Tfidfis
03-26-12, 09:01 PM
#151
Its pretty simple. I just used a standard 30 amp relay. I wired positive from the
battery to the 30 terminal and the hot side of the igniters and coils were connected
to 87. I then wired the BW ignition wire to 85 and put 86 to ground.
I think thats how I did it
Anyway, I verified that when the ignition was on that I saw +12 volts
on 87 and when it was off I made sure to see 0 volts as well. Its just a switch
after all. Theres lots of info on the web for hooking up accessories with a relays.
battery to the 30 terminal and the hot side of the igniters and coils were connected
to 87. I then wired the BW ignition wire to 85 and put 86 to ground.
I think thats how I did it
Anyway, I verified that when the ignition was on that I saw +12 volts
on 87 and when it was off I made sure to see 0 volts as well. Its just a switch
after all. Theres lots of info on the web for hooking up accessories with a relays.
03-27-12, 06:34 AM
#152
Waffles - hmmm good
Thread Starter
iTrader: (1)
Yeah, if you wouldn't mind putting together an updated wiring diagram for us I would be VERY grateful. I've long had this on my to do list as I work towards completing the restoration of Gus. I am interested in the raspier exhaust note you mentioned, and particularly the smoother revving. I used a 2GCDFIS setup in the past, but it felt kind of choppy to me, or hesitant almost. Like it didn't really want to rev up, but did it because it didn't want to disappoint me. 
I'm definitely going to try this TFIDFIS setup. So, if you could throw together an updated wiring diagram in paint and post it that would be awesome.
I'm definitely going to try this TFIDFIS setup. So, if you could throw together an updated wiring diagram in paint and post it that would be awesome.info for how its done.
03-28-12, 11:49 AM
#154
The following 2 users liked this post by t_g_farrell:
midnight mechanic (07-16-21),
rotaryengineering (03-01-24)
03-29-12, 07:08 AM
#156
Waffles - hmmm good
Thread Starter
iTrader: (1)
Your very welcome. Its great when folks give feedback into threads like this. Its
one of the reasons for doing it I think.
How do I collect those millions anyway
I only use the leading and only have 2 HEIs and the 2 coils now. I don't have any
plug wires going to/from the dizzy anymore. If I didn't need/want mech/vac advance
on the dizzy I could just go to a 2G CAS and stick it in the dizzy hole. I wasn't sure of
this until recently when discussing it with some folks I know that have a bit more experience with the 2G CAS operation.
one of the reasons for doing it I think.
How do I collect those millions anyway
I only use the leading and only have 2 HEIs and the 2 coils now. I don't have any
plug wires going to/from the dizzy anymore. If I didn't need/want mech/vac advance
on the dizzy I could just go to a 2G CAS and stick it in the dizzy hole. I wasn't sure of
this until recently when discussing it with some folks I know that have a bit more experience with the 2G CAS operation.
06-12-12, 06:02 PM
#157
Quick question: Do the weather pack style 2000+ 4.3L GM HEI modules work? They are divorced from the distributor and have a nice sealed weather pack connector for the wires.
I don't think GM changed anything else other than changing from the vertical post cap to a horizontal crisscross cap.
I don't think GM changed anything else other than changing from the vertical post cap to a horizontal crisscross cap.
06-13-12, 06:58 AM
#158
Waffles - hmmm good
Thread Starter
iTrader: (1)
I don't know, can you supply a pic or specs?
Is it the one with the yellow dot in this picture from the MS site:
All of these should work. The MS site gives details on the pinouts for each but they
are pretty similiar.
http://www.msextra.com/doc/ms2extra/MS2-Extra_HEI.htm
Is it the one with the yellow dot in this picture from the MS site:
All of these should work. The MS site gives details on the pinouts for each but they
are pretty similiar.
http://www.msextra.com/doc/ms2extra/MS2-Extra_HEI.htm
06-13-12, 10:33 AM
#159
From earlier in the thread. The one on the top left. They come with their own little heat sink. IIRC '95 was actually the year they started it as you could have the old style setup or this new version. I will try to find a schematic.
The yellow dot one you mention is the 8pin and I have a dozen of those laying around from my old v8 projects with the small cap HEI.
06-13-12, 11:54 AM
#161
Waffles - hmmm good
Thread Starter
iTrader: (1)
I'm thinking that control module is a digital version, meaning the input signal to
trigger the spark is at some reference voltage for the waveform like 5 or 12 volts.
The 4, 7, and 8 pin HEI modules will all work with a weak analog waveform as
generated by the mag pickup in the distributor.
