I saw a tech article that trimming the ground electrode on spark plugs to be even with the center electrode on the plug results in a stronger more consistant spark. Has anyone done anything like this? This is a tip for regular V8s and wonder if it would have any benefits on the 3.8Turbo.
trimming ground electrode on spark plugs
- Thread starter z1huggy
- Start date
R
Russ Merritt
Guest
Supposed to unshroud the spark, seen documents saying 5-8 HP on a small block chevy. You can buy plugs already like that but you can save the money with a dremel and cut off wheel. Probably never see the diff. with a turbo car. I do it, car runs great. (runs great no matter what plugs though, so who knows) All you can do is try it, what the hell.
I have been doing this on every car I had since my first one in 95. Works great for NA cars! I didn't notice a difference in my Ttype. Like Russ said though, a dremel and cut off wheel will let you know the difference.
PS
I have cut just a little off and about half of it off. It is A LOT harder to gap correctly with most of the electrode gone but the method I like best is, take a look at the plug from the top after you cut it. If you can see at least half of the center electrode, you should be fine.
PS
I have cut just a little off and about half of it off. It is A LOT harder to gap correctly with most of the electrode gone but the method I like best is, take a look at the plug from the top after you cut it. If you can see at least half of the center electrode, you should be fine.
Which Electrode?
Remember, on the "waste spark" system, three plugs fire center to shell, and three fire shell to center. Which would you trim? I think it has the potential to cause problems, and not much potential for helping. The AC plugs, and NGK, seem to have been well tested, and they work. The Buick engine is probably not going to see enough RPMs for ignition to be the same problem it is on chevy or a small block Ford.
Remember, on the "waste spark" system, three plugs fire center to shell, and three fire shell to center. Which would you trim? I think it has the potential to cause problems, and not much potential for helping. The AC plugs, and NGK, seem to have been well tested, and they work. The Buick engine is probably not going to see enough RPMs for ignition to be the same problem it is on chevy or a small block Ford.
R
Russ Merritt
Guest
As long as the gap remains consistant 30-35 ths on all plugs, everything will be the fine. The waste spark system always fires the EVENT plug center to ground, it's the other plug (thats conected to the same coil) that fires ground to center on that cyls. exhaust stroke (waste spark) to complete the loop! I run the MSD DIS 4 HO, and have gone as wide as 65 ths gap and ran fine. another thing (if you really want to get technical) use indexing washers to AIM the spark between the valves! Only if you have nothing else to do though, the gains are MINIMAL, maybe a little smoother running. I do both, (cut the electrodes & index plugs) just because I know it doesn't hurt to do, and only takes a couple of extra minutes.
blackbuick87
Senior Member
- Joined
- Mar 11, 2002
I wouldnt bother with it for the simple reason that the #6 plug is a pain in the ass
R
Russ Merritt
Guest
Only neg, they won't last as long. no big deal.
R
Russ Merritt
Guest
Exactly! don't run super cold plugs, unless your at the track. The car will run much nicer on the street with the SLIGHTLY warmer (24's-43's) If it wont run right with 24's,43's,104's (allum hds) find out why! (low boost 17-18#, 94 octane) don't know about alky cars, don't have it. GOOD LUCK ON THE REBIULD!!!
Firing Direction
Maybe I read the circuit wrong, I'm a mechanical engineer/metallurgist, not an EE. However, the Buick shop manual says, and I quote; "Because of the direction of current flow in the primary winding and thus in the secondary winding, one plug will fire from the center electrode to the side electrode, whle the otehr fire from side electrode to center electrode." Only one end of the primary goes to ground, so current flows in one direction. Each primary coil has a blue lead, which is "hot", and striped lead, which is ground. Looks to me like current flows from hot, to ground, builds magnetic field, primary circuit opens, field collapses, secondary builds voltage in opposite direction, plug fires. But I can't see how it would fire one direction on one stroke, the other direction on the other stroke. Especially since there is no "TDC on compression" signal. The injectors fire on compression, but the ignition fires the same way on compression and at TDC on exhaust. At least that's what I think.
Maybe I read the circuit wrong, I'm a mechanical engineer/metallurgist, not an EE. However, the Buick shop manual says, and I quote; "Because of the direction of current flow in the primary winding and thus in the secondary winding, one plug will fire from the center electrode to the side electrode, whle the otehr fire from side electrode to center electrode." Only one end of the primary goes to ground, so current flows in one direction. Each primary coil has a blue lead, which is "hot", and striped lead, which is ground. Looks to me like current flows from hot, to ground, builds magnetic field, primary circuit opens, field collapses, secondary builds voltage in opposite direction, plug fires. But I can't see how it would fire one direction on one stroke, the other direction on the other stroke. Especially since there is no "TDC on compression" signal. The injectors fire on compression, but the ignition fires the same way on compression and at TDC on exhaust. At least that's what I think.
Hmmmmm
Now I am curious... Does it really make a difference which way the spark is jumping as long as it is jumping
I would think that as long as there is a .035 gap, the spark should jump it with the same amount of energy whether it is jumping to the ground electrode or to the center electrode.
Damn, now that I think about it, how the hell do you make a spark jump from the ground electrode to the center electrode??? A spark jumps from a point of much energy to a point having a lot less energy and will take the path of least resistance right? How the hell do you get the ground electrode(grounding to the block) to have alot more energy than the center electrode(connected almost directly to the secondary side of coil??)
Now I am curious... Does it really make a difference which way the spark is jumping as long as it is jumping
I would think that as long as there is a .035 gap, the spark should jump it with the same amount of energy whether it is jumping to the ground electrode or to the center electrode.
Damn, now that I think about it, how the hell do you make a spark jump from the ground electrode to the center electrode??? A spark jumps from a point of much energy to a point having a lot less energy and will take the path of least resistance right? How the hell do you get the ground electrode(grounding to the block) to have alot more energy than the center electrode(connected almost directly to the secondary side of coil??)Spark
A spark will easily jump from a "point" but not from a flat surface. When one electrode is "pointier" than the other (the center) the spark will more easily jump from the center to the side than the other way. By the way, the current runs through the plug wire, through one plug to block, through the block to the other plug, then on to the other plug wire of the pair, and back to the coilpack. By the way, you can look at the plugs, and tell by the way they wear which way the current flows. The spark takes away material as it jumps, so the "hot" electrode wears, the other electrode not as much.
A spark will easily jump from a "point" but not from a flat surface. When one electrode is "pointier" than the other (the center) the spark will more easily jump from the center to the side than the other way. By the way, the current runs through the plug wire, through one plug to block, through the block to the other plug, then on to the other plug wire of the pair, and back to the coilpack. By the way, you can look at the plugs, and tell by the way they wear which way the current flows. The spark takes away material as it jumps, so the "hot" electrode wears, the other electrode not as much.
