Help..Driving to work and...

[speedytang]

I was slowly accelerating and when I hit around 4500 rpm it was like hitting a rev limiter which is usually means your blowing out spark. My problem with that is my plugs are gapped .035 and I didn't look when it happen to see if the fuel pressure was holding or not. I have a HO255LPH pump in tank but have not installed the REX pump yet. I was only at 5 psi of boost and part throttle when this happen. I have a MSD Digital 6 and I guess what really bothers me is my Dad has a 90 Conv LX and with his Vortec A-Trim putting out 5 psi full throttle and his plugs gapped at stock .054 with no ignition box he has no problem with this that is why I always wonder when people talk about spark blowing out if we need to be doing something else other than closing the gap on the plugs because then I bet my power down low will suffer and my fuel mileage will drop. The factory went to hot ignition so you can open the plugs and get that nice fuel mileage rating.