Pirate 4x4 banner

1 - 20 of 39 Posts

·
turd-polish-a-go-go
Joined
·
1,073 Posts
Discussion Starter #1 (Edited)
at Pappa Smurf's request, i've done a short writeup on wiring the MSD 6A ignition box to a G13/G16k.

everythign i own has an MSD box in it. they smooth out the idle (allowing for reliable idling at 600 RPM), noticeably boost bottom end response, and improve mileage. i don't work for them, but i should, i've probably installed a dozen of these suckers. the MSD signals the coil to fire multiple sparks over a longer duration under 3000 RPM. the implications should be obvious. NOTE: you will need a better coil. there is a list of compatible coils in the manual, but any hot coil will do. i use an accel supercoil in my samurai because that's what i had at the time. MSD blaster coils are good, also works with HEI, and summit brand cannister coils, etc.

installing the box on a carbureted engine is not rocket science. the sam/track/kick distributors are hall-effect magnetic pickup types, so they can trigger anything. just hook it up like the diagram says. You must abandon the condenser (the second wire on coil +) or you'll have problems.

pay attention- select the your vehicle's configuration from below, and follow those tips.

-get switched power from either Blk/W wire that previously was connected to coil + OR the distributor pickup. they are the same circuit, spliced upstream, to IGN ON and START ON. run your main pwr and gnd directly to the battery. trigger and coil connections are straight from the diagram, too easy.

-if you have a factory tach and a weber, OR a factory tach with a computer-controlled fuel system (factory TBI or hitachi), you run the tach signal wire from the MSD to the BROWN wire. both the factory tach and the computer will receive a square-wave signal for RPM.

-if you have an aftermarket tach with a weber, just run the tach signal wire from the MSD box to the aftermarket tach.

-if you have swapped-in TBI OR computer control with an aftermarket tach, you must build a diode harness. that's the big trick. the diodes are just a precaution, feedback from the computer or tach (since you are splitting the signal) might interfere and screw things up for you.

-if you have swapped-in TBI with a factory tach, you need a diode harness attached to the factory tach and to the tach signal input on the TBI computer.

diagrams:

MSD box to magnetic-pickup distributor:



wiring notes for samurai:



diode harness:



everything clear as mud?
 

·
turd-polish-a-go-go
Joined
·
1,073 Posts
Discussion Starter #2 (Edited)
shoddy pics for reference-

MSD box:



Distributor wire identification:
(ignore the wiring, it's super customized :flipoff2: )




any questions?

-LBS
 

·
Registered
Joined
·
1,186 Posts
Wow! That was very informative and well wrote!

These units can be bought brand new at your local parts store from $160 all the way to $630. Look on Ebay or local classifieds and you could probably find this setup for $100.

How about a 2-step write-up ;)

And that's a very clean firewall.
 

·
Registered
Joined
·
2 Posts
All you did to hook up to the distributor was remove the plug that was there and then plug the violet into the black wire and the green into the other one on the distributor? I tried that and it does not seem to work.

i have noted that I only have 4volts comming from the violet wire on the MSD, and the black wire from the none distributor side of the distributor plug appears to have 12 volts. I am wonder if you did something special with the wireing there, or if maybe my MSD ignition module is bad?
 

·
turd-polish-a-go-go
Joined
·
1,073 Posts
Discussion Starter #5
check your coil connections, make sure you removed the condenser, and use a MSD or Accel coil that can handle the saturation duty cycle that the MSD puts through it. you can try reversing the green and violet, but i don't think it will do anything. the distributor triggers the box by a change in the magnetic field at the pickup, which is (for the most part) a square wave. you can test the pickup with an analog multimeter or a digital with a simulated analog readout like the Fluke 88. make sure you set your timing again after the box is installed, and check your firing order. you can try touching the plug wire terminal to your tongue and cranking the engine to determine if you have spark. or not.

MSD has excellent telephone tech support if you are still having issues.
 

·
Registered
Joined
·
1,470 Posts
You can try touching the plug wire terminal to your tongue and cranking the engine to determine if you have spark. or not.
Let me know how that works for you...:eek: :D I tried to hook a Digital 6 box up to my 16V but MSD said it wasnt possible due to the coil in the disty...:confused:
 

·
Registered
Joined
·
3,809 Posts
Thats what I was going to ask, can this be done on a 16v from a 95?
 

·
Registered
Joined
·
2 Posts
check your coil connections, make sure you removed the condenser, and use a MSD or Accel coil that can handle the saturation duty cycle that the MSD puts through it. you can try reversing the green and violet, but i don't think it will do anything. the distributor triggers the box by a change in the magnetic field at the pickup, which is (for the most part) a square wave. you can test the pickup with an analog multimeter or a digital with a simulated analog readout like the Fluke 88. make sure you set your timing again after the box is installed, and check your firing order. you can try touching the plug wire terminal to your tongue and cranking the engine to determine if you have spark. or not.

MSD has excellent telephone tech support if you are still having issues.
That was my thinking. I'm trying to do this on an 87 carburated Zoo. I just called MSD and they told me that I have to use a different wireing setup then you used. I was told That I dont use the voilet and green that I need to use the white wire off the wire that used to go to the coil from the computer.

the MSD dood told me that i have <spelled wrong> Hilux pickup that does not work with MSD??
 

