With that many miles I would look at getting a 99 or newer low mileage engine to swap out , that way you have a fresher bottom end , you will gain a lot from that alone , then do the supercharger (vortech) because boost puts a bigger strain as does any power adder to the bottom end .
My car had 105000 on it when I put the supercharger on it and it has 109000 on it now . With all those miles on it I was able to put the the screws to a ls1 last night . I paid 3299.00 for the complete kit. Which included 42lb injectors steeda powerpipe 255lph walbro fuel pump and a custom tuned superchip also I installed it myself which saved more money.
I suggested he get a newer PI engine so he can put up some big numbers , I have seen 40K mile engines go for 900 bucks , then bolt a blower on that and he would see some BIG numbers and have less miles on his engine
i don't think that transmission is gonna hold up too well. my friend has a 01 GT and when he added a 100 shot of nitrous within a couple runs at the track his tranny totally ****ed up pretty bad. he is also an auto but he has 4:10's. i don't know maybe yours will hold up.
i say get the Procharger D1 that was what i was going to go with but i put some money on a PP and cams they will go in sometime next month and i want to get a new lowerend with forged internals bored and stroked and then i will set some money on a turbo kit.. i want alot of hp so that is the direction i am heading
Read the article in MM&FF about the kenne-bell superchargers, u could bolt on an extra 162hp to the WHEELS!!! I was going to buy the 9psi kit but they cost to much (almost 5 grand). If you got the money go big, I personally like the roots type superchargers better they make more torque.
screw roots get the non-intercooled Kenne Bell kit and a 99+ GT motor and drop them in. The kenne bell non-intercooled runs $3799 not anymore than most kits really.