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View Full Version : "twin maggies" - Translation: 2 spark plugs per cylinder


MrShadow
20-03-2003, 03:22 AM
[color=#000000:post_uid9]Would having two spark plugs per cylinder make much difference in a car engine? *I know in an aviation piston engine, you get considerably more power running two sparks per cylinder (then again, we red line at around 2,500 RPM). *It's not like it would weigh much (if you can get it into an aircraft, where every gram counts, I'm sure you could get one into a car no probs). *I'm just wondering, cause it would be easy for manufacturers to to do. *I know of only one [b:post_uid9]production[/b:post_uid9] car that uses this (a recent model Alfa). *Any ideas?[/color:post_uid9]

Cosmo Dude
20-03-2003, 03:59 AM
[color=#000000:post_uid0]The Nissan Z series engine had twin spark (also some CAs).
They were in Pintaras, Vanettes and utes with four cylender engines, also the Jap Bluebird Z-18 Turbo. The engine output was increased slightly and emisions cleaned up a bit more but nothing to write home about. ???
All of these engines were SOHC as it would be more difficult to put in twin-cams.

Rod[/color:post_uid0]

ABC
20-03-2003, 10:17 PM
[color=#000000:post_uid0]yeah, I would have thought that having an extra spark would increase the efficiency by having a more complete burn but wouldn't have thought that the power increase would be all that much.[/color:post_uid0]

MrShadow
21-03-2003, 07:06 AM
[color=#000000:post_uid0]In the aircraft I fly, you generally get an extra 50 RPM bu running both, but that is a fair amount of power difference, you'd definatley notice it if one failed on take-off...[/color:post_uid0]

BigMal
21-03-2003, 07:38 AM
[color=#000000:post_uid1]Similar effect to running the multi-tip spark plugs with
4 contacts to spread out the spark. Problem was that
unless you run individual coils to each cylinder and have
a large alternator etc all it did was quarter the spark
of that made by a normal spark plug so the gain through
better flame front was minimal performance wise.
Think same applies here that unless all the electronics
are beefed up then you will be wasting your time and money.

Regards

Mal[/color:post_uid1]

MrShadow
22-03-2003, 12:03 AM
[color=#000000:post_uid0]Oh, yeah, of course. I mean, we run two independant magnetos, and I'd expect you'd do soemthing similar (or run a VERY big alternator). Although, we run two mainly for safety reasons, not perfomance.[/color:post_uid0]

Cosmo Dude
22-03-2003, 04:22 AM
[color=#000000:post_uid0]The first step in creating a stronger spark would be to pay a lot of attention to earthing the engine and supplying power to the coil/spark-pack/dizzy.
The less resistance and more copper in the circuit the better the spark.

Rod[/color:post_uid0]