Holley Sniper on a little 3.0L Mercruiser
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Holley Sniper on a little 3.0L Mercruiser
I’m new and usually over on Iboats but 90% of Holley Sniper information seems to come from here.
im in the tail end of repowering my 1971 StarCraft Offshore V18. I put a complete 1986 Alpha Gen 1 3.0l in it. My wife wants it turn key like my little boat which has a 25HP EFI Suzuki.
I have ignored EFI in the past but am now considering it. Wife will allow the budget and wants it. I’m looking at the Sniper. A Hyperspark or Dual sync distributor isn’t available, but Delco EST is available. I know some use small cap HEI for Sniper, which the Delco EST almost is, but would I be able to phase the rotor and make it work?
I was thinking that if I had timing control, I could use the 2 step with the shift interrupter to drop the rpm down for the alpha to shift.
currently it has a Chinese carb as the original was missing part of choke linkage, and a points distributor. It idles good but needs bugs worked out. Any insight as to my plan? As to what the boat is. Just an 18’ tin bowrider, but someone in the past put a ton of work into
im in the tail end of repowering my 1971 StarCraft Offshore V18. I put a complete 1986 Alpha Gen 1 3.0l in it. My wife wants it turn key like my little boat which has a 25HP EFI Suzuki.
I have ignored EFI in the past but am now considering it. Wife will allow the budget and wants it. I’m looking at the Sniper. A Hyperspark or Dual sync distributor isn’t available, but Delco EST is available. I know some use small cap HEI for Sniper, which the Delco EST almost is, but would I be able to phase the rotor and make it work?
I was thinking that if I had timing control, I could use the 2 step with the shift interrupter to drop the rpm down for the alpha to shift.
currently it has a Chinese carb as the original was missing part of choke linkage, and a points distributor. It idles good but needs bugs worked out. Any insight as to my plan? As to what the boat is. Just an 18’ tin bowrider, but someone in the past put a ton of work into
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I figured it out. The Delco EST has a likely chance of being correctly phased out of the box as the small cap HEIs are and they are designed for ECU control. It makes sense for the EST distributors since the advance is controlled in the EST module, the rotor never turns, much the same
I just have to remove the module and fabricate a block off plate and pass a 2 wire connector through it to hook it up
I just have to remove the module and fabricate a block off plate and pass a 2 wire connector through it to hook it up
Last edited by Matt167; 09-22-2024 at 06:14 AM.
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Why block off plate ? Leave module to seal it. Just drill hole to pass pick up wires thru. I did this few times with for use of the daytona ign box for few v8 engines. I used small amt of epoxy on either side if hole (once wires passed thru) to seal hole/keep wires from moving/getting cut.
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Why block off plate ? Leave module to seal it. Just drill hole to pass pick up wires thru. I did this few times with for use of the daytona ign box for few v8 engines. I used small amt of epoxy on either side if hole (once wires passed thru) to seal hole/keep wires from moving/getting cut.
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I did not drill thru the module.
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I did have another thought on a hiccup. My boat runs 2 20 gallon tanks. I know the fuel return generally runs to the tank vent, which is fine except I have 2 tanks with a selector valve.
do I need to worry about over flowing one tank? Or just run one tank as a main tank and then switch to the other?
do I need to worry about over flowing one tank? Or just run one tank as a main tank and then switch to the other?
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I’ve pretty much decided this is probably the avenue I will go. I contacted Holley well before I created this thread and they finally got back to me. They wont offer support for any distributor that they don’t approve for timing control… but I know it’ll work
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just to put this out there but I have two cars at the shop now with snipers. one is a sniper 2 in a corvette and the other is a sniper stealth in a 70 cultass. neither work and are unreliable. the vette will work for a month or two and then either goes to "no data" and is inop or starts randomly dumping fuel in it as well as a few other oddities. the cutlass has all of 40 miles on it and worked good at first but now you get in and it goes to "no data" and you have to unhook the battery to reset it or the afr goes all over the place when ever it wants. the newest issue the other day was it ran for 4 seconds and died and would not restart. noticed that it was showing 1052 rpm while not running and would not let me do any thing with it as it said the engine was running. had to unhook battery to reset it. I have done everything that holley has suggested to no avail and the tech people seem to just read off a preprinted list of suggestions. right now both are about to be sent to the scrap bin as holley clearly has not figured out how to build an all in one unit. just my experience, your mileage may vary. personally I would buy a new carb and just run it.
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I’ll probably go back and forth multiple times lol. I’ll have it running on carburetor for next season anyway. I decided that I’m going to put in my spare 3.0L which is actually in much better shape and it has a good carb on it. I was looking into Affordable fuel injection as well being that system uses factory GM Rochester TBI parts, but their 3.0l system, they are cryptic as to what was used to tune it. No knock sensor and no O2 sensor could be very bad.
if the boat was a 4.3 prior, I’d stick in a 4.8L that I have laying around. But I don’t want to rework the entire back of the boat
if the boat was a 4.3 prior, I’d stick in a 4.8L that I have laying around. But I don’t want to rework the entire back of the boat