Do you think the 600's might have been a bit much for the 289?
I've got 500 AFB's for my setup which is only a touch smaller than the 427 you mentioned. I am running a pretty aggresive solid cam. I was thinking of maybe using Holley 600 vac secondary carbs, but I have the Carters right now.
I have an oil pressure problem to address first, otherwise I'ld have hucked that puppy on there and been giving first hand reports right now.