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lostforawhile
10-04-2010, 05:41 PM
someone may give me an msd box, and i'm wondering how well they work on carb cars, as far as the tach signal, on the carb car it not only drives the tach, but the fuel pump safety relay. has anyone had any problems? do they require the tach adapter? also where does the tach wire tie into the coil negative, is it at the coil or the dizzy? or does it tie in somewhere else,if i have to run the adapter, i need to interupt it

lostforawhile
10-05-2010, 12:27 PM
bump

2oodoor
10-05-2010, 01:24 PM
which box

lostforawhile
10-05-2010, 04:35 PM
msd 6AL and an accell electronic super coil

turabaka
10-05-2010, 07:19 PM
I'm running a 6AL-2 box. Didn't have to use a tach adapter. Fuel pump relay still works like it's supposed to as well. Just wire it up according to the directions that msd supplies.

If you need me to I can go out and double check wire colors and whatnot for you tomorrow.

lostforawhile
10-06-2010, 06:14 PM
any difference you've noticed? this is a battle tested one slightly beat up looking but proven to be reliable

turabaka
10-06-2010, 07:27 PM
any difference you've noticed? this is a battle tested one slightly beat up looking but proven to be reliable

I haven't dyno'd it since the box install, so I have no idea how much extra power it makes. It definitely makes a difference though. Smoothed out the idle considerably, and it seems to pull harder through the whole power band. Minimal gains in hp though I'm guessing.

The funny thing is that in Idaho we have a rule where if you spend a certain amount of money on emissions components you can waive through emissions through they year in case you don't pass. I failed once, and went, eh what the hell, and bought it to waive myself through emissions. Threw it in, and the damned car passed emissions. lol. So, obviously the increased power is giving a much more complete combustion than the stock setup.

lostforawhile
10-06-2010, 07:31 PM
what kind of coil are you running, this comes with an accel electronic super coil which is a u core, the better kind, i was going to mount the box under the dash and the coil in the fender,rather then move the fuse box,just use a feed through tower from the fender to the dizzy

turabaka
10-06-2010, 07:41 PM
I'm running an msd blaster 2 coil. Got the ignition box mounted under the dash as well. heh. Makes it easy to reach the dials if I want to change the 2-step limiter.

lostforawhile
10-15-2010, 06:26 PM
I'm running a 6AL-2 box. Didn't have to use a tach adapter. Fuel pump relay still works like it's supposed to as well. Just wire it up according to the directions that msd supplies.

If you need me to I can go out and double check wire colors and whatnot for you tomorrow.

i may need those, the white wire should be the trigger, i got into an argument with some moron at MSD, he insists our tachs are positive trigger which is bs, and he also insisted that the coil on our cars is in the dizzy? :kekeke: if the white wire is the trigger in then it simply goes to the output on the dizzy correct? dizzy needs power in, ground, and has switched ground out to the coil. coil should be hot all the time when the ignition is on.
the module switches ground. if i hook the tach to the ground out of the module, like it is now, the box should make no difference to the tach or fuel pump relay, since the tach would be reading the outut of the ignition module. and it would be before the box

cygnus x-1
10-15-2010, 08:28 PM
i may need those, the white wire should be the trigger, i got into an argument with some moron at MSD, he insists our tachs are positive trigger which is bs,


Maybe, or maybe not. I can tell you that the tach on my 2g 'lude works with the 5 volt square wave put out by my Megasquirt. This is right to the tach wire that would normally connect to the - side of the coil. So I wouldn't be surprised if it works with the tach out on the MSD.
I know I was definitely surprised when I found out the tach would work with a 5V square wave.




and he also insisted that the coil on our cars is in the dizzy? :kekeke:

That's definitely not true. He's thinking of the 4g Accords.




if the white wire is the trigger in then it simply goes to the output on the dizzy correct? dizzy needs power in, ground, and has switched ground out to the coil. coil should be hot all the time when the ignition is on.
the module switches ground. if i hook the tach to the ground out of the module, like it is now, the box should make no difference to the tach or fuel pump relay, since the tach would be reading the outut of the ignition module. and it would be before the box


I just looked at the instructions for the 6AL, and it looks to me like how you connect it may depend on whether you can get to the magnetic pickup in the distributor. I know on my old dizzy the ignitor module was on the outside and you could tap into the pickup wires directly. But there was a second kind of dizzy where the ignitor is internal. On that one you may have to use the white trigger wire on the MSD. Either way, I would try the tach output on the MSD first for the tach/FPR. If no go then try the output of the stock ignitor (which would also be the trigger input to the MSD). IF still no good then you need a tach adapter. Since it's a capacitive discharge type ignition something tells me you DO NOT want to connect the tach/FPR line to the negative side of the coil like the stock configuration.

