Msd Blaster 2 Coils
05-07-2004, 08:09 AM
#31
Senior Member
Join Date: Nov 2003
Posts: 480
One reluctor I came across is the other way around - fast rise, then slow drop off.
It was in a 1980 style distributor that was on some JDM mystery motor (13B 4 port,
carb'ed, electronic ignition, nitrided housings).
If the white wire on the trail ignitor is not connected, it should fire C1 every time. You might try grounding it. If it is connected to +, C2 will fire instead.
'86 ignitors need a stronger trigger signal than J109's because they weren't really
designed for use with a magnetic trigger. They use a square wave trigger from
the ECU, 5 volts typically but 12 seems okay. That's why I recommended using
the J109 and tweaking the output. (Incidentally, grounding one of the pickup coil
wires won't reduce sensitivity - one of the MSD mag pickup wires is in fact grounded - green I think). My other concern was what happens at high RPM - the
mag pickup signal gets quite strong - I'm not totally sure the 86 ignitor would
deal with that happily.
It was in a 1980 style distributor that was on some JDM mystery motor (13B 4 port,
carb'ed, electronic ignition, nitrided housings).
If the white wire on the trail ignitor is not connected, it should fire C1 every time. You might try grounding it. If it is connected to +, C2 will fire instead.
'86 ignitors need a stronger trigger signal than J109's because they weren't really
designed for use with a magnetic trigger. They use a square wave trigger from
the ECU, 5 volts typically but 12 seems okay. That's why I recommended using
the J109 and tweaking the output. (Incidentally, grounding one of the pickup coil
wires won't reduce sensitivity - one of the MSD mag pickup wires is in fact grounded - green I think). My other concern was what happens at high RPM - the
mag pickup signal gets quite strong - I'm not totally sure the 86 ignitor would
deal with that happily.
05-07-2004, 12:19 PM
#32
Senior Member
Join Date: Nov 2001
Posts: 2,284
Where I said
I meant to say C2.
Ok, I'll try the ground or + connection on the white wire and see what it does for me.
Hey, on that mystery JDM 13B, were the mechanical advance slots in opposite directions compared to a GSL-SE dizzy? I've seen one like that once. It's in a custom built four port 13B in a B2000. I just remember looking down into the dizzy and noticing it curved backwards compared to what I was used to. I don't remember which style of reluctor it had. Also, do you know if it has R5 side plates? I've got two JDM four port 13Bs that are nitrided with only four freeze plugs in the rear plate. Is it missing an oil pressure hole? Does it have a what looks like an aftermarket temp sensor in the front plate down near the leading plug?
You can install the reluctor upside down if you wanted to.
The Hanshin on C1 no longer sparks.
Ok, I'll try the ground or + connection on the white wire and see what it does for me.
Hey, on that mystery JDM 13B, were the mechanical advance slots in opposite directions compared to a GSL-SE dizzy? I've seen one like that once. It's in a custom built four port 13B in a B2000. I just remember looking down into the dizzy and noticing it curved backwards compared to what I was used to. I don't remember which style of reluctor it had. Also, do you know if it has R5 side plates? I've got two JDM four port 13Bs that are nitrided with only four freeze plugs in the rear plate. Is it missing an oil pressure hole? Does it have a what looks like an aftermarket temp sensor in the front plate down near the leading plug?
You can install the reluctor upside down if you wanted to.
05-07-2004, 01:06 PM
#33
Senior Member
Join Date: Nov 2003
Posts: 480
Well, I can't say anything on the advance slots, as most of my distributors have
been apart and then reassembled, so stuff has been shuffled. I think that one
right now has a welded shaft from a 12A distributor.
Not sure what side plates it had, as they've been shuffled around; however, I
just recently replaced a rear plate on one of my motors and found some
interesting things. Near the oil filter, some rear housings (typically the old
ones) have a thick rib at the dowel pin boss and some do not. Well this housing
has a distinctive thinner/bent rib in that area. The housings without that rib will
crack under boost (up to 350 HP is probably safe). Anyway I figured I'd try
it. After I put the engine in the car, I went to install the oil pressure sender,
and wouldn't you know it? No hole!
