As promised I would update this post with the resolution to my issue of misfires at high speed or quick acceleration. I came across a thread on this forum in passing that mentioned the seal on the airbox housing may need to be replaced and I could get one from Rob at Needswings (Super great and very helpful). As stated I have performed every test on the engine I could imagine (to my limited ability). Fuel system, ignition system, intake, sensors all new except the air box. I order 2 seals from but only received one. I installed the seal on the 2005 coupe and I noticed the rubber bearings on the valve cover which the airbox brackets clip onto were kinda worn down, so I decided to move them around to get a tighter fit. Well the seal and swapping the rubber bearings made the car feel more responsive and I could tell I was close, but still needed to test to see if I could do above 110mph. I received my seal for the airbox on the roadster and decided to inspect the coupe at the same time I install it. I found the airbox slightly raised on the coupe. I removed the airbox and took a look at the metal brackets that clip the airbox onto the rubber bearings on the valve covers and found the brackets to stretched rather wide. I got my angled pliers and slightly crimpped the metal brackets on the airbox housings. The airbox fit on the engine much tighter. Well this morning I was able to jump onto the highway and really get on it. I got it up to 125mph no misfires. I did accelerate quickly several more times, but not to that speed. I confident that resolved the issue due to the fact before if I WOT it misfire from 15 - 60. That being said if your are experiencing random misfires one more thing to check is the fit of the airbox.