Re: TFI and HEI what\'s the difference?
Gee, there seems to be a question of Semantics here.
You said: """"That snapper-head chaps my ass...""""
Thought it was directed at me. Whoever it was directed to, it's not nice. This place is for information sharing, we all can learn something here. Pirate is the place to insult folks.
It hit me - irritated me, my response wasn't nice either. I applogize.
Now for the meat of it - The semantics - what was written vs what was meant.
You said: """""""""""Takes my upgrades, trys adding a HEI module, screwed that, and declares himself the last word in the subject."""""
Just now you said:
""""I said I BROUGHT the Motorcraft Upgrade to the BBS, and the Jeeping community in general.
I NEVER CLAIMED I INVENTED, DESIGNED or INSTALLED THE IGNITION SYSTEMS IN JEEPS...""""
I guess the words got mixed in the ether?
I HAVE installed several big cap upgrades, along with several HEI modules in the last few months. And a few MSD's. I've also done several years ago, but I'm not sure I ever did a Jeep then.
Yes, DIS is short for "Distributorless Ignition System," or sometimes it's short for "Direct Ignition System."
Yes, the advantage of having much more time to charge, then discharge the coils is obvious. Aftermarket DIS systems have been around a long long time, OEM recently discovered it.
F1 - Formula 1 cars. Not OEM prototypes. OEM's learn from it, often even offer engineering, equipment or parts.
What we had in our shop was usually partially built systems, we'd design the chassis around the equipment to the customer's requirments. Sometimes we'd be working on the finished car too. Gotta admit, that was not a profitable business!
As far as your "dual" ignition - did a bit of experimenting yesterday.
Fabbed a Y coil wire - to be able to feed from 2 different coils. One a Ford coil, the other the HEI remote E coil. Customer's YJ, stock Ford module/pick-up coil. He gave me permission to experiment, he was really in to get a little welding done - cracks in the frame etc..
Attaching the the Y coil wire to both coils did not seem to make any difference - but the HEI coil was still not connected other than the Y coil wire.
Connected the + side of the HEI coil to +12 volts. Oops, Duraspark output voltage increased! Had the scope on it monitoring available voltage.
Hmm, realized on BOTH coils, the bottom end of the secondary winding is tied to the + side of the primary! That's so it can multiply the output like a flyback or auto transformer.
The act of putting the 12 volts on the HEI fed that full 12 volts to the Duraspark coil!
So obviously the power sources to the + side of the coils - whther resistor or not - need to be switched off on the unused one - not just the power to the module, but to the + side of the primary. Need 2 a pole switch to do that.
Disconnected the 12 volts to the HEI coil. Back to normal.
Now I hooked up the HEI module to the (-) side of the coil. Module was grounded properly, although with a clip lead.
Available voltage (still running on the DS) dropped way down! But I still hadn't powered the HEI module yet! It's supposedly would be turned off without main power.
I suppose the + getting to the + side of the coil through the Y coil wire was enough to turn on the HEI Module through the (-) side, at least partially. That then was grounding the secondary through the primary - or something. HEI module still had no power directly to it! Ran OK at idle, but fell on it's face trying to accelerate.
OK, another pole on the switch, one to cut off power to each coil +, one to cut off power to the modules and one to disconnect the (-) coil leads. 3 poles needed now.
OK, works now, both systems. I can switch between them with no ill effects. To this point I was manually swapping over the input from the PU wires. Still not a true "comparison" while driving.
Now for the inputs. Tried connecting both wires to both modules. Found that BOTH wires need to be disconnected from the module not in use. Disconnecting just one wire wasn't enough! Else the PU coil output was severely reduced, what was left was just barely able to trigger either module! Too much load on the PU to drive the one in use properly.
That necessitates even 2 more poles on that switch! Giving 5! That's an unusual switch!
Double throw switch:
1. One double throw pole to switch module main power on and off to each module one at a time. Disables the module not in use.
2. Another double pole to connect/disconnect the (+) primary side of each coil to prevent backfeeding.
3. A third double throw pole to connect/disconnect the (-) side of each coil, one at a time to prevent loading by the unused coil.
4,5. 2 contacts more to switch BOTH PU coil wires to the module to be used.
Obviously I didn't have a switch that complicated. Radio Shack didn't either.
Switching the high tension coil wire instead of using the Y would would make it simple, but a switch to swich over that much voltage? $$$$$
Wow, getting complicated!
Each ignition system worked fine when independant, but if any of the above was still connected, it barely got out of it's own way!
Test equipment used to "see" what the voltages were doing: One old worn out Sun ignition analyzer (a pos.)
One lab scope.
Several test drives, some not even out of the driveway!
Maybe this should give you some insight on why neither of yours works right.
He He - I learned something -- just not sure what yet!