id go with the 177 as well, i would recommend the 650, ur motors pretty stock and even with 6-8 pds of boost, the motor should be around 400 hp, if u call the techs at summit, hed suggest the same thing, i was actually looking into this before deciding to turbo the car, and my combo was 350 chevy,40 over, flat top pistons with 10. comp, 1.94-1.60 valves on stock ported camaro heads,wiend single plain intake and a 750 carb(go figure,lol), 2200 stall convertor and 3.73 gears on a 10 inch tire. when i told them this combo, he suggested the 650, eventhough i was stepping back in cfms, i was gaining in velocity, and streetability tuning, plus if u want it more fore driving arounjd, u save some on gas....althogh i switched in the end to a turbo combo, this stayed in my mind and so i give u that info, the main thing is to have fun, and not regret what choice u make, this is also why everyone suggest the 177, after a while ur gonna wanna turtn up the wick, and the 142 is not gonna be enough...ever thought of procharging it?u can get one for 2200 in doug herbert and they bring pretty much everything, u dont have to take out ur intake and u can modify ur 650 top be a blow through, plus make more power then a roots type blower....something to look into....