As far as lump or no lump, well, when you are forcing air/fuel into a cylinder, your cylinder head design is less critical.
Adding lumps will help, so it would be worth doing.
Too bad Tlowe did not compare a non lump head when he turboed the 250 on the dyno.
MBHD
I think that with the results shown to him/us with the lump/no lump combos that were tested it would be safe to say that the same results would be expected to be seen when compared to a turbo engine if you did or didn't use lumps in that type of application.
