Can i install an external wastegate on the stock turbo? I'm planning on running a test pipe and have heard it can cause boost creep. So would running an external wastegate help control the boost or am i better just keeping it how it is?

 

not true... I've seen a mod'd s4 manifold with a tial wastegate.
Basically, the stock wg was closed, and a short runner was added with a flange for a wastegate.

 

Anyone have more into on this? I was considering closing the wastegate off on my stock turbo and running a much larger external wastegate to hopefully control boost creep completely on a NA turbo. I know i'll need to modify a manifold hopefully this will make the turbo fit better too

 

im running a ew on my stock turbo, well first it was a stock turbo but with the compressor housing change to a to4b, i t work great until i blew my turbo lol, im waiting now for the stock turbo to arrive to mount the ew to it. heres a pic of what im running,(this is not my actual turbo but it's basically something similar) i have my ew on the exhaust housing of the turbo.

 

was that hard to do? i don't see how the wastegate side seals from the turbine outlet. I might put mine on a modified tubular manifold

 

The wastegate is sealed from the turbine discharge from that piece of steel I machined to fit between them.

I used that with the external wastegate because it was already there from when I had the internal wastegate open vented.

The easier way to seal it is to machine the turbine outlet inner diameter larger in a lathe, insert a short section of pipe and machine the whole sealing surface flat again .

 

im running one on my stock hotside.. garrett coldside , unfortunatly the oil seals blew out the other day so i had to pull it and replace it with a hybrid s4/s5 turbo.. its so quiet now and the pictures suck i know..

 

Nice work, but the placement of that wastegate is still goign through the stock holes. That is your restriction right there. If you take out the flapper door, your going to have to seperate the exhaust coming out from the turbine and the wastegate gases

 

well mine works fine so i have no worries...

 

Oops, sorry. I took a 2nd look at it and saw it was seperated. Nice work

It would b nice if it was sealed a little better where the plate bolts to the turbo. So that the boost wont leak as much

How are the pipe threads and fittings with the heat of the turbo?

 

its actually sealed up great! my friend welded the wastegate plate to the turbo because it was leaking like mad before. im getting the turbo rebuilt right now.. should slap it back on the car once its done! i miss that thing already and its only been 2 days since its been off the car.. heres a short vid of the amazing sounds it makes http://youtube.com/watch?v=WIIgSR-hcpA ... and 1 more just for the hell of it http://youtube.com/watch?v=fUprGRtyshY

 

Its actually the sealing between the exhaust gases coming out of the turbine wheel and the gases coming out of the wastegate. If you dont have a way of seperating those or sealing it, your basically loosing boost pressure, kind of like if your wastegate is open a bit all the time. Like on this picture

Im not sure if the pic. The pic on rx7legend's post. its not the biggest problem, the turbo just wont spool up as fast and as powerful.

 

The s5 wastegate is fine, just port it a little. I have a to4 hybrid and its fine on stock wastegate