On another note, I stumbled across a Diamond coil yesterday and checked it -
about 1 ohm primary resistance, as opposed to 1.5 I had measured on a
no-name coil. That being the case, a 0.7(?) ohm Blaster isn't as far off as I
had thought. Here's some info from memory:
Primary resistance: Diamond 1.0 Blaster 0.7
Secondary resistance: Diamond 8k Blaster 5k
total primary inductance: Diamond 5.1mH Blaster 4mH
primary leakage imductance: Diamond 1.1 mH Blaster 0.5 mH
been apart and then reassembled, so stuff has been shuffled. I think that one
right now has a welded shaft from a 12A distributor.
Not sure what side plates it had, as they've been shuffled around; however, I
just recently replaced a rear plate on one of my motors and found some
interesting things. Near the oil filter, some rear housings (typically the old
ones) have a thick rib at the dowel pin boss and some do not. Well this housing
has a distinctive thinner/bent rib in that area. The housings without that rib will
crack under boost (up to 350 HP is probably safe). Anyway I figured I'd try
it. After I put the engine in the car, I went to install the oil pressure sender,
and wouldn't you know it? No hole!
On another note, I stumbled across a Diamond coil yesterday and checked it -
about 1 ohm primary resistance, as opposed to 1.5 I had measured on a
no-name coil. That being the case, a 0.7(?) ohm Blaster isn't as far off as I
had thought. Here's some info from memory:
Primary resistance: Diamond 1.0 Blaster 0.7
Secondary resistance: Diamond 8k Blaster 5k
total primary inductance: Diamond 5.1mH Blaster 4mH
primary leakage imductance: Diamond 1.1 mH Blaster 0.5 mH
05-07-2004, 02:18 PM
#34
Senior Member
Join Date: Nov 2001
Posts: 2,284
Hey, the white wire did cause the other one to spark! It's still random though. I may be getting interference from the battery charger I'm using. I measured the voltage output and it's 11.5, 10.5 and 7.4 (on the 6 volt setting). The ignitor still works, even at 7.4 volts, and it still sparks randomly. At least I know it will spark below 12 volts.
Ok, I just tested it with a row of 9 D cell batteries that went from 12.84 down to 11.96 (they're old). I got the ignitor to spark reliably evey time I'd tap the speaker. It also seemed to work a lot better with the pickup and a screwdriver pulled quickly from the little rectangular 'core' at the center of the pickup coil. The remaining question is how well it will work in a running car. Good thing it's on trailing, right?
I noticed it uses more power when the white wire is hooked to +. The spark isn't any bigger, but the voltmeter goes down when connected and back up when grounded or disconnected. I think for general use, the white wire needs to be grounded or left disconnected. It might lead to less heating of the ignitor in the long run.
Ok, I just tested it with a row of 9 D cell batteries that went from 12.84 down to 11.96 (they're old). I got the ignitor to spark reliably evey time I'd tap the speaker. It also seemed to work a lot better with the pickup and a screwdriver pulled quickly from the little rectangular 'core' at the center of the pickup coil. The remaining question is how well it will work in a running car. Good thing it's on trailing, right?
I noticed it uses more power when the white wire is hooked to +. The spark isn't any bigger, but the voltmeter goes down when connected and back up when grounded or disconnected. I think for general use, the white wire needs to be grounded or left disconnected. It might lead to less heating of the ignitor in the long run.
05-07-2004, 02:28 PM
#35
Senior Member
Join Date: Nov 2001
Posts: 2,284
I bet you've got an R5 plate there. Welcome to the club. 
Then again, '79-'80 didn't have an oil pressure switch or guage either.
I tried my hand at drilling and tapping the unmachined flat area on one of my R5 plates. It turned out great. I hit the oil 'galley' perfectly centered left-to-right, but ended up a little lower than the middle of the flat spot (big deal). I cut some 1/8x27 NTP threads for pretty much any aftermarket guage. I threw an NPT plug in it for the GLC project, but I'll pull it back out for the REPU project once the 20B is ready.
I have one Y and one R5 rear plates sitting nearby. I'll look for the rib near the upper dowel pin hole.
So the Diamond is actually not too bad of a coil to use? I like them better than Hanshin and Bosch.
