i would get a turbo if you have the funds. plus if you wanted to get a vtech head you would have to do other things for that head to run correctly on a ls block..like getting a gsr water pump,oil lines...etc..just some of the things i know you need. and your going to get the best bang for the buck with the turbo kit. and ls motors can handle 7-9 psi on stock internals if tuned correctly. oh and if your car is completly stock then i would suggest starting off with the basics like intake,exhaust,header,hi-flow cat,etc... hope i helped......