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dodgerammit wrote:

az chip wrote:Yeah. You have me confused now. Jut read the instructions. LOL.

Reading is what confuses me..... How are you going to do yours?

If you're doing timing control, the distributor pickup wires are what is utilized.
The ECU would have inputs for them, and an output wire for the coil.

If utilizing timing control it is VERY important to follow their instructions to sync the timing how they say to set it up!
Failure to do this could result in engine damage.

The Duraspark uses the exact same style pickup as an MSD distributor, so whatever their instructions say for wiring it up follow the MSD diagram.

Any EFI system needs to be setup & tuned properly, regardless of what you read on web.
There is no such thing as a self tuning system. All EFI systems learn/adjust, but the base setup/tune needs to be correct.
Many folks that have problems initially are due to not following instructions/setup procedures.
Be it GM TBI/FiTech/MSD/Sniper, any of them need it done.

Bill Hamiltion has a very good write-up on here or ifsja, about setting up the Duraspark for EFI.

dodgerammit wrote:

az chip wrote:Yeah. You have me confused now. Jut read the instructions. LOL.

Reading is what confuses me..... How are you going to do yours?

Per the instructions. You have some good questions. I would say to go to the Holley forums to ask them. But the moderator in the Sniper forum there is kinda brutal. He will just tell you to RTFM. I will say go there and read through the threads. That has answered most of mine. The manuals are sometimes not intuitive. The information is there, you just have to link it yourself sometimes.

az chip wrote:

dodgerammit wrote:

az chip wrote:Yeah. You have me confused now. Jut read the instructions. LOL.

Reading is what confuses me..... How are you going to do yours?

Per the instructions. You have some good questions. I would say to go to the Holley forums to ask them. But the moderator in the Sniper forum there is kinda brutal. He will just tell you to RTFM. I will say go there and read through the threads. That has answered most of mine. The manuals are sometimes not intuitive. The information is there, you just have to link it yourself sometimes.

Yeah, I've visited. His favorite words are RTFM. I have RTFM and that is why I am asking for clarity.

From what I gather (and this is also what I've found on GM based TBI) is I can leave the MSD streetfire, do the yellow wire to coil and not have controlled timing, or lose the streetfire, lock the dizzy and let the Sniper do it all.

At least that seems correct to my thinking.

babywag wrote:

dodgerammit wrote:

az chip wrote:Yeah. You have me confused now. Jut read the instructions. LOL.

Reading is what confuses me..... How are you going to do yours?

If you're doing timing control, the distributor pickup wires are what is utilized.
The ECU would have inputs for them, and an output wire for the coil.

If utilizing timing control it is VERY important to follow their instructions to sync the timing how they say to set it up!
Failure to do this could result in engine damage.

The Duraspark uses the exact same style pickup as an MSD distributor, so whatever their instructions say for wiring it up follow the MSD diagram.

Any EFI system needs to be setup & tuned properly, regardless of what you read on web.
There is no such thing as a self tuning system. All EFI systems learn/adjust, but the base setup/tune needs to be correct.
Many folks that have problems initially are due to not following instructions/setup procedures.
Be it GM TBI/FiTech/MSD/Sniper, any of them need it done.

Bill Hamiltion has a very good write-up on here or ifsja, about setting up the Duraspark for EFI.

Yeah, I've already read a bunch on GM based setups. I would basically lock my dizzy and let the computer do it's thing either way.

dodgerammit wrote:

az chip wrote:

dodgerammit wrote:
Reading is what confuses me..... How are you going to do yours?

Per the instructions. You have some good questions. I would say to go to the Holley forums to ask them. But the moderator in the Sniper forum there is kinda brutal. He will just tell you to RTFM. I will say go there and read through the threads. That has answered most of mine. The manuals are sometimes not intuitive. The information is there, you just have to link it yourself sometimes.

Yeah, I've visited. His favorite words are RTFM. I have RTFM and that is why I am asking for clarity.

From what I gather (and this is also what I've found on GM based TBI) is I can leave the MSD streetfire, do the yellow wire to coil and not have controlled timing, or lose the streetfire, lock the dizzy and let the Sniper do it all.

At least that seems correct to my thinking.

From what I have read the yellow wire does not go to the coil when using any CD ignition. There are two distributors that work with the Sniper. The MSD and the Holley. Our Duraspark is not one of them.

Fuel only, no timing control page 24. No yellow wire used with MSD or CD ignition. From what I can see that yellow wire is not used in any CD ignition fuel only or Sniper controlled ignition.

Curious why an MSD would work and a Duraspark would not? They use the exact same style pickup. The MSD 8519 is just a pretty/fancier Duraspark.