I tried my hand at drilling and tapping the unmachined flat area on one of my R5 plates. It turned out great. I hit the oil 'galley' perfectly centered left-to-right, but ended up a little lower than the middle of the flat spot (big deal). I cut some 1/8x27 NTP threads for pretty much any aftermarket guage. I threw an NPT plug in it for the GLC project, but I'll pull it back out for the REPU project once the 20B is ready.
I have one Y and one R5 rear plates sitting nearby. I'll look for the rib near the upper dowel pin hole.
So the Diamond is actually not too bad of a coil to use? I like them better than Hanshin and Bosch.
05-07-2004, 02:45 PM
#36
Senior Member
Join Date: Nov 2001
Posts: 2,284
I just got back from looking at severla rear plates. In Mazda's attempt to lighten their castings for their 101HP (or whatever) 12As, there is no rib on 12A Y castings. There is a straight thick rib on 3B castings (old non nitrided '74). There is a curved rib on the R5 casting in my GLC. I've got two more to look at in a minute. The 20B has a thick rib that resembles the 3B casting.
Going to look at three or four more rear plates...
Two more nitrided R5s also have the curved rib. The non nitrided R5? '76 Cosmo plate does have an oil pressure guage hole and a thick rub (I'd know which casting it is if I removed the upper inspection cover). I've seen non nitrided R5 plates before which have 5 freeze plugs whereas nitrided ones have four.
Lastly, my '71-'73 twin dizzy 12A has a rib.
So far, the only two that don't have ribs are from two RX-7 12As. One was and '82 or older because it has a pressed in short heater core tube. The other in '83 or later because it has a T shaped heater core hose for the beehive.
So how much power do you think an older R5 or 3B plate can take? How could a newer R5 take with its thinner, curved rib?
Wow, this post got way off topic.
Going to look at three or four more rear plates...
Two more nitrided R5s also have the curved rib. The non nitrided R5? '76 Cosmo plate does have an oil pressure guage hole and a thick rub (I'd know which casting it is if I removed the upper inspection cover). I've seen non nitrided R5 plates before which have 5 freeze plugs whereas nitrided ones have four.
Lastly, my '71-'73 twin dizzy 12A has a rib.
So far, the only two that don't have ribs are from two RX-7 12As. One was and '82 or older because it has a pressed in short heater core tube. The other in '83 or later because it has a T shaped heater core hose for the beehive.
So how much power do you think an older R5 or 3B plate can take? How could a newer R5 take with its thinner, curved rib?
Wow, this post got way off topic.
05-07-2004, 07:37 PM
#37
Senior Member
Join Date: Nov 2003
Posts: 480
>> I noticed it uses more power when the white wire is hooked to +.
Probably a clamp diode on the input - maybe 12v on that wire is too
much.
>>So the Diamond is actually not too bad of a coil to use?
Generally lower resistance is better, unless the ignitor has some
minimum requirement. The Blaster is the only canister type coil I
have tested with a decently low leakage inductance. More leakage
inductance=more time to saturate without gaining anything. The
Blaster SS, on the other hand, is probably best used with a CDI
because of the higher indutance - too much for high RPM on an inductive
ignition.
>>So how much power do you think an older R5 or 3B plate can take?
Probably as much as you want. There was a guy in Florida running
8.20's on a 12A using 79/80 side housings.
>>How could a newer R5 take with its thinner, curved rib?
Not sure. I haven't broken mine yet, although I haven't been running
it hard either. I know the last housing that didn't have a rib broke
the first time I floored it. I'm told that extra dowel pins can be
installed, allowing the use of any plate. Also some of the racers
plug that oil passage altogether and run an external oil line to
the front housing. Speaking of which, front housings can crack
also but I haven't witnessed it.
Mazda sure has a habit of removing casting from all the wrong places -
ever seen a fuel injected center housing that can be ported like a
carb'ed one? At least they seem to have fired the guy who was
designing their intake manifolds and got someone competent.
Probably a clamp diode on the input - maybe 12v on that wire is too
much.
>>So the Diamond is actually not too bad of a coil to use?
Generally lower resistance is better, unless the ignitor has some
minimum requirement. The Blaster is the only canister type coil I
have tested with a decently low leakage inductance. More leakage
inductance=more time to saturate without gaining anything. The
Blaster SS, on the other hand, is probably best used with a CDI
because of the higher indutance - too much for high RPM on an inductive
ignition.
