any real advantage to getting it in stainless steel? i plan on getting the downpipe temp coated...so would it really even matter if i get stainless or not? and I have been looking back and forth and not really sure if i wanna go external or internal wastegate...if im not going huge turbo yet its not really necessary to get an external gate?
Stainless is desirable because of it's resistance to corrosion and because of the temperatures and pressure that exhaust gasses produce. It's more important upstream of the turbo. The biggest thing that the downpipe does is dump the exhaust as quick as possible so you don't have backpressure preventing the turbo from spinning freely. However, as I learned, if on an internal gated system you don't have your flange made from stainless it's susceptible to a sticking puck and you'll overboost.
As far as internal and external, the choice is yours. Most turbos will work just fine with internal. External can cause problems if you have a visual smog inspection. External also run with a manual boost controller, internal can be used either with a manual or stock computer/wastegate solenoid setup.
Yea, the car doesnt have to go in for emissions anymore..
Im just looking at options...its making more sense to just go stainless...but now the choice is external or internal..and thats where i get confused haha
You may struggle with boost control with internal, but people have made it work with wastegate hole porting to match puck size. You can control boost pretty well with internal. External gets rid of the puck, it's just a different method for controlling boost.
Put it this way for you, I have a pretty new BMW 335 and they still use an internal gate system. They have pretty good performance engineers. It still works just fine.