Performed a DIS test today to test a theory.

[Anlushac11]

Put new plugs and wires in my 91 LX convertible today and got to thinking.

My friend and I got the passenger side done and I decided before doing other side to disconnect all the plug wires off drivers side and see if car would start.

It did.

I then drove car around the block and no problem. I drove it home about 12 miles from friends house just now with no problems.

Sooo... The reason for this is my friend has a 87 TC engine that is mine for the taking if I decide to keep the 4cyl.

If I dont do my I6 swap I was theorizing rebuilding bottom end of 91 DIS motor to turbo specs and dropping on the 87 TC head, intake, and exhaust. Since I have been able to run the engine on one coil pack that means it should be able to run on a 4 plug head.

BTW small humour moment. Kid at Advance Auto Parts brought me out 4 spark plugs and I asked for the other 4 and when I explained that my car was a 4cyl with 8 plugs he thought I was lying to him. The kids co-workers were rolling on floor.

Would be interesting to have a DIS on a turbo motor, especially now that there are kits like Megajolt that I can build to custom program and tune a DIS with.

 

[65ShelbyClone]

You know, I haven't been able to pin anyone down on exactly how the secondary plugs work in the DIS 2.3s. I would like to know if they fire simultaneously or in a "trailing spark" fashion.

 

[stykthyn]

and you didnt notice a complete lack of "oomph" in your car?? when my DIS crapped out, half the plugs stopped firing and the car was an even bigger turd than it's normal self.

 

[Anlushac11]

It was my understanding that the two spark plugs per cylinder was a attempt to reduce emissions by trying to promote more complete burning of the air fuel mixture in IIRC is a open chamber low swirl head.

My 91 has one coil running passenger side plugs and the other coil runs drivers aside plugs. All I did was remove the plug wires from drivers side coil.

Car runs smooth when cold but runs rough and misses out when warmed up.

IMHO the coil crapping out should not have caused the car to lose much if any power unless the computer kicked into limp home mode when it read the bad coil. That is possible but at this point the car runs so bad this setup is actually a slight improvement.

 

[ethangsmith]

When I was at college in Williamsport, PA there was a guy that had a Pinto with a 2.3 Turbo and ran the 8 plug head with DIS. He also got rid of the VAF in favor of a MAF sensor. So, it is possible to do.

 

[samickguy15]

There is a way to wire the coils so that you can remove the second coil pack. I recall seeing that info over on Turboford, but I can't remember what wire went where...

 

[Touring23]

It was my understanding that the two spark plugs per cylinder was a attempt to reduce emissions by trying to promote more complete burning of the air fuel mixture in IIRC is a open chamber low swirl head.

My 91 has one coil running passenger side plugs and the other coil runs drivers aside plugs. All I did was remove the plug wires from drivers side coil.

Car runs smooth when cold but runs rough and misses out when warmed up.

IMHO the coil crapping out should not have caused the car to lose much if any power unless the computer kicked into limp home mode when it read the bad coil. That is possible but at this point the car runs so bad this setup is actually a slight improvement.

If you must, disconnect the coil connector rather than the plug wires; disconnecting the plug wires puts a lot of stress on the secondary windings of the coil. However, that will trigger a CEL. If you want to disable the dual-plug mode, look at the DPI signal between the ICM & PCM.

But this is all going the wrong way. My '93 lost 8-10% on the dyno when I unplugged a coil.

Now here's a question for everyone: Why does this Ferrari 275 GTB Daytona have dual plugs? How about this one?
Here are a few more:
http://www.floheadworks.com/articles/detonation.htm
http://www.land-and-sea.com/marine/heads/heads.htm
http://www.rennsportsystems.com/~porsche/2a.html

*edit* Oh, BTW, anyone up for factory dual-plug turbos?
Toyota: http://www.toycrazy.net/tech/3tgte.htm
Nissan: http://www.geocities.com/billdacat8/Z18etinfo.html
I have more, but the point should be clear by now.

65ShelbyClone, I believe the dual-plug Mercedes, Hemi's, and Honda's i-DSL use stagger-fire timing, but these old Fords aren't that sophisticated. There's only one PIP signal and no stagger signal. For more info, check out the waveforms in the Emissions Manual if you get a chance.

IMHO, the dual plug feature is one of the few positive things about the 2300.

 

[Touring23]

Gee, it got awfully quiet in here.

Anlushac, you might find this discussion at RPS useful.