Engine '88 GT Has No Power Above 3000 RPM After Trick Flow 11r Heads Install

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Those compression test numbers look good. Could indicate a higher than stock compression ratio. Higher cylinder pressures won’t like ignition timing that’s too far advanced. The advice to cut the initial timing back to 10 is good.
 
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Those compression test numbers look good. Could indicate a higher than stock compression ratio. Higher cylinder pressures won’t like ignition timing that’s too far advanced. The advice to cut the initial timing back to 10 is good.
I just tried calculating the compression ratio which came out to be 9.7:1, but I can’t tell you how accurate that is given the limited information to calculate it.
 
Unfortunately, we welded a socket on our stock distributor so we could prime the rockers with oil. Just because the fuel pressure is good, could I still be getting insufficient fuel volume? We pulled all the spark plugs Friday and probably 6/8 had white tips which was, I'm assuming, caused by a lean condition.
So you don’t have a way to confirm fuel at wot? I’d recommend getting your wideband figured out. At least you can remove the notion it may be fueling

I’ve encountered breakup at higher rpm before due to a faulty PIP inside the distributor. A crappy signal could propagate and get worse as rpm increases, which could cause breakup or even what sounds like That lean backfire in the video.
 
If you don't get improvement with the new pump and timing setting, there is another trick you can try. Unplug the o2 sensors. When you do this the ECU would revert to a 12:1 steady ratio. It may be rich at idle and cruise but that ratio should support the top end rpm range in your NA setup. I make this suggestion as a test to bypass any issues with sensors and wiring that would normally send signals to the ECU for fuel management. Unplugging o2's would bypass that process and the ECU would pulse for a consistent 12:1. It does not provide a fix for you issue but if there is an improvement with o2's unplugged, it leads you in the direction of the problem.
 
Little update for everyone. Installed the 190 fuel pump and of course had the same issues (even though the fuel pump was a needed upgrade). Did some more research and decided to try and replace the distributor after we checked and then double checked the timing was set to 10* with no change. Well, the auto parts store distributor got stuck inside the housing, which fortunately didn't do any damage to the cam gear. As an absolute last resort, we said what the hell, and swapped the TFI module from the auto parts store one with the msd one. Lo and behold, that was the ticket. Car runs absolutely amazing now, we just have to get it back to the dyno. It's very frustrating having out of the box parts be bad, especially with a brand like msd, because we were just chasing our tail. I will never buy an msd product again.

Thanks for everyone who responded!
 
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