misfire and hesitation

I have a 95 cobra with a 302. There is an e cam in, trickflow intake, 75mm throttle body, 80mm MAF, stock 24lb injectors, and msd 6al box with blaster coil. ok now the problem is that especially when cold there is a misfire and hesitation present especially at 3k-4k RPM. when at operating temp the issue is not as prevalent but still noticeable. I disconnected the msd but still have the problem. I checked all basics vacuum lines intake leaks, timing, plugs and wires, cap rotor, cleaned MAF, injector cleaner, compression test and leak down etc. I have no faults stored and my sensors are reading correctly. Also note that the car was tuned with all mentioned parts above at a very reputable shop and has driven excellent for a year. Has anyone heard of something that just might cause this or expierenced it and remember what the fix was or have any more suggestions?