I really dont think you could do one for less than the 4k. I had a friend who had one done for a porsche 968 and it ran 6k, welding and plumbing, the cost of a turbo, flashing the ecu. Plus, with our v8, you probably want to consider the exhaust pressure if you only use one bank of headers. The sts web site does mention ecu upgrades by unichip, and 190gph fuel pump upgrades if you run 6psi-thats for the tundra. Just about any turbo setup will have lag, and depending on the size of the turbo, will dictate the amount of lag. Smaller turbos spool up quickly, but lack top end power, and large ones are the opposite. I've run turbos since 1987 in various supras and porsches and saabs, in various trims from stock to a racing porsche. I must admit, the sts setup is very different, but an extremely viable, and relatively inexpensive option. The trd supercharger was 4700 before it was taken off the market, and it didn't include injectors or fuel pump upgrades other than the fmu, which on my 2000 supercharged 4runner, didn't do didly. I hope someone comes out with a product for our v8s soon!
My question would be, what would be involved in retro fitting the tundra setup to the 4runner.? Any thoughts?
Thanks