88 2.9 No power

[JMilton]

My 88 2.9 has no power when you put it in gear. It's timed properly, has proper fuel pressure and volume, has a new fuel pump, coil, distributor, full tune up, filters, and most sensor have been replaced. Idles fine, and you can throttle it up in neutral without any issues. If you put it in drive and floor it, it will stay running and you can drive it, but it doesn't have any power. I'm pretty confident its not the torque converter or the transmission. No codes in the computer. KOEO KOER tests also reveal no codes.
Any ideas?