MSD 44 earth trails down plug sides

Hi Guys,
I have an MSD 44 amp mag with points box in my doorslammer, its a billet BAE, using a six shooter and NGK 6061-10 plugs.
Problem I have is that during a run the plug will stop working and the cylinder goes out, sometimes up to 3 plugs on each run. They are NGK 6061-10 plugs set at .018" gap and we have found some black earth trails down the sides of the porcelain. Spoke to MSD and they sold me some spark retard grease to apply on the plug but it hasn't stopped it.
Any help would be greatly appreciated.
Joe

 

Replace your plug wires they are now junk or at least the boots on the plug end
wash the boots out with brake clean once in a while, oil and dirt makes them track
they now are carbon tracked and more than likely will continue to do this
make sure the plug porcelain is clean when you put them in

 

Ok thanks John

 

A lot of issues are resolved by properly grounding your engine by running several braided ground straps. We grounded the block to the chassis (even though it's bolted in), both of the heads (we did it at one header stud per side), and the ignition ground all tied to the same point which was a stud welded to the chassis near the points box. Some will tell you they've seen witness marks on the tops of the pistons indicating that without proper grounding the spark is firing from the plug to the top of the pistons.

Also, .018 is considered pretty wide although many do it. Try reducing your plug gap to .015.

 

We have both heads and block earthed to the chassis and back to the coil.
I will try .015 gap next time.
thanks

 

Check the depth of the terminal within the boot. The terminals can, over time and for other reasons, work their way closer to the end of the boot. I'm thinking the grease could possibly help enable this. If this happens, the boot will not fully seal (insulate) to the porcelain and the spark will find the path of least resistance and jump to the tube or cylinder head. Hence the trails in the boots/porcelain. There is a step on the inside of the boot that the terminal should typically be even with when properly assembled. Also grounding issues as mentioned above.

 

John Hart is correct, the boots are junk after you get a carbon track down the porcelain.
We had this issue and found that it was caused by oil getting into the relief in the head around the plug not being cleaned up before the valve covers and plugs are installed. The oil gets transferred to the rubber inside the plug wrench and then onto the porcelain of the plug which burns and actually cuts a groove into both the boot and the plug. We solved this by cleaning out those plug wells before installing the covers, wiping the outside of the plug tubes and by spraying inside the wrenches and inside the boots EVERY RUN with electrical contact cleaner. As a side benefit the boots slide on really nicely and then really grip the plug if you try to pull them off a few minutes later. You do need to have decent plug wires but if there is enough energy to arc the 2 inches to the plug's case, that is not your problem; you must replace the boots however. Look inside them and you will see grooves burned top to bottom.
Jeff Johnsen

 

The wire are old and I will change them. We also had an oil leak at the quick release breather tube which did fill the # 3 plug tube with some oil, and that is one of the cylinders effected every time.
I will take all the advise given and replace wires, and clean plug holes and tubes every run.
Thank you to all who responded.
Joe

 

I used to ohm check the wires a LOT, I changed the plug wires every 20 runs whether they needed it or not (or sooner if we had some severe tire shake more than a run or two), and like Frank Manzo, I changed the coil wire every time I took the car to a race.