24-09-2014, 05:04 AM
Realistically it'd cost maybe £2000 to go "stage 3", but that's doing it properly with new clutch, new dv6 pressure sensor, reconned r70 pump, reconned larger turbo, reconned injectors with jtd tips, etc. Most of the options centre around the turbo, as everything else is fairly limited in what you can do in the way of upgrades. Even then it's relatively simple, make a choice between vnt and wg controlled then find something that makes the power you want where you want it.
Whether or not it's reliable depends on how you do it, anything can be made reliable. What qualifies as reliable depends on you too, it's to be expected that a motor running over double the power it came out of the factory with will require a bit more love and care to keep it sweet. But, as slam wagon says, above stage 2 there is very little tried and tested, just a few people with different approaches and experiences. Avoid stuff like hard-cut limiters and torque spiking and there's no reason it shouldn't survive just fine. The main restriction people have been coming up against is the exhaust flow, but a larger turbo, exhaust and ported manifold should solve that nicely, you just need to look at builds like tb205s to know it's possible.
Whether or not it's reliable depends on how you do it, anything can be made reliable. What qualifies as reliable depends on you too, it's to be expected that a motor running over double the power it came out of the factory with will require a bit more love and care to keep it sweet. But, as slam wagon says, above stage 2 there is very little tried and tested, just a few people with different approaches and experiences. Avoid stuff like hard-cut limiters and torque spiking and there's no reason it shouldn't survive just fine. The main restriction people have been coming up against is the exhaust flow, but a larger turbo, exhaust and ported manifold should solve that nicely, you just need to look at builds like tb205s to know it's possible.