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Discussion Starter #1
stock 2v with the 8psi vortech kit (non intercooled) vortech supplied tune. I installed my kit exactly the way vortech suggested in the instructions. The car knocks with 93 even with octane booster. It seems to knock more under long WOT pulls. I'm assuming this has to do with heat building up in the charge pipe. Vortech suggests the stock spark plugs (copper) and stock plug gap. My question is should I try colder plugs or less plug gap or both. I gapped the plugs to 0.040". I've never really been clear of the effect plug gap has on pinging. Thanks for any help guys!
 

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Yes, a step colder plugs should be used. I think I used .034 gap on my 4v. The most important thing is that you get a custom tune.
 

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Use a NGK TR-6 plug, gapped at .028-.030"

Data log your timing, and make sure it's not going over 14* @ WOT.

I ran my 99 with 12psi, 93 octane, 14* of timing up top. Non-intercooled. It wouldn't ping/knock no matter how hot it got.
 

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stock 2v with the 8psi vortech kit (non intercooled) vortech supplied tune. I installed my kit exactly the way vortech suggested in the instructions. The car knocks with 93 even with octane booster. It seems to knock more under long WOT pulls. I'm assuming this has to do with heat building up in the charge pipe. Vortech suggests the stock spark plugs (copper) and stock plug gap. My question is should I try colder plugs or less plug gap or both. I gapped the plugs to 0.040". I've never really been clear of the effect plug gap has on pinging. Thanks for any help guys!
The other two guys have it nailed: check your timing and/or get a custom tune. BTW, I'd be nervous about running even just 8#s on a stock internal 2V without an intercooler...

Plug gap has nothing to do with detonation. The amount of voltage required to ionize the gap between the plug electrodes to establish a spark depends in large part on the amount of air between the electrodes. Air is a decent insulator and more air is a "decenter" insulator. More air, in the form of pressurization from a blower, increases the voltage required to jump the gap. Sometimes this increase is larger than what the coil or coilpacks can generate and the result is a cycle with no spark (i.e. a misfire.) You can help address this by closing down the gap. By doing this you reduce the voltage requirement and have a better chance at establishing an arc. Keep in mind that as you reduce the gap you also reduce the amount of mixture between the electrodes that will be exposed to the arc. If you go too far you may get a spark but no fire due to this and get back into a misfire situation again.

Empirical evidence suggests a gap in the low 30s (e.g. 0.032") works pretty well for factory COPs with blowers. If you sub in some "higher voltage" coils you might be able to open the gap up some more.

But yeah, get the car to a tuner and make sure they know their stuff and your combo to get a safe tune in there.
 

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Discussion Starter #5
You guys are great. Thanks a bunch!
 

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Discussion Starter #6
I have a follow up question. Do i want the s type or x type. I found the tr6 plugs, but there seems to be two models. Also, does anyone else know of a good PI head spark plug that is colder than stock? Thanks
 

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Discussion Starter #7
?
 

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NGK TR6 Part # 4177. One step colder than stock.
 

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Discussion Starter #9
So i went from stock temp at .040 to one step colder NGK plugs gapped at .035 Before, the car ran great but knocked under heavy boost. Now it is hard to start and "bucks" under boost. It feels like it's missing bad. Keep in mind that it doesn't start missing until under boost. I'm thinking that I'll pull the ngk plugs out and gap them to .040 like the original plugs were. I think maybe the tune goes rich under heavy boost. Maybe this requires me to run a big gap to have a big enough ignition source.
Any thoughts?
 

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With a big pump you need to keep over 1/2 a tank of gas in the car all the time or it WILL detonate! I see guys do this all the time at the track. They run the car on E and have the boost retard on -3 and it still detonates. Then they add gas and can turn the retard to -1.
 

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Discussion Starter #11
hmmm...... That's something to think about. I can't imagine how that would relate to anything, but it's interesting. Maybe the baffling in the stock tank won't keep the gas where it needs to be during hard acceleration so you have to fill it up.
 

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So i went from stock temp at .040 to one step colder NGK plugs gapped at .035 Before, the car ran great but knocked under heavy boost. Now it is hard to start and "bucks" under boost. It feels like it's missing bad. Keep in mind that it doesn't start missing until under boost. I'm thinking that I'll pull the ngk plugs out and gap them to .040 like the original plugs were. I think maybe the tune goes rich under heavy boost. Maybe this requires me to run a big gap to have a big enough ignition source.
Any thoughts?
The idea of running a tighter gap is to keep the air and fuel mixture from "drowning" the spark.... Running a larger gap will only make the blow out worse. I would absolutely not run the car in boost until u have it custom tuned!!
 

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As far as fuel level is concerned I an run mine until it's empty and have absolutely no trouble. When the needle physically touches the "E" line it will hesitate if I launch it hard but no detonation.

Sounds to me like that Vortech supplied tune is junk. They usually get it pretty close from what I've seen but nothing beats a good ole dyno tune.

I will say that it sounds like something is starving the motor of fuel during high boost. This leads me to believe that you are pegging your MAF. It is directly responsible for telling the computer how much fuel to squirt out of the injectors. Once it pegs, the computer will have no idea that a ton more air is actually entering the motor and thus won't compensate with additional fuel.

What kind of MAF do you have in there now? What size injectors came in the kit and what size fuel pump? I installed a 99-04 kit for a buddy a couple years back and what I had Vortech do is just send me a blank SCT chip that we had burned at a dyno shop. Car made 400hp to the tires at 11psi and was a blast!
 

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Discussion Starter #15
99fiveoh, the vortech kit is designed to use the factory maf. With that said, I believe the vortech tune just takes an educated guess after it hits 5 volts. I know that this is a horrible way to do it, but I'm sure they keep it fairly rich for that reason. I haven't noticed a difference in performance related to the tank level either. I don't really think its the fuel level either, but I do appreciate the ideas from everyone.
 
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