carb.?

i have a factory 340 intake witha new eld. carb but i guess ones a spreadbore ones not the barrels on carb bigger than intake won't open so i got the dremil out didn't take much but car would barley run put an 1 inch spacer on runs good now but do u think the spacer hurts power and would a thermaqaud work with no spacer i've never had any luck with holleys even new ones