The trick setup was 4 valve heads.
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Still available. Never even thought of them till this thread.Welcome To Arao Engineering:hello
In todays day and age one would think this would be stock?
I'd take that on my bike. It feels like it could uproot trees at low rpm's, but falls on it's face at about 4000 rpm.One thing you need to keep in mind with 4v heads vs 2v heads is that you trade off some low end torque for upper rpm HP.