Difference between NA cylinder head and the Turbo head

[mysticj]

evo 1-3 and gvr4 cams are 252 duration on intake and exhaust with 9.5mm lift on both cams.
us 4g63 for turbo and na are supposely 256
unsure about lift

[silver_beast98]

thanks. i was wondering what the difference was because i have a 1g head and both sets of cams. im building a motor over the summer and its going to be NA, at least for a while. i'd like to put some aftermarket cams in it but i was wondering if either set really had any benifits over the other if not.