$4000-5000
EIP Tuning is known for its turbo tuning, and starts with its Series B kit for $3500. Since it's not intercooled, boost is set to 6psi, which is good for 245whp at 6400rpm with a 2.5 or 3" exhaust. Full boost happens by 3500rpm, and the 238 lb/ft of peak torque arrives at 4500rpm. The large T4 Turbonetics turbo rests on a stainless steel exhaust manifold with a 2.5" downpipe, and is regulated by a Turbonetics wastegate. Mandrel-bent intake piping, complete mounting hardware and even an integrated engine management system for fuel and ignition are included in the kit. EIP claims it takes 6-9 hours to install, fitting '92-98.5 VR6 Corrado, Golf and Jetta, and even VR6-converted '85-92 Golf and Jetta.
Kinetic Motorsports falls into this category with its stage 2 turbo kit for the '95-99.5 VR6. At $3650, it uses the same turbo as stage 1 but with the addition of a front-mount intercooler, allowing boost at 9-10psi. This is good for around 280whp with a cat-back exhaust. Now that we're getting into Porsche 996 Carrera territory, Kinetic reports an upgraded clutch disc is recommended for use with the stock pressure plate for an extra $225.
VF's stage 2 supercharger for Mk3s and Mk4s is $4000 and $4500, respectively. You get stage 1 plus some Bosch injectors, new software and an 8psi pulley. This should give 250whp at 6400rpm, with a flat torque curve exceeding 200 lb/ft from 4000-6500rpm on the Mk3, and 3200-6500rpm on the Mk4.
$5000-6000
The EIP Tuning stage 1 turbo includes everything in the Series B kit, but adds an intercooler to run 10psi for $4999 plus a cat-back exhaust. The end result is 275whp at 5700rpm. The torquey setup provides 283 lb/ft by 4700rpm.
The VF stage 3 blower for Mk3 and Mk4 is the same as its stage 2 plus a side-mount intercooler (cutting the front bumper is not necessary), new software and more boost from a smaller pulley. The price for stage 3 is $5500 for early cars, $5900 for the Mk4, and will net you around 270whp at 6400rpm on 91 octane.
Upgrading from Kinetic's stage 2 turbo to stage 3 adds 42 lb/hr injectors, with C2 Motorsports software and a head gasket spacer lowering compression to 9:1. Since the kit retails for $3950 it represents serious horsepower for your dollar when it pushes a whopping 350whp on pump gas. But the kit falls into this price bracket because Kinetic claims you'll need its $575 clutch to make use of the torque, bringing the total to $4525 plus a cat-back exhaust. Additionally, as with any kit using a head spacer to lower compression, don't forget extra hours of labor for the head removal.
$6000-7000
Boost Engineering sells a kit that uses a Garrett GT35 turbocharger. There's also a cast iron manifold, front-mount intercooler, 42 lb/hr injectors, Bosch plugs, BOV, 2.5" charge piping, oil pan with adapter, tranny stiffener, K&N filter, heatshield, 3" downpipe and 8.97:1 head gasket. The kit alone is $5280 for Mk2 and Mk3 cars, $5445 for '92-95 Corrados or $5580 for Mk4s because of the necessary catalytic converter. The internally-wasted boost is set to about 14psi. Boost Engineering offers a ceramic clutch for an additional $175, but claims the stock clutch will work on the street. To accompany the 3" downpipe, Boost Engineering has a 3" exhaust, allowing the kit to make 308whp at 6400rpm and 308 lb/ft at 4200rpm.
Take EIP's Series B turbo kit and add the stage 1 intercooler before stage 2 lowers the compression with a head spacer so 15psi is safe on pump gas. When you throw in the clutch upgrade from EIP the total comes to $5880 plus the price of a cat-back exhaust system, but now we're talking 364whp at 6000rpm with 377 lb/ft of torque at 4650rpm on pump fuel - or enough power to keep up with your average Porsche 993 or 996 twin-turbo!