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Discussion Starter · #1 ·
If someone was to put dual plug heads on a single plug head engine lets sat a triple engine. What would one have to do for it to fire right? Just change the coils and thats it? And I suppose richen up the fuel mixture also or what?

Thanks,
Joe
 

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simply run more coils, but in all reality there is more to it than that, you would by rights have to make a completely new head, it really wouldnt work very well by just adding a spark plug to the existing head because of the flame travel would be very dominate to one way or the other. you would be getting detonation or lean spots on part of the cylinder while being rich on the other. if you look at the old vintage sleds that had 2 plugs they both came to the center at an angle. so there flame kernal still started at the center of the head.
 

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Discussion Starter · #3 ·
Thanks for the info, its greatly appreciated. I have an old head thats a dual plug and was going to make a new head to work the same way. What are the PROS and CONS of this?

thanks
 

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first running another set of coils parrallel to the ones you have, and then getting the plug choice dialed in. 2 plugs of the same heat that is currently running 1 plug, you might have to retard the timing or run cooler plugs? the flame kernal with 2 plugs might be to big and create a detonation problem. on the 1000 twin engines they use 2 plugs becuse the bore is so big, with the big bore they have to keep the rpms down to the low 7000 rpm area just to make the engine run good, it takes so much time to fill the bore and for the flame to travel that at any higher rpm and the sled looses power. on a small bore engine 2 plugs might be over kill and create more problems than power.
 

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As an alternative to retarding the timing you could use higher octane fuel, but you might end up using racing gas to get a slow enough flamefront.

Or were you planning on running this on your alcohol motor?
 

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Discussion Starter · #7 ·
Yes I was thinking of doing this on my alcohol engine. But then again I was thinking of putting this on a 650 engine with SLP 707 or 732 big bore kit that I have. I am throwing this idea around for a different drag sled than my alcohol drag sled. Looks like I am gonna have me a fun little project here. The heads are already made up and ready to go for this project. Just trying to finalize on what to do with the engine. Looks like I will start with colder plugs and at least a 92 octane fuel and maybe a octane booster. What do you guys think?

Ugly_old_Poo_kid--------------shoot me an email. my email is getting full of people on ECU's!!!! Haven't talked in awhile. Are you still interested in a partnership?
 
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