Does your dizzy have the ignitor on the outside or inside?

EDIT: One thing I forgot, I'm not using the stock FP relay, so I can't say whether it will work from the MSD or not. My FP is controlled with a separate relay from the Megasquirt.


C|

turabaka
10-15-2010, 09:56 PM
I'll have to double check, but I've pretty sure that I didn't mess with any of the wiring for the tach or the fuel pump. They're exactly in their stock configuration on the coil, and everything operates like it's supposed to.

lostforawhile
10-16-2010, 05:33 AM
Maybe, or maybe not. I can tell you that the tach on my 2g 'lude works with the 5 volt square wave put out by my Megasquirt. This is right to the tach wire that would normally connect to the - side of the coil. So I wouldn't be surprised if it works with the tach out on the MSD.
I know I was definitely surprised when I found out the tach would work with a 5V square wave.





That's definitely not true. He's thinking of the 4g Accords.






I just looked at the instructions for the 6AL, and it looks to me like how you connect it may depend on whether you can get to the magnetic pickup in the distributor. I know on my old dizzy the ignitor module was on the outside and you could tap into the pickup wires directly. But there was a second kind of dizzy where the ignitor is internal. On that one you may have to use the white trigger wire on the MSD. Either way, I would try the tach output on the MSD first for the tach/FPR. If no go then try the output of the stock ignitor (which would also be the trigger input to the MSD). IF still no good then you need a tach adapter. Since it's a capacitive discharge type ignition something tells me you DO NOT want to connect the tach/FPR line to the negative side of the coil like the stock configuration.

Does your dizzy have the ignitor on the outside or inside?

EDIT: One thing I forgot, I'm not using the stock FP relay, so I can't say whether it will work from the MSD or not. My FP is controlled with a separate relay from the Megasquirt.


C|

see in the stock configuration, the igniter would fire the coil directly, if the box is in the middle between the igniter and the new MSD coil, nothing connects to the coil but the box, the tach still connects to the output of the igniter like it used to, but instead of going to the negative side of the coil, it now goes to the input of the msd box. simple right? he simply couldn't get that. he kep saying the coil has 480 volts etc, I couln't get him to understand I wasn't going to hook the tach to the msd coil, DUH!! i polietly told him i'm sure the coil was seperate from the dizzy, thats what the coil wire OUT of the dizzy was, and that odd coil shaped thing on the inner fender, but he kept telling me I was mistaken. :rolleyes:

89T
10-16-2010, 06:27 AM
LOST would you not remove the coil and tie both blues together ,both black/yellow's together.

those will be the input wires for the box.

blues connect to the white(the blue that runs to the fire wall is the tach signal)
blk/yellow connect to red(switched 12v)

heavy red connects to 12v+ batt
heavy black connects to 12- batt

orange connects to aftermarket coil +
blk connects to coil -

lostforawhile
10-16-2010, 08:05 AM
LOST would you not remove the coil and tie both blues together ,both black/yellow's together.

those will be the input wires for the box.

blues connect to the white(the blue that runs to the fire wall is the tach signal)
blk/yellow connect to red(switched 12v)

heavy red connects to 12v+ batt
heavy black connects to 12- batt

orange connects to aftermarket coil +
blk connects to coil -thats what i thought, i'm going to just clean up wiring harness a bit and just tape off the existing hot wire going to the coil, they say to seperate the output wires to the new coil from the others, due to inductive interference, i have a couple of military four pin cannon plugs and panel sockets, i'll install a panel socket in each former ac hose hole, one socket will be the input from the dizzy, other will be the output to the coil, the box is going under my dash. this will make nice clean harnesses and cover up those firewall holes. I have a fuse panel under the passenger side from the battery behind the passenger seat, i can tie the MSD box to the lug coming in from the battery. the instructions for MSD say it has an internal fuse already, and the wire feeding that panel has a primary fuse in the battery box anyway. I'm using an MSD blaster GM coil, after searching about a hundred cars at the yard yesterday I finally found a factory GM coil with the proper bracket, it was in a minivan sitting up on tires tilted about 45 degrees, so not fun to crawl into the downtilted side, someone idiot had already cut off the gm connector though, I need that connector to be able to plug in my coil. :burn: i couldn't find another one anywhere. I was trying to figure out how to connect the coil to the dizzy, I have accell wires, I got a V8 set, and split it, custom length wires, all the factory coil to dizzy wires are female connectors, and the gm coil is a male connector, it finally dawned on me, the msd connector looks exactly like a spark plug sticking out of the coil, and sure enough a spark plug end of an accell wire cliped right on, nice tight watertight fit. all i have to do is cut it to length, add a terminal, and a 90 degree boot to plug right into the dizzy. I'll have pictures later

jcrockett
10-16-2010, 08:15 AM
Is there a big benefit on the carbed engine?

