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Coils overheating, sniper EFi system

skingjack

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Any thoughts on what might be causing coils to continually overheat causing the efi system to shut down & consequently the engine dying while moving.

Circumstances are just like this posted elsewhere by another individual: "I am overheating and burning out coils, I’ve went through 8 to date. The first time I noticed something was not right is when I drove the car continuously for a period of 2 or more hours, which is when the engine just died on the HWY. I felt the coil and it was way too hot to touch so I waited on the side of the hwy for about 30 minutes until it cooled down and the engine started and ran long enough for me to get to Lordco parts to buy another coil. I replaced the coil and the engine started and ran perfectly, until about an hour of driving when the same thing happened and I realized that I was dealing with not just a defective coil issue."

EFI is wired per directions and vehicle is grounded - battery to head, heads to chassis etc.
Open to any feedback.

Ian

Background info: 69 RR, 493 big block stroker, A518 trans, MSD 8222 coil(s), MSD Ready to Run distributor, Taylor wires, Tanks Inc. EFI tank, Aeromotive Stealth 340 in tank pump.
 
What readings do you get from the oxygen sensors? Coils tend to run hot due to lean mixtures, high resistance in the plug wires and excessive dwell time... How is the MSD/Sniper connected? I've read that you eliminate the RTR circuitry & just feed the output of the pickup to the Sniper... I've also seen where that causes excessive RF noise which could lead to other components failing... Might want to go to the Holley Dual Sync like most guys do..
 
Replacing 8 coils is ridiculous. Coils do get hot, the problem is not the coil. Either the ignition parts are not properly matched or there is resistance somewhere. Check the wiring from the ignition switch to the spark plugs, make sure it’s all in good order with no half-assed connections. Hopefully you ditched the ballast resistor, not sure it’s even possible to run a Sniper with it. Make sure the plugs are the correct heat range and are properly gapped.

Holley recommends their Sniper coil which is an “E” type, same as a Ford TFI coil used on 5.0 Mustangs. EFI needs a really good spark to work optimally. The MSD 8222 is an old school canister coil, I wouldn’t use that, especially if it’s mounted far away from the distributor but that’s just me.

I know lots of people skip the hyperspark distributor and ignition box and run garden variety components but methinks it’s best to match the system with the parts the Sniper was designed to use.
 
Not familiar with the Sniper, but look to see if you have a Dwell setting you can adjust. You are grounding (triggering) the coil too long. That's why it's hot. You should try to adjust the Dwell to the least amount before you detect misfire, then add about 0.5 ms. I'm running a Jeg's special at 2.1 ms Dwell. Then, I've been told MSD (and maybe Sniper, don't know) control Dwell via percentage of period; they keep the coil fired typically around 15% of the cylinder-to-cylinder time. That works well at >3500 RPM, but triggers way too long at idle.

Either way, see if you can't shorten how long your coil fires.
 
Not familiar with the Sniper, but look to see if you have a Dwell setting you can adjust. You are grounding (triggering) the coil too long. That's why it's hot. You should try to adjust the Dwell to the least amount before you detect misfire, then add about 0.5 ms. I'm running a Jeg's special at 2.1 ms Dwell. Then, I've been told MSD (and maybe Sniper, don't know) control Dwell via percentage of period; they keep the coil fired typically around 15% of the cylinder-to-cylinder time. That works well at >3500 RPM, but triggers way too long at idle.

Either way, see if you can't shorten how long your coil fires.

I agree with this. My son runs the Sniper EFI with the Holley dual sync dist and uses an MSD box with the MSD coil. Course he runs one coil but with your setup I would guess the coils are all fed 12 volts on the primary winding so as stated the dwell will be controlled by the controller you use as to how long it grounds the primary winding. What can make the coil run hot is to much dwell (saturation) time for that type of coil. Resistance in the primary wires would only cause a lower voltage to the primary windings and a weaker spark which should not overheat the coils. I know on my sons Sniper it has a place where you can adjust the dwell as "mpgmike" said. I would talk with the Holley tech and tell them which coils you run and see if they can also help some. I know sometimes you can get some very good tech at their tech line and other times some not so good but most have to be pretty good to work at the tech line center.
A friend had a Fi-Tech EFI that I was working on as it would start but not keep running. I narrowed it down to the Fi-Tech controller bad so I called their tech line even though everyone said its a waste of time that their techs dont know much. Well this guy knew his **** and asked me if I checked everything I had and agreed with me the controller was the problem. So he sent me a compressed file to put in the controller and it fixed the car. So yes their are some very smart tech guys out there working for these companies. Never hurts to call and see if they can help also. Good luck , Ron
 
There's a setting for coils and if you pick the wrong one it burns them out. I've read about this a few times on LS engines (individual coils) with the Holley ECU. I'm guessing it's the same setting problem you're having. I'd check with EFISystemPro or Adam @ Mad Scientist Motorsports https://www.facebook.com/search/top?q=mad-science motorsports . He's remote tuning my '55 Chevy that has a Sniper.

This may be something with LS engines only but never know.
 
Sniper takes you through a setup wizard which has you choose the type of ignition components it’s talking to, kinda hard to skip it. Would also be pretty tough to choose the wrong components, the drop down list is clear.

The “dwell duty cycle” can be changed in the advanced ignition table in the handheld. Like stated already it’s usually 2.0 msec, or at least that’s what is used for the Hyperspark ignition.

Go on the Holley Forums and present your question there. You will probably be asked to upload a log file or a GCF (global config file). Might want to learn how to do make that happen and then understand what you’re looking at, it will be a tremendous diagnostic aid.
 
He said he's burnt out 8 coils so I'm guessing it's "coil on plug" setup. That's definitely not typical for the sniper install.
 
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No, he said in the first post he is using an MSD 8222 which is an old school canister coil.

But yeah, after the 2nd or 3rd one maybe you’d start to think something else might be the problem.
 
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