A Duraspark doesn’t have a fancy adjustable rotor available like the MSD, but it isn’t hard to make the stator wheel adjustable to accomplish the same thing.

Msd plug and play to the harness. Duraspark you have to splice and solder the right wires iirc or buy an adapter.

ShagWagon wrote:Msd plug and play to the harness. Duraspark you have to splice and solder the right wires iirc or buy an adapter.

lol...so buy the MSD kit PN# 8824 ~$8, or of course you can pickup an MSD 8519 for $300+

I'm a cheapass DIY kinda guy though.

I did it both ways. I soldered it to my OEM one for about two months or so and skimped on the adapter. Then I decided to go total MSD for compatibility and upgraded my distributor as well. Was a lot to learn. I owe it all to the help I got here and other forum.

Got what my wife calls “the lid” back on. Kinda a pain. Lol.


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Oooo purdy.....

Doing fuel pump and wiring. A lot of other fixes and upgrades along the way.


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I have not read this entire thread, so I apologize if I'm stepping on good advice already out there - but I have about 8k miles on my Sniper in my CJ and from what I learned VERY early in running it is that the stock distributor will most likely not be able to handle timing control very well.

Here's why... we basically have Ford distributors running backwards and you can fine tune the reluctor a bit, but due to variances in the pickup coupled with the fact that it runs backwards from what the distributor electronics were designed it will eventually throw the computer off. Mine ran fine at speed in most cases, but at idle it would surge from time to time. Like 1000-1500rpm surge. It was nowhere near safe at a stoplight. I sent them saved info from the dash unit and they examined it and came to this conclusion. Basically the variances are accounted for in the computer up to a certain point and once you reach that mathematical point, it freaks out and sends a load of fuel to the body. It surges, then recalculates immediately back to normal idle. There were three options. Remove timing control, MSD 8519 pro-billet distributor, or the other MSD distributor that runs off electronic eye. Removing timing wasn't an option for me and the electronic eye distributor at the time did not come in an AMC model, so I went with the pro-billet distributor and problem was solved immediately.

Remember too, you set your timing 10 degrees in advance at the crank, then put number 1 at TDC, then set your distributor so 1 is right on the money.

I wonder why the Sniper EFI can't handle the Duraspark distributor, but the GM EFI conversions don't have a problem.

Not arguing with you, just curious. Interesting....

FSJ Guy wrote:I wonder why the Sniper EFI can't handle the Duraspark distributor, but the GM EFI conversions don't have a problem.

Not arguing with you, just curious. Interesting....

No I don't disagree with you...good question. Do the GM based efi's with timing control do the same math with timing? Without timing control, the Sniper and the Duraspark work just fine. The Sniper wants 10 degrees advance at crank with cylinder one on point with rotor, that way it can subtract timing below 10 and then add a little for timing above it. I'm just guessing there's something in that logic that demands more perfection than the reluctor pickup can provide...?

The MSD 8519 & duraspark are virtually identical.
The main difference using an msd is an adjustable rotor is available to ease phasing.
If you search you’ll find tech info on how to properly phase a duraspark for efi.

Of course MSD tech is going to recommend a product their companies sell(msd 8519/8523).
If they made a dual sync for AMC they’d likely say you needed one if them.

If you put an 8519&duraspark on a scope, you would see identical signals.

007 wrote:

FSJ Guy wrote:I wonder why the Sniper EFI can't handle the Duraspark distributor, but the GM EFI conversions don't have a problem.

Not arguing with you, just curious. Interesting....

No I don't disagree with you...good question. Do the GM based efi's with timing control do the same math with timing? Without timing control, the Sniper and the Duraspark work just fine. The Sniper wants 10 degrees advance at crank with cylinder one on point with rotor, that way it can subtract timing below 10 and then add a little for timing above it. I'm just guessing there's something in that logic that demands more perfection than the reluctor pickup can provide...?

GM TBI does the same thing. I set the initial advance timing in the computer for whatever the physical advance is set for.

Beats me why it's not working... (I know, not very helpful....)

What are you going to be using for your 12v ignition source (hot while cranking and ign on)? Thanks!

posulli88 wrote:What are you going to be using for your 12v ignition source (hot while cranking and ign on)? Thanks!

Yellow wire that goes into the ignition relay box mounted on driver's side.

texas993 wrote:

posulli88 wrote:What are you going to be using for your 12v ignition source (hot while cranking and ign on)? Thanks!

Yellow wire that goes into the ignition relay box mounted on driver's side.

Damn. I have a 77 I am not sure I have that wire. Not sure what I am going to use. Thanks for the response.