Hey Guys. Newbie here. I am a 1972 Buick GS455 owner (we are all A-body cousins anyway right!!). I am helping out a buddy with a newly purchased 71 GTO 400. What are some common upgrades/products/part #`s to get a "smogger 400" up in the h.p #`s. Nothing crazy here, maybe 350-360 street horsies on pump gas (91-94 octane). A little bowl work/porting on the heads?..Scrap the heads?.. Cam?.. Intake?.. Headers? Not sure what works best on these Poncho motors. It appears to me that the 69-71 400`s use the same engine hardware except heads and intake..?? This is a TH400/3.23 car so I think a 2500 stall converter should work with this driveline. Any input is great!! Thanks!! Later,Tony.