Ok where do these msd wires go
06-29-04, 04:24 PM
#26
Originally posted by Jeff20B
Not at the same time of course. You'd need two MSDs, but trailing isn't necessary to upgrade since it adds so little to engine power no matter what you do. It also become nearly redundant with direct fire on leading because the extra leading spark (180 degrees after it normally fires) ends up doing trailing's job by igniting the trailing edge of the AF mixture (squish area) quite well. You can tell easily if you have an aftermarket exhaust; it's less smelly.
Not at the same time of course. You'd need two MSDs, but trailing isn't necessary to upgrade since it adds so little to engine power no matter what you do. It also become nearly redundant with direct fire on leading because the extra leading spark (180 degrees after it normally fires) ends up doing trailing's job by igniting the trailing edge of the AF mixture (squish area) quite well. You can tell easily if you have an aftermarket exhaust; it's less smelly.
I havent tried leading only. my old set up was the white wire on both trailing and leading igniters. then I switched to YAW style set up...(from the old mazspeed). I cant tell which is better.
06-29-04, 04:32 PM
#27
Two MSDs both hooked to the ignitors, both through the cap? Then when you hooked it up as per Mazdaspeed instructions, did you use two blaster coils?
In my opinion, a dual output (DIS) coil is better to use because it more closely matches the MSD's output. It's better to not split the MSD's output if at all possible, otherwise you'll get a reduction in available amps to the coils. The MSD has limits. The DIS coil has a single primary coil instead of the two primaries of dual coils. My testing of an FC leading coil showed that even if one plug is fouled or has higher resistance than the other, both will still spark. When I learned this, I was all for the FC leading coil and my unused 6AL going onto my next rotary project.
In my opinion, a dual output (DIS) coil is better to use because it more closely matches the MSD's output. It's better to not split the MSD's output if at all possible, otherwise you'll get a reduction in available amps to the coils. The MSD has limits. The DIS coil has a single primary coil instead of the two primaries of dual coils. My testing of an FC leading coil showed that even if one plug is fouled or has higher resistance than the other, both will still spark. When I learned this, I was all for the FC leading coil and my unused 6AL going onto my next rotary project.
06-29-04, 04:41 PM
#28
sorry about the confusion. its hard to work and post ***** at the same time. 
My first MSD ignition was set up using one MSD 6AL. The white wire was bridge and connected to both igniters.
Then I switched to YAW style direct fire system.
Now that you got me hooked in this topic, I will convert my FB using FC's leading igniter for direct fire....just like the way I hooked up my cousin's FB.
My first MSD ignition was set up using one MSD 6AL. The white wire was bridge and connected to both igniters.
Then I switched to YAW style direct fire system.
Now that you got me hooked in this topic, I will convert my FB using FC's leading igniter for direct fire....just like the way I hooked up my cousin's FB.
06-29-04, 04:54 PM
#29
Originally posted by wackyracer
The white wire was bridge and connected to both igniters.
The white wire was bridge and connected to both igniters.
Originally posted by wackyracer
I will convert my FB using FC's leading igniter for direct fire....just like the way I hooked up my cousin's FB.
I will convert my FB using FC's leading igniter for direct fire....just like the way I hooked up my cousin's FB.
06-29-04, 05:00 PM
#30
Here are some pics of the B2000 after I installed DLIDFIS gutting the dead ignitors to use as electrical pass-throughs from the red and green pickup wires over to the HEI ignitors. No need for shielded wires, interestingly. You'd think it's necessary, but I've actually never used shielded wires on all the DLIDFIS installs I've done. The MSD doesn't even require it on its green and purple wires.
Sorry there are no better pics of the wiring to and from the coils etc.
Sorry there are no better pics of the wiring to and from the coils etc.
06-29-04, 05:02 PM
#31
Originally posted by Jeff20B
That's kinda scary to think about. Did both ignitors survive? The 13B powered B2000 was like that and it didn't run very well. Then I got ahold of it and threw in three GM HEI ignitors after the trailing ignitor burned out (leading was already dead and trailing was firing both coils at the same time... no wonder it ran crappy).