lostforawhile
10-16-2010, 08:26 AM
Is there a big benefit on the carbed engine?

you have multiple sparks at lower RPM, it gives you a cleaner more complete burn and better idle, also since it's a CD type of box, your spark output doesn't drop off at higher RPM's, with an inductive type system, the coil doesn't have time to charge between firings, with a CD type system it doesn't have to, the box fires the coil at full voltage. they are useful on any type of engine, carbed or fuel injected.

Xaisk
10-16-2010, 08:58 AM
erm.. scratch that question. I got it figured out =D installed the MSD SS blaster coil today. Ive noticed a SIZEABLE increase in acceleration which makes me happy in my pants.

Still need some NGK spark wires and lazer iridium plugs before im satisfied with it.

My spark plug wires are ghetto old ones and one does even match and is being held in with tape. The plugs are the cheapest ones I could find.

lostforawhile
10-16-2010, 03:03 PM
erm.. scratch that question. I got it figured out =D installed the MSD SS blaster coil today. Ive noticed a SIZEABLE increase in acceleration which makes me happy in my pants.

Still need some NGK spark wires and lazer iridium plugs before im satisfied with it.

My spark plug wires are ghetto old ones and one does even match and is being held in with tape. The plugs are the cheapest ones I could find.

don't bother with the expensive plugs, use the regular V power, you might be able to open up the gap some though. those are the plugs this engine is happiest on. I have a full set of Nappa wires from when i changed mine out, they look like oem wires, you can have them for shipping

Xaisk
10-16-2010, 05:34 PM
don't bother with the expensive plugs, use the regular V power, you might be able to open up the gap some though. those are the plugs this engine is happiest on. I have a full set of Nappa wires from when i changed mine out, they look like oem wires, you can have them for shipping

Thanks for the offer lost. I think im going to go with the NGK ones just because of the cosmetics =P Even though im avoiding trying to be ricer.. making my engine bay look nice doesnt count towards that. Im going for the sleeper look.

lostforawhile
11-23-2010, 11:33 PM
I think i figured out why the tach triggers on the low voltage out from the msd box, tach terminal, the coil is triggered by the blue wire, triggered ground from the dizzy, but inside the coil itself, between that wire and the blue wire out to the tach,fuel pump relay, multi function box, ECU or emissions control box ,fan timer, and ac delay box, yes it goes to all those and more, there is a resistor, so it may be dropped down to 5 volts itself ,if you measured between hot and that ground.

lostforawhile
12-07-2010, 12:34 PM
ok, you need the 2.2k resistor between the blue wire out on the dizzy, and where it goes into the car, in the stock setup, it's inside of the coil, but the trigger into the MSD box needs to be BEFORE the resistor, you just need to tap off an extra wire is all. if someone wants to send me a known bad coil, I'll cut it open to show the inside and where the resistor is. I don't want to cut up a good one, since someone might need it someday

lostforawhile
12-27-2010, 04:33 PM
hey has anyone lengthened the wires going to the coil without an issue? I ended up mounting the entire thing to a plate under the passenger seat, the factory high voltage wires almost reach the firewall, i may need to extend them at most a foot, it says in the online manual they can be extended but it doesn't specify how far, just to solder and seal them. I know the high voltage line will run on one side of the floor pan, and the trigger signal on the other, and both are getting copper tape over them, to protect from receiving and causing interference, the factory wires are run in a heavy rubber tube, so I'll duplicate that with rubber vacuum line. I have some military cannon plugs, the older metal ones, so i'll use one to connect the high voltage wires at the box and make the wire run permanent all the way to the coil, no splices until it reaches the coil connector , then they will be soldered of course

lostforawhile
12-28-2010, 01:59 PM
Ok I talked to MSD techncical support, and it's no issue to lengthen the wires, I just have to go one gauge larger to do so. I had a nice military cannon connector, and somehow the two halves have permanently anchored themselves together, it was fine and i screwed it together, now it refuses to come apart, nothing will unscrew it, visegrips, nothing, wierd, so i used another one of these heavy connectors from a Honda ABS system, good watertite connectors, and they also have a plastic bridge between the terminals, which will prevent arcing, that is over 600 volts from the msd box to the coil, requires careful insulation and connectors.