Every GA GT(v6) is 175HP stock (RAM Air, different transmission ratios for shifting 'same stock shift points I think' and better handling) You have the GT and the GT1 trim options
The GA SE(v6) is 170 Stock (not to big of a difference, different ratios as from the GT 'GT being better', handling is good but dunno if its up to GT standard but like most cars can be fitted with struts, strut bars, lowering springs... theres only really trim level difference ... the SE and the SE2.. Same stock 170HP)
Most aftermarket parts for any grand am will fit either a GT or SE so its really not to much of a difference except for the transmission ratios being slightly different.
So if you can pick up a GT, but likewise an SE is just as great just not as good around cornors I would think ... well mine isnt =) More of a straight forward car. (drag-n-such, or 40,50,60 rolls)
Going from a stop in a stock Grand AM isnt exactly all too good for the auto trans
Auto Consumer Guide - 1999-2005 Grand AM SE/GT Info/Specs
Check it out