Engine run-on with sniper efi

Slowpoke86

Not-quite-so-new-guy
Jul 28, 2019
18
13
South Florida
I've recently installed a Sniper QuadraJet and HyperSpark on my '86 Buick Regal. It's a bone stock 307 Oldsmobile engine. Two days ago I did the first startup and it was good, first drive was nice and easy but ran a little warm, but that's for another post. Fast forward to this morning, I went to move the car and when I shut it off and took the key out it just stayed running, and running good at that. But I pulled the fuel relay and let it die. I've done some research and I believe it would be backfeed. My Sniper, distributor and HyperSpark box triggers are sharing the same relay ran off the OEM distributor (+12V, 12 AWG, pink wire). I'm going to put the Sniper on its own relay, and the distributor & HyperSpark box together on their own relay from what I've found on Holley that is most likely the issue. With all that being said, would it be OK to share the switched +12V between the two relays?
 

64nailhead

Goat Herder
Supporting Member
Dec 1, 2014
2,909
113
Upstate NY
Can you say what part number you have and what is a Hyperspark box?
 

Slowpoke86

Not-quite-so-new-guy
Thread starter
Jul 28, 2019
18
13
South Florida
The sniper is PART# 550-869 the hyperspark is the ignition and distributor that is controlled by the sniper system.
I know power wise it will work because I have them all to one relay now and it all runs fine but the sniper trigger needs to be put to its own power. If I put them on separate relays could the one 12v switch be used for both relays.
 
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64nailhead

Goat Herder
Supporting Member
Dec 1, 2014
2,909
113
Upstate NY
Help me out here, your HyperSaprk is a Holley part the Sniper is designed to work with? It's a single coil attached to a dizzy with a plug for your Holley? Kinda like the way a factory GM 8 pin HEI works on TBI or TPI unit?

Can you describe exactly where you have grounds and and how you hooked up the Holley 12v, switch 12v, ground and crank signal?
 

64nailhead

Goat Herder
Supporting Member
Dec 1, 2014
2,909
113
Upstate NY
We were typing at the same time. The Holley 12v and ground (a large gauge black and red wire in it's own loom) need to be directly at the battery - no relay.
 

Slowpoke86

Not-quite-so-new-guy
Thread starter
Jul 28, 2019
18
13
South Florida
Help me out here, your HyperSaprk is a Holley part the Sniper is designed to work with? It's a single coil attached to a dizzy with a plug for your Holley? Kinda like the way a factory GM 8 pin HEI works on TBI or TPI unit?

Can you describe exactly where you have grounds and and how you hooked up the Holley 12v, switch 12v, ground and crank signal?
It's all plug and play together. Yes it's like the hei ccc system for the most part.Its a small cap distributor with external holley coil and hyperspark ignition box. The main powers and grounds are for the sniper unit and the ignition box to the battery + and - as directed by holley instructions. The distributor plugs directly into the sniper and there is a points wire that goes to the hyperspark box and the hyperspark plugs directly into the coil. That leaves 3 wires left Sniper trigger , distributor trigger and hyperspark trigger. I hooked those three triggers up to a relay but it's back feeding the sniper so when I turn the key off in the car the car just stays running and does not shut the sniper off.
 

64nailhead

Goat Herder
Supporting Member
Dec 1, 2014
2,909
113
Upstate NY
What do you have for grounds? Without lecturing you should have an engine to frame and engine to body ground, and also a battery to frame or body ground.

There is no such thing as 'too many grounds'.

EDIT : I've found it easiest to use the factory fuse panel for 12v power supply for relay triggers.
 

Slowpoke86

Not-quite-so-new-guy
Thread starter
Jul 28, 2019
18
13
South Florida
What do you have for grounds? Without lecturing you should have an engine to frame and engine to body ground, and also a battery to frame or body ground.

There is no such thing as 'too many grounds'.

EDIT : I've found it easiest to use the factory fuse panel for 12v power supply for relay triggers.
All the stock grounds are in and brand new including the braided body to block.
 
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