My 750 Holley (vacuum secondaries) works great on my 383. I ditched the choke, and C&J Engineering massaged it a little...
They did a 800 conversion, drilled the plates, installed a cross tube (instead of the "j" tubes) installed different secondary spring (purple .063), re-jetted (75/86), new nozzle (.033), and power valve (6.5).
No off-idle stumble like my old 750DP.
http://www.planetsmilies.com/smilies/happy/happy25.gif
PS- Travis- 380HP? No worries...