Where can I find a constant 12v when the key is in the run position and when cranking the car. I’m running Holley Sniper 2 with hyperspark in my car. I tried connecting to the pink (IGN) wire from the fuse box but that drops to 9-10v when cranking the car.

 

IGN tab in the fuse box should be 12 vdc when in ON(run) and when in START(cranking). The drop in voltage is more than likely due to that draw by the DC Series wound Starter Motor..... it's a bid dadgum DC load.

When i needed 12 VDC in Start and Run I ran a lead from the IGN terminal to a Relay. I then powered the load side of the Relay from the Horn Relay Bus terminal. I power my EZ-EFI, MSD distributor, and other loads requiring power in START & ON from that relay supply. You can fuses to the individual loads as you desire.

 

There is no 12V available during cranking. Put a volt meter on the battery during cranking. The voltage will drop to 9-10 volts due to the current draw of the starter. A mini- starter might reduce that a small amount but it still takes power to start the engine.

 

ok what would you suggest I do to power the sniper 2 with hyperspark? I already have a mini starter installed in the car. I would really like to fix the issues I’ve been having due to the drop in voltage

 

for the most part, 'mini starters' are produced in two 'flavors'
Nowadays, most all have an internal planetary gear reduction (or similar), but flavor 1 still has those old wound electromagnetic field coils w/ pole shoes.
While flavor 2 supplanted current-hogging & heavy field coils with permanent magnets.
GM and most other car-truck makers advanced to flavor 2 by about 30+ years ago: Permanent Magnet + Gear Reduction aka PMGR (most PMGR weigh less than half what OE C3 starter does, produces more work while requiring less power, and are proven more reliable). Starter choice opinions are varied.

 

Have you tried a new battery?

I run 75 series batteries, but the 78 series also fits, and has a bit more capacity.

Check your battery cable connections, including at the starter, and especially at the ground connection on the chassis.

 

There is a Sticky above that is all about sniper installation and tuning. Perhaps give it a read.

 

If I ever go this route, I was thinking of doing what my wife’s Jeep Compass has. I would install a small, lawnmower/atv style battery and have it charging off a 12v source, but run my constant hot/low amperage electronics off the smaller battery. Would this type of setup work?

With theses newer cars and that constant start/stop of the engine in traffic, it solves the problem for the hi/low voltage from the starter.

 

How exactly did you connect to the ignition wire? Did you run a new wire from the spare ignition spade in the fuse box or something else?

 

yes I ran a new wire to the spare ignition spade in the fuse box

 

No I haven’t tired a new battery… my battery is 5 or so years old. I just replaced the main battery ground should I also replace the positive cable to the starter?

 

Don't throw parts at it until you test it, but I'd get that battery tested. My 5 yo battery tested at ~50 CCA (vs the rated 650), so it became a $20- core for the replacement. If the cable is good, it's good, but a loose connection can cause a voltage drop.

As @4-vettes pointed out, I bet Holley requires a (relay-switched) clean 12V source tied directly to the battery. Perhaps they even provide the relay.

 

I know with the resistor wire in place, which you have bypassed to the Sniper, the second 12V wire from the starter solenoid to the coil provides full 12V during start up.

I don't know if it would help any to connect the Sniper to that wire in addition to the ignition wire you ran from the fuse box but maybe.

Also, a 5-year-old battery is pretty much due to be replaced. Might as well put a new one in and see if that helps.

 

^^^THIS^^^
First thing, have a local shop (best is an 'Auto Electric Shop') not simply test it, but specifically 'Load Test' battery with their 'carbon-pile' battery tester. Absolutely nothing else is better than 'carbon-pile' Load Test to reveal true nature of battery condition. Either confirm or deny battery is healthy; anything like mediocre will cause issues and will let you down. An Auto Electric Shop is one that routinely rebuilds alternators, generators and starters on a daily basis.

 

I ran a new circuit breaker and wiring to power the Holley EFI equipment and it is connected to the battery directly as per the instructions. For the 12 volt power I found the one terminal on the fuse-block that supplies full battery voltage during cranking. This past fall I noticed that I had my 12 volt "sense" wire was attached to the resistor wire which dropped the voltage a bit but not enough to shut down the engine or ignition. I fixed that wire and it now has an solid 12 volts on it and the engine seems happy.

