Rundown

96 L31 block New 383 eagle rotating assembly internal balance, ATI Harmonic internal/neutral balance, Stock Flexplate

Transmission was bought on the boards here, Built 700r4
Custom shift kit, Fairbanks "Billet" 2 nd servo, Sonnax "Super Hold" 4th servo, .490" Sonnax pressure regulator boost valve, Alto "Wide" Red Lined 2-4 band, 7 Raybestos "Blue" 3-4 frictions, "Kolene" friction coated 3-4 steels OR Raybestos "Z-Pack", Sonnax "High RPM" pump slide spring, "The Beast" H/D sun shell, New Borg-Warner 29 element input sprag, Sonnax "full throttle upshift sleeve"

Problems:
From day one ive had a vibration at 1900-2100 rpm, Neutral, or driving. I ended up recently unbolting the torque converter, zip tieing it back away from the flexplate and firing her up. She was as smooth as could be in any rpm range. So i initially thought it was the converter, and the people i talked to said it could possibly be the converter. I ordered a new one, same stall speed ( 3200 ) bolted everything up, took her for a drive today and vibration is still there.

Is there anything inside the trans that will make it vibrate at those rpms? Any other RPM and she's good. The input shaft is solid as i checked all that before the converter went in.