Bill's 2.8 -4 Twin Plug Thread, 48x38 twin plug conversion Options

[Bills914-4]

Here's a few pic's of my planned conversion to twin plug with a Pauter cam (IMG:style_emoticons/default/smile.gif) , &
either MSII or MegaJolt with edis4 x 2 for ignition, Bill D.

[jimkelly]

http://thedubshop.net/

would dual plug be worth any extra HP on an otherwise stock engine?

does emw have a website?

carry on : )

[rick 918-S]

http://thedubshop.net/

would dual plug be worth any extra HP on an otherwise stock engine?

does emw have a website?

carry on : )

Jake posted in another twin plug thread that the twin plug worked best on large displacement engines. I would assume that would have to with the added volume of charge and the increased chamber area for the charge to expand. But I'm no expert.

[Jake Raby]

http://thedubshop.net/

would dual plug be worth any extra HP on an otherwise stock engine?

does emw have a website?

carry on : )

Jake posted in another twin plug thread that the twin plug worked best on large displacement engines. I would assume that would have to with the added volume of charge and the increased chamber area for the charge to expand. But I'm no expert.

Correction: Large BORE engines, even a 2.0 thats a short stroke, large bore could benefit greatly from twin plugs, just like the same bore on a 3.1L beast :-) Thats because the dwell time for flame propagation matters so much more with large bores. Having two plugs on opposite sides of the chamber allow for two flame fronts that meet in the center of the chamber rather than a single flame front that has to burn across the chamber more slowly.

I find that most large bore single plug engines require 32-34* BTDC timing to optimize, while the same heads and cam when used on a smaller (96mm) bore will optimize at 26-28* BTDC. This screams efficiency because the same (105-107mm) bore size with twin plugs will optimize with 22-24*BTDC timing as a twin plug engine.

Any engine that we build thats over a 102mm bore gets twin plugs, as standard. And a roller camshaft :-)

When it gets interesting is adding more dwell time to one plug more than the other and then firing one plug before the other, or splitting the timing up between the two plugs by a couple of degrees. It will make your head spin, but the torque scale on the dyno will twist even further. Thats how I built a 249HP, 2.8L engine that still averaged 35 MPG running at 80 MPH.

This post has been edited by Jake Raby: Nov 27 2013, 09:20 AM