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Discussion Starter #1
Finally got the sniper wired & plumbed in the 351c.
went through the basic setup procedure, timing, 12 & 34 idle, ect.
fired up & sounded awesome, took it out for some street driving & started missing a beat, took it on the motorway/freeway anything past 40-45mph the engine would just die then pick up, foot down gently back up to 40-45mph would just die again till I took my foot of the gas peddle.

can anyone help me out on all the other settings that might need adjusting cuz I ain’t got a clue, or share the full list what might work.
thanks Mark.
 

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Discussion Starter #3
I have the Holley 12-305 in tank fuel module fitted.
 

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I think he's asking if you have a fuel gauge or can read the pressure off the handheld unit. I.e. 58 lbs.
Hand held does not read fuel pressure. He has to install a pressure gauge in the fuel line and check the pressure at idle and higher rpms. I installed mine on the inlet fitting that attaches to the Sniper.
 

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Hand held does not read fuel pressure. He has to install a pressure gauge in the fuel line and check the pressure at idle and higher rpms. I installed mine on the inlet fitting that attaches to the Sniper.
Thanks I wasn't sure if the hand held read that parameter or not.
 

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Discussion Starter #7
Thanks guys,
I’ve took a back seat & re-accessed how I’ve set this kit up.
A couple of mistakes which I think I’ve made.

The 2 pink & the small red wire are all tied in together & join the red wire the powered the old MSD box, I’ve just realised the pink coming out of the sniper harness should go to hot while crank ignition switch ?? & the remaining pink & small red wire are fine connected to power that went to the MSD box. ??.

I have the full Hyperspark system fitted.

ignition coil SNE-556-152,
I used an old coil wire for a canister coil, so this has the wrong end for my new coil, which is quite loose.

Do you think these are causing the problems I’m having.

Cant get to the car for a few days but will get these sorted. Thanks Mark.
 

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Read this:


Andrew
 

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Discussion Starter #9
Well, I’ve sorted out the problems stated above.

The car now sounds & drives better then ever.

question now is about timing, initial is at 12, wot is at 36, not quite sure about Cruise timing, should this be 2-3 degrees Higher or lower then wot.
Also static timing, does this come into play with the Hyperspark full ignition system.
Thanks Mark.
 

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You can generally run a few more degrees in the cruising and decal areas, compared to the WOT settings.

Andrew
 

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Static timing is usually set in the 15 to 20 degree range, depends on the engine. The Sniper will be controlling the timing so it will be based on a multitude of factors. One thing you need to sync the timing and set the inductive delay. The timing can drift 0-30 degrees just due to the width of the rotor tip. There's a procedure there I can share with you if you'd like..
The Sniper on my ride was off 25 degrees, I corrected it by setting the inductive delay...
 

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Discussion Starter #12
Static timing is usually set in the 15 to 20 degree range, depends on the engine. The Sniper will be controlling the timing so it will be based on a multitude of factors. One thing you need to sync the timing and set the inductive delay. The timing can drift 0-30 degrees just due to the width of the rotor tip. There's a procedure there I can share with you if you'd like..
The Sniper on my ride was off 25 degrees, I corrected it by setting the inductive delay...
I need as much information as possible , I would really appreciate anything that you can share that will make improvements.
1 thing I have noticed is the MPG has dropped from 12-15mpg to around 5-7mpg. Any ideas how I could improve this.
cheers Mark.
 