Leading coil? I learned the leading ignitor is 'dumb' and relies on the ECU for dwell. Appearantly the traing ignitor is better to use, if you can figure out its mini spaghetti mess of wires. I think I'll use one trailing coil and the trailing ignitor on my 12A. It may not spark reliably at cranking RPM, but it shouldn't prevent the engine from firing up with an MSD on an FC leading coil. I'm sure it'll spark fine at idle and above. I'll use the tach hooked to trailing as an indicator.
That's kinda scary to think about. Did both ignitors survive? The 13B powered B2000 was like that and it didn't run very well. Then I got ahold of it and threw in three GM HEI ignitors after the trailing ignitor burned out (leading was already dead and trailing was firing both coils at the same time... no wonder it ran crappy).
Leading coil? I learned the leading ignitor is 'dumb' and relies on the ECU for dwell. Appearantly the traing ignitor is better to use, if you can figure out its mini spaghetti mess of wires. I think I'll use one trailing coil and the trailing ignitor on my 12A. It may not spark reliably at cranking RPM, but it shouldn't prevent the engine from firing up with an MSD on an FC leading coil. I'm sure it'll spark fine at idle and above. I'll use the tach hooked to trailing as an indicator.
I think ur right...I have to check my notes. in an FC, you have to use 3 MSD boxes (one coil requires 2 while the other only requires 1 MSD). the one I've used is the one with only 1 box...
06-29-04, 05:09 PM
#32
Yeah, three MSDs on an FC which means one MSD for each trailing coil. How ***-backwards is that? Oh well, people that are into that sort of thing also do a lot of dyno testing (dyno queens). I guess I'm just into saving money by not buying things that are unecessary. Heh, I'd also rather run a Whipple Charger instead of a turbo. Call me crazy.
Only one box? The two trailing coils only require one box which houses the ignitor. Or are you talking about the leading coil with its two outputs, yet also only requires one box?
Only one box? The two trailing coils only require one box which houses the ignitor. Or are you talking about the leading coil with its two outputs, yet also only requires one box?
06-29-04, 05:39 PM
#33
Originally posted by Jeff20B
Only one box? The two trailing coils only require one box which houses the ignitor. Or are you talking about the leading coil with its two outputs, yet also only requires one box?
Only one box? The two trailing coils only require one box which houses the ignitor. Or are you talking about the leading coil with its two outputs, yet also only requires one box?
07-01-04, 08:33 PM
#35
Airflow is my life
[QUOTE]Originally posted by Jeff20B
[B] No need for shielded wires, interestingly. You'd think it's necessary, but I've actually never used shielded wires on all the DLIDFIS installs I've done. The MSD doesn't even require it on its green and purple wires.
Actually MSD doesnt call for sheilded wires for 2 reasons I think. First off, their harness wires are twisted together to help sheild it, and second, most cars dont have 2 ignition systems. Think about it.
I have dual 6a's in the racecar, both using the mag triggers. I had some small problems at hi rpms until I bought their sheilded harnesses. I prefer to have it fire off the mag trigger and not use the white wire for one simple reason. You eliminate a source of failure if you eliminate the ignitor from the system.
[B] No need for shielded wires, interestingly. You'd think it's necessary, but I've actually never used shielded wires on all the DLIDFIS installs I've done. The MSD doesn't even require it on its green and purple wires.
Actually MSD doesnt call for sheilded wires for 2 reasons I think. First off, their harness wires are twisted together to help sheild it, and second, most cars dont have 2 ignition systems. Think about it.
I have dual 6a's in the racecar, both using the mag triggers. I had some small problems at hi rpms until I bought their sheilded harnesses. I prefer to have it fire off the mag trigger and not use the white wire for one simple reason. You eliminate a source of failure if you eliminate the ignitor from the system.
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