>>So how much power do you think an older R5 or 3B plate can take?
Probably as much as you want. There was a guy in Florida running
8.20's on a 12A using 79/80 side housings.
>>How could a newer R5 take with its thinner, curved rib?
Not sure. I haven't broken mine yet, although I haven't been running
it hard either. I know the last housing that didn't have a rib broke
the first time I floored it. I'm told that extra dowel pins can be
installed, allowing the use of any plate. Also some of the racers
plug that oil passage altogether and run an external oil line to
the front housing. Speaking of which, front housings can crack
also but I haven't witnessed it.
Mazda sure has a habit of removing casting from all the wrong places -
ever seen a fuel injected center housing that can be ported like a
carb'ed one? At least they seem to have fired the guy who was
designing their intake manifolds and got someone competent.
05-08-2004, 02:10 AM
#38
Senior Member
Join Date: Nov 2001
Posts: 2,284
Check this out. http://www.pixagogo.com/9194155351 It's an attempt at trailing direct fire. Of course the guy screwed up when he chopped both reluctors because he should have left the leading one intact. Live and learn I suppose.
That's not the reason why I'm showing you this. Have you seen the direction of the reluctors? They're opposite each other. It works in his setup though because the one on top is upside down.
That's not the reason why I'm showing you this. Have you seen the direction of the reluctors? They're opposite each other.
05-08-2004, 10:44 AM
#39
Senior Member
Join Date: Nov 2003
Posts: 480
Sort of looks like they'd go either way... What I'd probably try would
be to get one of those points to electronic kits that uses a photo
interrupter disc, and modify the disc to provide the select signal
to an 86 trail ignitor.
Off topic? It's the internet isn't it! Well someone earlier mentioned
maybe getting an MSD for better gas mileage. It might be worthwhile
to check out eBay and find some off brand CDI (Tiger, etc) for nothing.
At like $10 a piece you could get one for the trailing too - I think
there is something to be gained here but haven't proven it yet.
Of course the cheap ones don't multispark, but that's done by around
3K anyway (and costs alot vs a cheapy one). Might be worth a shot.
be to get one of those points to electronic kits that uses a photo
interrupter disc, and modify the disc to provide the select signal
to an 86 trail ignitor.
Off topic? It's the internet isn't it! Well someone earlier mentioned
maybe getting an MSD for better gas mileage. It might be worthwhile
to check out eBay and find some off brand CDI (Tiger, etc) for nothing.
At like $10 a piece you could get one for the trailing too - I think
there is something to be gained here but haven't proven it yet.
Of course the cheap ones don't multispark, but that's done by around
3K anyway (and costs alot vs a cheapy one). Might be worth a shot.
05-08-2004, 11:24 AM
#40
Senior Member
Join Date: Nov 2001
Posts: 2,284
Hmm, those optical points conversion kits might work pretty well for trailing direct fire. It would just take a little minor detail work. I'm sure somebody's going to try it eventually.
About the MSD going from multi to single sparks around 3k, I noticed there is not mention of when in the RPM range it goes to single sparks in the instruction booklet. I wonder why there is no mention of it. At least the instructions for how many wires to clip for the rev limiter of the 6AL are decently descriptive. Also, this 3k changeover would be different for V6 and V8 engines. Wouldn't it be at 1500RPM on a V8? Sorry, it's still early here. (this is supposed to be a yawn)
Oh, I almost forgot to mention that I have a Chrysler electronic ignition box. It allows points of a magnetic pickup to trigger it. Do you think it is as good an ignitor as the stock trailing ignitor for a trailing coil?
About the MSD going from multi to single sparks around 3k, I noticed there is not mention of when in the RPM range it goes to single sparks in the instruction booklet. I wonder why there is no mention of it. At least the instructions for how many wires to clip for the rev limiter of the 6AL are decently descriptive. Also, this 3k changeover would be different for V6 and V8 engines. Wouldn't it be at 1500RPM on a V8? Sorry, it's still early here. (this is supposed to be a yawn)
Oh, I almost forgot to mention that I have a Chrysler electronic ignition box. It allows points of a magnetic pickup to trigger it. Do you think it is as good an ignitor as the stock trailing ignitor for a trailing coil?