So my guess would be that it won't work. I couldn't find any schematics for that
particular ignition control module. A GM part number would help if we want to fully
research it.
trigger the spark is at some reference voltage for the waveform like 5 or 12 volts.
The 4, 7, and 8 pin HEI modules will all work with a weak analog waveform as
generated by the mag pickup in the distributor.
So my guess would be that it won't work. I couldn't find any schematics for that
particular ignition control module. A GM part number would help if we want to fully
research it.
06-13-12, 12:21 PM
#162
That makes complete sense. It looks like a more intelligent device. When I saw the schematic I figured it wasn't a nicer package for the old HEI 4 pin. Trying to make a nice aesthetic setup using your system which is hard to do with the open terminal HEIs.
Here is the Delphi number from Napa's listing. DEM DS10039
Here is the Delphi number from Napa's listing. DEM DS10039
07-03-12, 04:14 PM
#163
This is a really stupid question probably, but how do you know which leading TFI coil to hook to which spark plug? Does it matter? I'm going to be deleting the trailing ignition just like you did, so I would only have two plug wires. One from each coil to each leading spark plug, right? Which coil goes to which plug?
Sorry, I'm an idiot when it comes to electrical stuff.
Thanks,
Jamie
Sorry, I'm an idiot when it comes to electrical stuff.
Thanks,
Jamie
07-03-12, 05:25 PM
#164
Correct me if I am wrong, but it shouldn't matter.
The leading signal from the dizzy gets split to both coils. They both fire at the same time. One starts the combustion cycle, the other is "wasted" as the term is coined and just fires the plug while the rotor is in a position that is unaffected.
Therefore you hook the leading plug wires to the leading coils in any arrangement.
The leading signal from the dizzy gets split to both coils. They both fire at the same time. One starts the combustion cycle, the other is "wasted" as the term is coined and just fires the plug while the rotor is in a position that is unaffected.
Therefore you hook the leading plug wires to the leading coils in any arrangement.
The following users liked this post:
SunRedRX7 (09-17-17)
08-06-12, 03:37 PM
#167
Waffles - hmmm good
Thread Starter
iTrader: (1)
Sweet! Thanks for adding that nice graphic.
For any of you that have done this in the past, post up about how its holding out or what
your experience with it has been. I'd love to hear the stories.
For any of you that have done this in the past, post up about how its holding out or what
your experience with it has been. I'd love to hear the stories.
10-16-12, 11:14 AM
#169
Waffles - hmmm good
Thread Starter
iTrader: (1)
Heres an update, you don't need trailing anymore with this ignition setup!
Let us know how it goes. Anybody done any dyno runs with this yet?
The more anecdotes the better in this thread. We all learn something from them.
Let us know how it goes. Anybody done any dyno runs with this yet?
The more anecdotes the better in this thread. We all learn something from them.
10-16-12, 04:49 PM
#170
Lurking on thread near U
Join Date: Dec 2008
Location: Huntsville, Alabama
Posts: 143
Likes: 0
Received 0 Likes
on
0 Posts
Although I haven't used the tfi coils, I've experimented with the DLIDFIS setup on a few cars and my experience has been that although the trailing spark seems to make little difference in power, I have noticed an improvement in fuel economy when I retain the trailing. Although I'm certainly not an expert in the subject (oh the things I'd do to have access to the data and models mazda has come up with on airflow and flame propagation inside the chamber), I do believe I have an idea why.
The renesis multi side port, for example, gets the majority of its fuel mileage and emissions improvement not from the change in port timing, but rather due to the fact, pure and simple, that the exaust ports are in the side irons. As the rotor spins, fuel seems to concentrate and "puddle" against the trailing apex seal edge. This area of the chamber tends to be much richer than the rest of the chamber, and often leaves quite a bit of unburned fuel to simply get spit out the peripheral exhaust port. We see evidence of this with the common backfires and exhaust temps that generally run much higher than you would normally see on a piston engine. In a renesis msp engine, this partially burned fuel can remain against the edge of the apex seal and be re-cycled to the next combustion phase, instead of simply getting spit out the peripheral exhaust port.
