This turbo actually spools up faster than the old Turbonetics t66 that was on there, I would have lag all the way until 4500 (wtf i know!) and then hit boost. With this turbo it starts whistling at around 3k and Im in boost by 3500. Its a great turbo. The place i bought mine from just dropped the price to 650.........http://miketurboinc.com/products.php?product=S300SX3-%252dS366-

You will also have to buy the flange and the flange adapter, also a oil restricter and the 2 bolts that you put next to the oil inlet, for some reason the turbo didnt come with them, but we had another borg warner around so we pulled it from those.