BAD Arch Good Ground?? Spit and Sputter?
 

I have a big arch coming from the trailing coil and i can figure out why.
The engine is grounded good with a after market big guage cable and from there to the frame rail.
Also the car sputters when its around 4500 to 6500 RPM's.
I think it may be a beacuse of the coil problem.

Any Idea's???

where on the coil is the arch coming from? the terminals or the tower? bad coil wire would be my guess

The arch is comeing from the terminals and going to the tower.

I know it makes no sence but the coil wires are brand new NGK Wires. With no cracks i checked that also

Mine does that too. Right where the leading coil sends its power into the Coil wire to dizzy, it sparks and makes my tach go weird. I have the same symptoms as you, so I covered the coil plug boot with electrical tape and covered up the positive and negative side of the coils. Not the prettiest thing, but it helped somewhat until I go get new plug wires.

see i have new plug wires but it still does it i would like to fix it insted of hide it.
I know the battery cables always go bad but i have good welding machine guage cable on the ground now and still it does it.

Mine did this once and it was because the plug wire was not all the way seated in the coil. I also changed the cap and rotor and it helped but didnt solve the problem entirely.

What fixed it Ian?
By the way how have you been???? Havent talked to you in a while.

Basically what fixed it other than the replacement of cap and rotor was I unplugged the coil to dizzy wire and spread open the part of the plug wire that attaches to the coil. Then I jammed it in there like the bitch it was lol. May also help to possibly take the connectors off the coil and clean them up. Could be a corrosion problem.

I've been pretty good. been hangin out keepin it real. You know how I roll lol. Actually, I start auto body classes on monday. Pretty excited/nervous. The first time I went to college (dropped out) I wasnt near as nervous. I am probably going to be the oldest guy in the class though (27). I do know however that it means a hell of a lot more to me now than it did before.

Coil may have a crack in the top of it, causing a spark leak.

See heres the funny thing i drove it today and had no problems at all.
And no there are no cracks, i replaced it with another good coil just to make sure and it did the same thing last night but today it did not arch at all.

I know you said you ran a good ground to the body, but what if the grounding from the body to the battery negative is lacking? Might be worth a shot...