Smart plugs? Anybody tried this?

[88HF]

The 02 Si has direct ignition. There is no distributor.

[diamondlarry]

My '07 Prius has coil-on-plug ignition with iridium plugs.

[88HF]

what is the change interval? My dad said in his Si its 100,000

[JanGeo]

Originally Posted by bobski

Yeah, but then you need something to interpret the electrical pulses generated by the magnet and pickup assemblies and use that information to direct the ECU ignition signal to the proper coil.

nope - the magnet on the rotor triggers the sensor for the proper coil just like it used to direct the high voltage coil output and you can gate it with the points cam signal for more accurate timing. you just don't run the high voltage through the rotor to the cap - the rotor does the cylinder selection.

[retrorocket]

Interesting, but I assume it fires both plugs for a given cylinder simultaneously? I have a hard time thinking of a way, short of what amounts to two separate distributors, to isolate the cap contacts from each other enough to allow the plugs to be fired individually in rapid succession.

My Buddies old RX-3 had two distributors and they were timed differently.

I think having to set the timing twice on the same engine is cool!

retrorocket

[GasSavers_bobski]

Ah, yeah... Rotaries commonly use two spark plugs because the combustion chamber is so long. It takes too long for the flame front to propegate down the length of the chamber, so they added a second plug to speed things along. Without it, peak combustion pressure isn't reached quickly enough to take full mechanical advantage of the power... Stroke? Undulation? Whatever you call that phase of rotation.

[Raccoonjoe]

Originally Posted by ZugyNA

I have an '86 2.4L Nissan I4 truck engine with 8 plugs that are fired from a distributor. 2 coils and a lot of wires.

There was a series of 4 cyl Ford Rangers with 2 plugs per cylinder, as well. I also believe that those had distributors, as opposed to coil packs. Sometime in the early-mid 90's, IIRC

[vt420]

yeah.. there were twinspark 2.3s in rangers
alfa had a twinspark engine (non-US)
the new hemi is twinspark (for sure in trucks, I haven't looked in a car)
IIRC jag had a system that fired the same plug twice. two coils, a very strange looking cap and rotor with offset contacts, but only a single plug lead and one plug per cyl
rotories are twinspark as was already mentioned
nissan did it too
it was the in thing for a while, and then disapeared and seems to be making a comeback with DIS, because it's so much simpler to do with dis than with a dizzy

Jeff