Holley sniper

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1969cuda340

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After reading everything about hooking up the Holley sniper I’ve decided to eliminate the 2 prong ballast tie them together and tie into that for my power to the sniper. My question is should I run a diode a relay or just leave it like that.
 
At least one on here claimed to have a problem with power, but it may be he had a "loose" ignition switch. What you describe is exactly what I'd start with
 
I show power drop 12v to 9v so with a diode I think I’d be able to keep the 12 volts.
 
Not sure why you think you need a diode? and yes, all diodes drop across a conducting junction, but it's normally up to about .7V
 
By passing the ballast. Jumping it. I go from 12 volts to 9 while cranking. I think I’ll run a toggle from battery power. I’m over it
 
For my FiTech I used the ign wire at the ballast to trigger a relay for my main power to the ECU directly from the battery.
I made a little mini-harness with blade connectors to bypass the ballast and since my ECU controls timing I also removed the harness for the ignition box.

If your battery drops to 9v while cranking, your battery is likey shot or too small.
 
I know nothing about your car/ system. But if you are dropping that much on the ignition line, YOU ARE LIKELY to have SERIOUS overvoltage / charging problems. Find out where the drop is coming from. If the ignition line is dropping from the battery/ through the bulkhead/ ignition switch/ back through the bulkhead, the VR will "overvoltage." One way to fix that is to "back up" (on the EFI) Take the blue "run" wire and cut it coming out of the bulkhead before it branches off

Use the bulkhead end to trigger a relay, and feed the relay off a large no12 fused/ breaker wire off the starter relay "big post." Connect the engine bay cut end to the load contact.
 
You cannot just take a ratty, old harness/ system that already has built-in problems and expect an EFI system to work
 
For my FiTech I used the ign wire at the ballast to trigger a relay for my main power to the ECU directly from the battery.
I made a little mini-harness with blade connectors to bypass the ballast and since my ECU controls timing I also removed the harness for the ignition box.

If your battery drops to 9v while cranking, your battery is likey shot or too small.
I think you’re right about the battery. I was just telling the wife that. I ran a toggle guess that will help with an anti theft device. I think I’ll still bypass the ballast. Should I run a diode across it?
 
I think you’re right about the battery. I was just telling the wife that. I ran a toggle guess that will help with an anti theft device. I think I’ll still bypass the ballast. Should I run a diode across it?
You need to CHECK it. Get your meter and get to work. Does this sound harsh? NO. It means it is what you have to do. Forget diodes

Clip the meter to the battery. Note the reading. Turn key to "run" Note the reading. Ground the coil wire so it will not fire. Twist to start and crank, and note the reading

Now clip the meter to the coil + wire. Take the same readings, key in "run" note reading and key in "start" and cranking note the reading.

There should not be more than say, .3V between the battery readings and the coil wire readings.

The battery should be 12.6 fully charged. The battery should not sag below 10.5 minimum when cranking.
 
I think you’re right about the battery. I was just telling the wife that. I ran a toggle guess that will help with an anti theft device. I think I’ll still bypass the ballast. Should I run a diode across it?

I don't understand why you would want a diode? What would it do?
If you're running the OEM ignition then you should probably keep the ballast functional. If you have a system that dies not require a ballast, or you're going to control timing through the sniper, the you can likely bypass it.
We don't have enough information about your install to make the call.
 
I can see using a diode on relay coil, to slow down relay contact release on start to run transition. Diode polarity is important, it must be reverse biased, cathode at + terminal of relay coil.
Addition of diode may provide about 100ms of release delay for transition, for a worn ignition switch.
 
^^Except most all Bosch relays already have diodes internally^^

Here's a question, tho, Dave........if a relay has no internal diode, and you add an external one, can a diode in series with a resistor increase release delay time?
 
Forget the diode, would serve no purpose except adding complexity.

It’s not really a decision to get rid of the ballast resistor, you have to. The Sniper wants full voltage in crank and run - can’t do that with the ballast resistor in place and functioning.

Way back in the Jurassic period, the ballast resistor was designed/used to prevent full-fielding the coil during crank. This prolonged service life of the ignition system by not burning points.

What you’re doing when you “tie IGN 1 and IGN 2 together” is bridging the ignition switch crank and run positions to eliminate the circuit break between the two points. The car won’t even start or run with a Sniper (or MSD for that matter) unless the start circuits are tied together.

Sniper is digital, don’t need to worry about saving your oil-filled canister coil or points for 100k miles. It’s out of warranty by now anyway.

What ignition are you using? If you’re trying to get away with a regular distributor and orange box forget it - you’re defeating half of the Sniper’s benefit which is allowing the ECU to control timing.

If you’re willing to go EFI, ditch the rest of the ancient technology and give the thing what it needs.
 
^^Except most all Bosch relays already have diodes internally^^

Here's a question, tho, Dave........if a relay has no internal diode, and you add an external one, can a diode in series with a resistor increase release delay time?
Resistor adds loss, decrease time delay. Diode provides path for stored coil current to circulate, hence holding relay closed longer. A relay hold current is typically 1/4 normal operating current.

A scope can be used to capture hold time, by triggering key switch falling signal, and viewing relay output.
 
I’ve decided to eliminate the 2 prong ballast tie them together and tie into that for my power to the sniper.
I know I answered here already but when the new reply alert came up I re-read your initial post and missed the part about the main power and ground - do not do this. Will it work? Mostly. Will you have problems because of it? Yes. Perhaps you missed it in the instructions - it only says to connect the Sniper main power and ground directly to the battery like 732 times.

It seems like you're making this harder than it has to be. Make the connections as described in the instructions. Again - forget about a diode in the start circuit and just tie them together like they want it. You will be much better off in the end if you follow their instructions. 99% of all their 'failures' and subsequent returns are due to "operator error" and not the parts themselves. Don't be that guy!

