From Loba:
The GT3071 build is a big thing to do. I do not exactly know what costs one's looking at if turbo, exhaust manifold and other parts ought to be replaced. Anyhow, I think that the LO380 and GT3071 are quite different characters.
The GT is one big turbo and that surely makes power.
Here's why we do not use an aftermarket exhaust manifold with a Garrett turbo:
Modern TFSI engines run pretty high combustion temps in favor of higher hp output, efficiency and emissions. Now aftermarket headers are made of D5 or D5S steels, as well as Garrett's turbos. D5 is prone to cracking when exposed to constant temps greater than 900°C. The OEM material used is 1.4848 - withstanding constant temps of up to 1100°C.
If you're not stressing your Garrett turbo too extensively for a longer time there should not be any
problem. But since we've been developing our products for the German market where people really drive at WOT for quite a while due to no speed limits selling a product that could fail because of aforementioned
problem would be pretty much adverse.
We have made quite a few experiences in terms of longevity and therefore chose to go that way.
We are developing two new stages of our turbo both of which will be made bolt-on fitment in accord with OEM quality standards. We are aiming at 450 respectively 500 hp.