Early vs. late ignition boxes

[JPaganel]

Since I have an 86, I have the TCI with the vacuum retard. If I understand correctly, late models don't have that.

Are the TCI boxes interchangeable? Most bikes of the era don't have the vacuum port, so I assume they just get RPM from the pickup coils.

[Pat Conlon]

There is no retard function, only an advance that happens at closed throttle, explained here:
http://www.fjowners.com/index.php?topic=11690.0

All USA bikes have this function as part of the EPA smog requirements.
The early TCI ignitions had them built into the ignition box the later DCI ignitions had the vacuum switch located outboard, under the right side of the fairing with the switch wires going back to the ignition box.

I recall someone posted that the JDM and EU versions of the FJ did not have this advance feature, perhaps someone can chime in here....i do know that all USA bikes have the advance.

No, the early TCI (Transistor Controlled Ignition) and later DCI (Digital Controlled Ignition) are not interchangeable, they use different pickup and rotor assemblies.

Hope this helps... Pat

[movenon]

There is no retard function, only a advance happening at closed throttle, explained here:
http://www.fjowners.com/index.php?topic=11690.0

All USA bikes have this function as part of the EPA smog requirements.
The early TCI ignitions had them built into the ignition box the later DCI ignitions had the vacuum switch located outboard, under the right side of the fairing with the switch wires going back to the ignition box.

I recall someone posted that the JDM and EU versions of the FJ did not have this advance feature, perhaps someone can chime in here....i do know that all USA bikes have the advance.

No, the early TCI (Transistor Controlled Ignition) and later DCI (Digital Controlled Ignition) are not interchangeable, they use different pickup and rotor assemblies.

Hope this helps... Pat

In addition the DCI has the fuel pump relay control circuit.  The pin out location or functions from the DCI might also be different?  That's beyond my level of knowledge.   

Some questions here but if you mounted a 89-93 pickup plate, pickup and the small wiring harness (you can make this harness), installed the the 87-93 DCI if that wouldn't work ? Unknown is the pin layout comparison between the TCI and the DCI.  The programmed advance curve is probably pretty close?  Then you could also add a fuel pump and relay at some point.  Just throwing stuff on the wall 
George

[Arnie]

Pat said, "I recall someone posted that the JDM and EU versions of the FJ did not have this advance feature, perhaps someone can chime in here...."

The only advance mechanism on my '91B model FJ is wholly contained within the ignition unit.
There are NO vacuum tubes (other than the normally capped sync ports) coming from the manifolds.

[Pat Conlon]

Thanks Arnie! 

[JPaganel]

The reason for the question is that I was considering upgrading the ignition to an Ignitech unit. They don't have a vacuum advance, and being Czech, they are unfamiliar with US bikes.