If you ever have to call Holley tech support, the first question they will ask you is if the Sniper main power and ground are connected directly to the battery. Should you follow through with your plan to use the start circuit for you main power, your answer would be 'no.' Their answer would then be, "sorry, we can't/won't help you until you connect the main power and ground directly to the battery."

The main reason they want the ECU power and ground connected directly to the battery is because the Sniper is susceptible to RFI. RFI can and will wreak havoc on it. The main ECU 12V source has to be 'clean', meaning there is nothing else pulling power from your connection point - the battery is basically the only point in your electrical system where that is 100% true. Some will argue this but anywhere else (including the starting system) is not going to be 'clean', at least for the purposes of getting the Sniper running properly. Any suspect wiring or connections will only increase the chances of RFI happening. It's not always obvious either until you start getting into data logs trying to figure out an issue.

I helped a neighbor install a Sniper on his Brand X machine. His wiring was a mess, the battery cable was attached to the lug by one single strand of copper. Before he even started, I urged him to re-wire the car or at least the parts that were related to the Sniper. He did not want to hear that. His ego got in the way because he'd been around the block and knew better. Against my advice, he installed the thing on his own and guess what? The car would not start. After several attempts to figure it out including hours on the phone with Holley, he was ready to throw the Sniper through the window. Eventually he relented and re-did the wiring like Holley said and wouldn't you know it? It fired right up. 100% true story, no exaggerations.

Don't mean to come across like an ***, just trying to save you or anyone else reading this endless headaches. Good luck.
 
You need to CHECK it. Get your meter and get to work. Does this sound harsh? NO. It means it is what you have to do. Forget diodes

Clip the meter to the battery. Note the reading. Turn key to "run" Note the reading. Ground the coil wire so it will not fire. Twist to start and crank, and note the reading

Now clip the meter to the coil + wire. Take the same readings, key in "run" note reading and key in "start" and cranking note the reading.

There should not be more than say, .3V between the battery readings and the coil wire readings.

The battery should be 12.6 fully charged. The battery should not sag below 10.5 minimum when cranking.
Thanks I took care of everything. Ready to fire up soon
 
I just installed the Sniper 4150 and Hyperspark Ignition in my 69 Barracuda with 440. All went well except for the dreaded 12volt switched source that is required. I have 6 fuses in the fuse box and none that have 12 volts while on and cranking, and off when the key is off. If I use my third arm and hold the pink wire on a 12volt source and turn the key, the engine fires right up. When I turn the key off, the fuel pump keeps running. So...i know it starts and runs. There was a thousand ideas and recommendations out there on the old interweb on what to do for a 12 volt switched source in a Mopar, so i just called Holley and they said get a 4 pin, 30 amp Relay and a diode. Pink wire to 87, Ground wire to 85, Battery(+) with fuse to 30, Starter solenoid to 86. He stated that a diode should go in between the solenoid and relay to prevent back interference. I'm going to do exactly that tonight and see what happens. I'll be sure to provide an update on how it all works out.
 
I just installed the Sniper 4150 and Hyperspark Ignition in my 69 Barracuda with 440. All went well except for the dreaded 12volt switched source that is required. I have 6 fuses in the fuse box and none that have 12 volts while on and cranking, and off when the key is off. If I use my third arm and hold the pink wire on a 12volt source and turn the key, the engine fires right up. When I turn the key off, the fuel pump keeps running. So...i know it starts and runs. There was a thousand ideas and recommendations out there on the old interweb on what to do for a 12 volt switched source in a Mopar, so i just called Holley and they said get a 4 pin, 30 amp Relay and a diode. Pink wire to 87, Ground wire to 85, Battery(+) with fuse to 30, Starter solenoid to 86. He stated that a diode should go in between the solenoid and relay to prevent back interference. I'm going to do exactly that tonight and see what happens. I'll be sure to provide an update on how it all works out.

I'd trigger the relay from the ignition circuit which powers the coil. That's exactly how I did it in my Dart and it works perfect. I later removed the ballast resistor and added a jumper wire to my mini-harness. No change in function, works perfect.
 
Just tie IGN 1 and IGN 2 together. The relay works but adds complexity when none is needed.
 
Just tie IGN 1 and IGN 2 together. The relay works but adds complexity when none is needed.
The reason a relay is beneficial or in other words NEEDED (in place of some other solution) is that harness voltage drop, rampant in these old girls, causes the VR to OVERvoltage, since it is getting UNDERvoltage.

The relay supplies full battery to the ignition "run" wire, the alternator field, and the VR
 
Just tie IGN 1 and IGN 2 together. The relay works but adds complexity when none is needed.

A relay is hardly complex.
Depending on how much current the effect needs to pull across that wire, the voltage drop could be enough to cause significant problems and especially when cranking.
Having a relay triggered by ign1/2 can have many uses and prevent unwanted overloads or drops.
 
Well, I did as Holley said and grabbed a 5 pin relay with diode built in. I wired it as they said but of course coming from the starter solenoid the screen and fuel pump turned on but cut out immediately during cranking and wouldn't start. I saw another post on a different thread where one said to simply tie your pink wire to your old +coil wire. I did this and it worked in both run and start position. So....I removed the relay and went this route to get it started and initial timing set. Tonight i'll take it for a drive and let the computer learn.
What i'm wondering now is, should I hook that coil+ wire into the relay so that the system gets the best/cleanest voltage? If so, is it just a matter of wiring it as shown here in the picture? My apologies as i am terrible with wiring and struggle to understand relays, especially with a diode in it.

Relay Pic.JPG
 
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