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Ok this is a little lengthy on HOW TO SET TIMING. First, make sure the timing is in SYNC. This makes sure the timing in the tune, is the same as timing shown on a timing light. You will go into the handheld or laptop, in the “Tuning” menu, under “Ignition”, and find “Static timing”. What this does, is command the ECU to HOLD a specific timing value, in order for you to check the timing with a light. Otherwise, the timing will be moving around at idle, and you can’t use a light. This is called idle spark, its faster to control RPM with timing changes than airflow changes from the IAC. Therefore the timing will be jumping 10-15* at idle, that’s normal. You can turn this function off, but idle quality will suffer. So, in order to check the timing without it jumping around, you have to use the STATIC TIMING .The value you choose, has NOTHING to do with total timing, or initial timing like with a mechanical distributor. This just tells the computer to HOLD a specific value. I use 20 degrees. You can use any number that your balancer has a stripe on. You will type in “20” and hit “SET”. THAT SCREEN MUST STAY UP*. The computer is now holding 20* for you, until you either hit “CLEAR”, or leave that page, then timing reverts to whatever is loaded in the timing options in the tune at that RPM. Now, while the computer is holding 20, you will put a timing light on the engine, and check it, and see what it’s showing. If it is not at 20, loosen and twist the distributor until it is at 20. Then lock it down. Your timing is now in SYNC. When the computer asks for 20, you made sure it’s getting 20.
Now part 2, inductive delay..Go into the “Tuning” menu, “Ignition”, and set static timing again. I prefer to use 20* because most engines will idle fine at 20* and be able to rev past 3-4k rpms. You can use any number your engine will idle and rev clean at. Now, while the static timing is holding 20*, watch the TIMING LIGHT, and make sure that when you rev the engine up past 3-4k rpms, the timing does NOT drift advanced past 20, or retarded below 20. If it HOLDS 20, you are done. If it drifted, you need to adjust the INDUCTIVE DELAY value.
Close the static timing page and go to the ”Inductive delay” setting. It’s in the “Ignition/Spark” menu, in the “Tuning” menus. Adjust it as follows: If the timing retarded, add 20au, if it advanced, subtract 20au. Then run the test again, *Don’t forget to set and hold “static” timing first, otherwise the timing will jump around as you rev it Once it is holding 20 degrees again, check 20* at idle with the timing light,. Then rev to 3k-4K RPM or more, and see if it drifted or not. If yes, add/subtract another 20 milliseconds to the inductive delay. Eventually, you will get the timing perfect, and the timing light will maintain rock steady at idle, and past 3-4k rpm. YOU ARE DONE!

The fact it's getting such terrible mileage suggests a fuel pressure issue, have you verified fuel pressure yet? That is a must...My experience with the Snipers so far is that you cannot have enough grounds. My 57 has 5 grounds, for whatever reason the Sniper is very sensitive to RFI. Good grounds, good wiring technique, crimp and solder everything.

I would consider, up to you..getting in touch with Mad Science Motorsports. They guy is very sharp with the Holley EFI products and goes to great lengths to get your car dialed in. For $300, and lifetime tunes and support it's well worth it.

Again check fuel pressure, set the IAC and get the timing set correctly, see where you're at after that is all done..

Let me know if I can help further..
 

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Discussion Starter #14
Thanks, that’s a great & very helpful description,
What’s the procedure of checking the fuel pressure, is this through the handheld, or a fuel pressure gauge, & what should it be reading ?

Just for future reference, how do I get in touch with mad science motorsports.
Thanks again, Mark.
 

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Discussion Starter #16
Ok, according to the handheld, on idle it’s 6-7psi & increases as you accelerate Between 6-7 to 50-58 psi.
so does this sound like the pressure is working fine.
 

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The only way to check fuel pressure on a Sniper (and ALL fuel injection systems that do not have a fuel pressure transducer) is with a fuel pressure gauge. Whatever you think you are seeing, it is not displaying fuel actual fuel pressure. It is the fuel pressure the system expects. Many Snipers seem to get a clogged or defective regulator. The result is fuel pressure near 100 PSI. The handheld only shows what fuel pressure is programmed. As far as showing 6 to 7 PSI at idle, I don't see how this is possible. Fuel pressure should be consistently near 58.5 PSI at all times.

Earls AT100192ERL Earls Fuel Pressure Gauge Adapter
 

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Discussion Starter #20
The only way to check fuel pressure on a Sniper (and ALL fuel injection systems that do not have a fuel pressure transducer) is with a fuel pressure gauge. Whatever you think you are seeing, it is not displaying fuel actual fuel pressure. It is the fuel pressure the system expects. Many Snipers seem to get a clogged or defective regulator. The result is fuel pressure near 100 PSI. The handheld only shows what fuel pressure is programmed. As far as showing 6 to 7 PSI at idle, I don't see how this is possible. Fuel pressure should be consistently near 58.5 PSI at all times.

Earls AT100192ERL Earls Fuel Pressure Gauge Adapter
Thanks for the link, I’m still new to this fuel injection, still got a lot of learning to do, & I appreciate all your comments.
thanks Mark.
 
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