·
turd-polish-a-go-go
Joined
·
1,073 Posts
Discussion Starter #9
really? i thought the pickups were the same. my 8v distributors have pickups that look just like HEI. i've hooked up at least three of them to samurais, and a half dozen more to other vehicles. hmmm.

other option is to get a flying magnet position sensor out of the junkyard and make it fit. EDIS (missing tooth wheel type) won't work without the circuitry to back it up, but flying magnet types produce the right kind of signal for the green/violet wires. you can get them off of a crank, but better yet use a cam position sensor from another 4-banger. tack it to your cam timing sprocket, knock out the hole in your timing cover, and fab a simple little bracket for the pickup that is adjustable so you can set timing. advance will still be controlled at the distributor, since the MSD only triggers the coil.

you can find info on which vehicles have cam position sensors that you can use on the megasquirt forums, or elsewhere on the net. you can even make your own by carefully drilling your cam sprocket and jb-welding in four magnets (from a surplus warehouse) and using only the pickup from a later model vehicle.

it can be done, easily for some, more complicated for others. i would call that an easy mod.
 

·
Registered
Joined
·
1,017 Posts
everything I read led me to believe the 6a needed something else to make it work so I gave up on the idea. very good write up and I may just get me one of those. thanks!!
 

·
Registered
Joined
·
837 Posts
i have hyfire 6a new in box that has never been put to use, it's pretty much the same as the msd in my ranchero. i may have to put it in my rig even though petroworks once told me there was nothing to gain. i already put in a jacobs coil and that made a difference. thanks for the write up, i would have probably missed the diode part.
 

·
turd-polish-a-go-go
Joined
·
1,073 Posts
Discussion Starter #13
the diodes are a precaution to avoid any interference or backfeeds, so that both the tach and the computer get a clean signal. nuthin' fancy, i just don't like splitting signal wires.
 

·
turd-polish-a-go-go
Joined
·
1,073 Posts
Discussion Starter #14
i've got your answer!

you CAN use a VR (variable reluctor) distributor to trigger your MSD, and it's cheap, too.

VR pickups generate an AC signal. this method will convert your AC wave to a (sort of) square wave at the zero crossings, which is what your MSD box wants to 'see'.

obtain a GM HEI 4-pin control module from your parts bin (in my case) or pocket one from your local overpriced you-pull-it yard. you can buy one new from napa #ECHTP45 or niehoff DR400, but these things don't go bad. the 4-pin modules were used from '76 to the mid '80s.



the four pins are labeled and connected IN THE DONOR CAR as follows-
W -pickup (+)
G -pickup (-)
C -coil neg
B -coil pos

what you're gonna do is hook up the W and G to your distributor signal output. solder a 470-ohm 0.5-watt resistor between contacts C and B. connect B to switched hot, and send C to your msd box. the resistor provides some load for the conditioner circuit. screw the HEI module's bottom against a ground, like your firewall, so it can dissipate heat.

check your timing. it may be a bit out of phase. if you can't get it to time, reverse the leads to the W and G terminals, it might help get in sync. it would be a good idea at this point to check that the rotor is lining up with the center of the distributor cap terminal at TDC by drilling a hole in an old cap and using a flashlight. if it is out of whack from a timing shift from the conditioning circuit you just built, pull the distributor and shift a tooth to get things lined up right. you'll know that this needs to be done if you don't have enough adjustment on one side or the other to get proper spark. for your engine's sake, it might be best to remove the plug wires from cyls. 2-4 and just read time off of #1 with your timing light until you verify that everything is in time.

you're welcome.
 

·
Registered
Joined
·
15 Posts
Hello Sambo! Has this been tested? I need to use a 4 pin setup on a MSD box with a bad magnetic input but the white wire is fine, this would solve my problem! I just don't want to mess anything up and the resistor seems a bit strange?

I REALLY appreciate your input!

i've got your answer!

you CAN use a VR (variable reluctor) distributor to trigger your MSD, and it's cheap, too.

VR pickups generate an AC signal. this method will convert your AC wave to a (sort of) square wave at the zero crossings, which is what your MSD box wants to 'see'.

obtain a GM HEI 4-pin control module from your parts bin (in my case) or pocket one from your local overpriced you-pull-it yard. you can buy one new from napa #ECHTP45 or niehoff DR400, but these things don't go bad. the 4-pin modules were used from '76 to the mid '80s.



the four pins are labeled and connected IN THE DONOR CAR as follows-
W -pickup (+)
G -pickup (-)
C -coil neg
B -coil pos

what you're gonna do is hook up the W and G to your distributor signal output. solder a 470-ohm 0.5-watt resistor between contacts C and B. connect B to switched hot, and send C to your msd box. the resistor provides some load for the conditioner circuit. screw the HEI module's bottom against a ground, like your firewall, so it can dissipate heat.

check your timing. it may be a bit out of phase. if you can't get it to time, reverse the leads to the W and G terminals, it might help get in sync. it would be a good idea at this point to check that the rotor is lining up with the center of the distributor cap terminal at TDC by drilling a hole in an old cap and using a flashlight. if it is out of whack from a timing shift from the conditioning circuit you just built, pull the distributor and shift a tooth to get things lined up right. you'll know that this needs to be done if you don't have enough adjustment on one side or the other to get proper spark. for your engine's sake, it might be best to remove the plug wires from cyls. 2-4 and just read time off of #1 with your timing light until you verify that everything is in time.

you're welcome.
 

·
turd-polish-a-go-go
Joined
·
1,073 Posts
Discussion Starter #16
the circuit needs to see a load, hence the resistor. yes it has been tested, it's a common megasquirt trick. converts a wave to a pulse.
 

·
Registered
Joined
·
15 Posts
I cannot say thank you enough! I really appreciate the wisdom! I get my new HEI tomorrow and I will be doing a remote coil with a HVC box and coil. Thanks a million!!!:D

the circuit needs to see a load, hence the resistor. yes it has been tested, it's a common megasquirt trick. converts a wave to a pulse.
 

·
Registered
Joined
·
2,419 Posts
What year samurai are you guys have problems with i wonder if there is a difference between years.
 
1 - 20 of 39 Posts
Top