The Sniper systems seem to not like "electrical noise" so you need to avoid any wire that is connected to anything high tension ignition related. I even shielded and grounded the shield for the wires that connect and fire my ignition coil to keep them from making issues for me. My ignition box and accessories are on the passengers inner fender well and away from the noise generating high powered ignition wires and ignition coil.

After many issues with coils failing while mounted on the engine I now have a ignition coil mounted on the fire-wall of the C3. I ran a ground wire to the Ignition coil to be sure it works its best. The new coil is a newer Holley "E-style" ignition coil from Holley and I hope it last longer than the previous coils have.

The five year old battery is in need of being tested just because of the "age". If you only use it once in a while you might consider an AGM battery. COSTCO sells INTERSTATE Batteries at great discount. I personally use a deep cycle battery to allow my system to have the fans run after shutdown.

IF you do choose a new starter be sure to buy a Gear Reduction type starter that spins the engine faster that the factory ones did. The gear reduction spins my 12.5-1 compression with no problem even when HOT. It also uses less current to start the engine which lightens the load on the battery letting it last longer.

 

If your Sniper EFI indicated voltage is never going above 12 vdc then you have a different problem. I would also put a voltmeter on the battery and monitor that during START and RUN. If it goes NOT go the generic 14 vdc during RUN then you have a different issue. Your alternator should maintain running volts at about 13.7 to 14+ volts.

 

I don't personally run the Holley system. But I've worked on them and countless other EFI systems. I personally run a FiTech based system.
None the less, a voltage drop to 9 or 10 volts should not be a issue in any way. These systems shouldn't drop out until the voltage reaches about 7 volts.
I run a dedicated power wire off the battery, through a independent strip fuse, then out the battery box and along side the positive battery cable to the starter area. Then up the firewall with the stater harness. Then to a relay mounted on the firewall. Then to my EFI ECU. The ground wire runs with it. Also a dedicated ground straight to the battery. These wires are 6G. Can't over kill clean power and clean ground.
And yes my original factory starter pulls the power down a tad. However, absolutely no issues.
Just wire it correctly, your over thinking this.

 

It is possible that Holley is only looking for a circuit that will carry system voltage for On, Start and Run. This would be considered a 12v. circuit even though system voltage may vary from approximately 10 to 14 volts. ECM, ABS, and Air Bag Modules, for example, will function normally if voltage drops to as low as 8.0v. during crank or when system voltage maintenance malfunctions. In some cases, such as an Air Bag Module, an internal capacitor will supply enough voltage, for a certain period of time, to activate the air bags when power is off or interrupted.. Holley indicates reliable operation from 7-28 volts, but operates best with a stable 12-14 volts. The Hyperspark coil receives impulses from the module, not the "12v." source.

 

This likely would work...just need to diode isolate the second battery so it does not see the starter load. Still charges when its voltage is low from the generator and primary battery circuit. There are products available that do this for running dual battery setups.

 

GM at one time came out with the stop and start engines (4 cyls) to save fuel at stop lights or long idle situations. The alternator was used to start the engine. This was all automatic and not well liked by customers. This also used a small auxiliary battery located in the trunk and was operated by a module. There was a lot of issues with the auxiliary battery, mostly weak or incapable of being charged.

It may be possible to build a separate electrical system for just the ignition system with a separate charging system to establish a constant 12-14 volts. Or build a voltage filter/scrubber to clean your system voltage to provide a stable 12-14 volts with capacitors to fill in the valleys during heavy load conditions.

In reading the limited information Holley provides for the Hyperspark system, it does operate at 7 volts. To me that will provide spark during crank. During "Run" Holley says it operates best with a steady 12-14 system volts. The info also states that the module provides voltage to the coil. To me that means system voltage is not directly fed to the coil. I suspect that system voltage is scrubbed to provide an even voltage (say 12.5 volts) with a tight +/- control. Rather than assume, call Holley and talk to Tech about your voltage concerns during Start, and what is needed during "Run".

Or have I misunderstood the entire thread. .