It is my understanding that the main function of the trailing ignition on these cars (and location of the trailing plug) is to help burn as much of this fuel as possible inside the chamber, instead of requiring the catalytic converters to clean it up after the fact. Now I'm not an expert in this subject, and I'm sure some of the folks on here will have a better understanding of this phenomenon, but what I can say is that I've seen a marked difference in fuel economy when I leave off the trailing spark, measured at the same temperature/barometric pressure/tire pressure/vehicle weight, on 100 mile 70mph highway trips using fuel from the same station purchased on the same day. If I recall, my weber carbed streetport 12a managed 21mpg with trailing, 18 without. At the drag strip however, I've seen no meaningful difference in trap speed.
Not to hijack the thread, but perhaps someone on here might be able to shed more light on the topic?
The renesis multi side port, for example, gets the majority of its fuel mileage and emissions improvement not from the change in port timing, but rather due to the fact, pure and simple, that the exaust ports are in the side irons. As the rotor spins, fuel seems to concentrate and "puddle" against the trailing apex seal edge. This area of the chamber tends to be much richer than the rest of the chamber, and often leaves quite a bit of unburned fuel to simply get spit out the peripheral exhaust port. We see evidence of this with the common backfires and exhaust temps that generally run much higher than you would normally see on a piston engine. In a renesis msp engine, this partially burned fuel can remain against the edge of the apex seal and be re-cycled to the next combustion phase, instead of simply getting spit out the peripheral exhaust port.
It is my understanding that the main function of the trailing ignition on these cars (and location of the trailing plug) is to help burn as much of this fuel as possible inside the chamber, instead of requiring the catalytic converters to clean it up after the fact. Now I'm not an expert in this subject, and I'm sure some of the folks on here will have a better understanding of this phenomenon, but what I can say is that I've seen a marked difference in fuel economy when I leave off the trailing spark, measured at the same temperature/barometric pressure/tire pressure/vehicle weight, on 100 mile 70mph highway trips using fuel from the same station purchased on the same day. If I recall, my weber carbed streetport 12a managed 21mpg with trailing, 18 without. At the drag strip however, I've seen no meaningful difference in trap speed.
Not to hijack the thread, but perhaps someone on here might be able to shed more light on the topic?
10-17-12, 02:20 AM
#171
BeenJaminJames, fun tidbit of trivia for you. The RX-8 has single leading sparks per rotor face. However all US-spec FCs and FDs had dual leading sparks per rotor face, as does DLIDFIS and of course t_g_farrell's ford coil version which is the same thing. And other variations like the MSD (if hooked up a certain way ie as direct fire and not through a cap and rotor). Also 2GCDFIS which is somewhat inferior to the others I just mentioned. These all have the normal spark at or around TDC and a second late firing leading spark 180 degrees later.
So what does the single leading spark vs dual leading spark have to do with the RX-8 and why did they drop the second or "late leading" spark? They discovered that the late firing leading spark was igniting the mixture in the trailing edge of the rotor known as the squish zone and filling it with exhaust gasses that weren't vented as effectively from side exhaust ports as they had from peripheral exhaust ports. They needed that area to contain more unburned fuel. So they dropped the late leading spark.
Now since you have a peripheral exhaust port rotary, I'd recommend an ignition upgrade that has a late firing leading spark. Any of the above will do, but I prefer DLIDFIS because I refuse to install any ford part under my hood.
But GM and Bosch are ok.
And if you're into megasquirt, stay away from ford's EDIS system too. Inferior and can't provide late leading nor can it do a trailing split if I recall correctly. There are better ways that let you use stock or upgraded FC and FD coils+ignitors.
Oh and to answer your other concern, I keep trailing. I just move its wires to the leading part of the cap to take advantage of one less gap to jump. But I won't go out of my way like some people do to create a trailing direct fire setup. Or get two MSD boxes - one for each trailing plug like some FC and FD guys who have more dollars than sense. That's madness right there.
So what does the single leading spark vs dual leading spark have to do with the RX-8 and why did they drop the second or "late leading" spark? They discovered that the late firing leading spark was igniting the mixture in the trailing edge of the rotor known as the squish zone and filling it with exhaust gasses that weren't vented as effectively from side exhaust ports as they had from peripheral exhaust ports. They needed that area to contain more unburned fuel. So they dropped the late leading spark.
Now since you have a peripheral exhaust port rotary, I'd recommend an ignition upgrade that has a late firing leading spark. Any of the above will do, but I prefer DLIDFIS because I refuse to install any ford part under my hood.
But GM and Bosch are ok.
And if you're into megasquirt, stay away from ford's EDIS system too. Inferior and can't provide late leading nor can it do a trailing split if I recall correctly. There are better ways that let you use stock or upgraded FC and FD coils+ignitors.
