Mach 1 engine hesitation/ cracking noise from rearend HELP!?!!!

[Cobraman1024]

There is a guy selling a complete COP conversion harness for 96-98 COBRA's. I think it was on SVTPerformance.
Basically you buy his harness and a set of coils.

............Which is exactly why my engine in the Mystic looks like this:





I bought one of his packages sometime earlier this year for about $200. I then went a junkyard and picked up the timing cover ($25) and cam covers ($10 each I think) from a 1999 Lincoln Mark VIII, had them powdercoated the chrome/silver color and that's pretty much it. This picture is from right before the timing cover installation. The studs that the coil pack brackets were bolted to are now shaved to flat-faced bolts. You can see one stud on either side of the glossy black coolant crossover tube (which was also powdercoated).

[bullitt5177]

Not sure if this has been resolved by now, but if not, it sounds likely to be one of the coils. Ford coils are known to get weak under stress. The best way to determine the weak coil (if it is one), is to hook up a spark tester to each coil and look for a weak spark (it will still spark, just not as strongly) under idle. The only other way would be to perform a coil stress test which requires the use of a Ford scan tool. Although, if the car is an automatic, you can have someone load it with their foot on the brake in drive and watch to see if the spark cuts out. The cracking noise is likely popping from fuel being burned in the cat.