What part of the dump tube would need to be modified to run an internal wastegate? I thought I'd be able to just section off the dump tube portion of the downpipe and cap off the wastegate hole on the exhaust manifold? FM told me there's more to it than that.

I thought internal wastegates just vented to atmosphere and dump tubes weren't necessary.

 

Basically you'd need to connect the external wastegate pipe portion of the DP to the DP turbo flange right next to the main turbo outlet where you'd typically have the internal wastegate and drill out the flange as well. Internal wastegates dump out into the DP either with a bellmouth DP or separated as you see in your pic. If you just drilled out the turbo flange where the internal wastegate is you'd have exhaust emptying right out into the engine bay.

 

weld the internal wg flapper shut and run the external
that's a DAMN GOOD DEAL for that stuff...

 

Makes me want to buy a 1.6 just to run that. That's awesome.

 

Can you control boost w/ a MBC on an external wastegate? I believe the weakest spring for this Tial is .6 bar (9psi) which is alot higher than I'd like to run.

 

Of course you can, but a MBC won't reduce boost under the WG.

 

no it's not, run it as is.


if you block the external port, you'd still have to modify the DP itself to run an internal.....it's not worth the trouble, I'd run that as is and be very very very happy. 9psi is nothing.

 

I have a 7 psi spring in my tial.

 

You can get springs as low as around 3.5 psi for the Tial WG FWIW.

 

Yeah, pretty sure Y8s is running a 3.5 or close to it.