Oh and to answer your other concern, I keep trailing. I just move its wires to the leading part of the cap to take advantage of one less gap to jump. But I won't go out of my way like some people do to create a trailing direct fire setup. Or get two MSD boxes - one for each trailing plug like some FC and FD guys who have more dollars than sense. That's madness right there.
10-18-12, 07:21 AM
#172
Waffles - hmmm good
Thread Starter
iTrader: (1)
Lots of really good info here!
Ok, then use the GM solid state E coil instead. Should work just as well. I just like
the coil not having oil in it. Less chance for mess and failure in my mind.
I'll give the trailing another go later this winter and measure the mpg with and
with out. I have a 50 mile interstate loop less than a mile from my house and the
gas station is right there. Easy to do in an afternoon.
the coil not having oil in it. Less chance for mess and failure in my mind.
Now I'm not an expert in this subject, and I'm sure some of the folks on here will have a better understanding of this phenomenon, but what I can say is that I've seen a marked difference in fuel economy when I leave off the trailing spark, measured at the same temperature/barometric pressure/tire pressure/vehicle weight, on 100 mile 70mph highway trips using fuel from the same station purchased on the same day. If I recall, my weber carbed streetport 12a managed 21mpg with trailing, 18 without. At the drag strip however, I've seen no meaningful difference in trap speed.
Not to hijack the thread, but perhaps someone on here might be able to shed more light on the topic?
Not to hijack the thread, but perhaps someone on here might be able to shed more light on the topic?
with out. I have a 50 mile interstate loop less than a mile from my house and the
gas station is right there. Easy to do in an afternoon.
10-22-12, 12:10 PM
#173
Lurking on thread near U
Join Date: Dec 2008
Location: Huntsville, Alabama
Posts: 143
Likes: 0
Received 0 Likes
on
0 Posts
BeenJaminJames, fun tidbit of trivia for you. The RX-8 has single leading sparks per rotor face...
...So what does the single leading spark vs dual leading spark have to do with the RX-8 and why did they drop the second or "late leading" spark? They discovered that the late firing leading spark was igniting the mixture in the trailing edge of the rotor known as the squish zone and filling it with exhaust gasses that weren't vented as effectively from side exhaust ports as they had from peripheral exhaust ports. They needed that area to contain more unburned fuel. So they dropped the late leading spark.
...So what does the single leading spark vs dual leading spark have to do with the RX-8 and why did they drop the second or "late leading" spark? They discovered that the late firing leading spark was igniting the mixture in the trailing edge of the rotor known as the squish zone and filling it with exhaust gasses that weren't vented as effectively from side exhaust ports as they had from peripheral exhaust ports. They needed that area to contain more unburned fuel. So they dropped the late leading spark.
Hmmm, I rather like EDIS, from what I know about it, which admittedly isn't that much. But yes, I am starting to get into ms, how'd you guess? How do you like to set up ignition with megasquirt? And on a side note, have you ever squirted a 20b?
10-22-12, 01:32 PM
#174
BeenJaminJames, you're welcome. It's not really common knowledge but I make a point to point it out when necessary.
About the MS, my rotary sense was tingling. It does that sometimes. I get an idea that is so subtle I don't even notice at the time - I just type it because it seems appropriate. Only later I find out how accurate it was to the recipient's situation.
Speaking of which, the version of the MS firmware I use on my MegaSquirted 20B allows late leading sparks at the normal 180 degree times, but there are three events, one for each rotor, which are separated by 120 degrees to coincide with the rotor phasing. So from an individual spark plug's perspective, it can't tell whether it's in a 13B or a 20B because it still sparks every 180 degrees. But if you look at all three spark plugs together, there is a spark event every 60 degrees. I wasn't content with a spark event every 120 degrees. I wanted late leading so I doubled it and got a spark every 60. Does that make sense?
About the MS, my rotary sense was tingling. It does that sometimes. I get an idea that is so subtle I don't even notice at the time - I just type it because it seems appropriate. Only later I find out how accurate it was to the recipient's situation.
Speaking of which, the version of the MS firmware I use on my MegaSquirted 20B allows late leading sparks at the normal 180 degree times, but there are three events, one for each rotor, which are separated by 120 degrees to coincide with the rotor phasing. So from an individual spark plug's perspective, it can't tell whether it's in a 13B or a 20B because it still sparks every 180 degrees. But if you look at all three spark plugs together, there is a spark event every 60 degrees. I wasn't content with a spark event every 120 degrees. I wanted late leading so I doubled it and got a spark every 60. Does that make sense?
