open-vented wastegate on stock turbo
 

Has anyone ever done this? do you think it would help the wastegate flow more efficiently? it looks like it would be a pretty damn easy mod, just weld onto the stock iron thing on the turbo where the DP bolts up and cut a hole in it, and weld a pipe to it.

It's not quite that easy actually. If you want to leave the wastegate outlet open, you have to make an air-tight seal between the turbine outlet and the wategate outlet, or you'll have a massive exhaust leak and a very loud engine. It's do-able (and has been discussed here several times before), but not the way you've described.

The exhaust flow is already free because of your 3" downpipe.
The waste gate port is the main restriction.

Maybe just enlarging the flapper door, wg port, and possibly even modding that plate between the dp and the turbo so that the wg flapper can open farther would be easier and more effective than trying to open vent the wg.

There is a friend of mine Kraig, he is a Modd on nopistons and he JUST got finished putting a Tial 38mm external wastegate on a stock turbo. I might be able to find or get some pictures but he said it was a bitch, oh he also works at a machine shop lol I believe his screen name on here and nopistons is ILUVMY88CABRIO

That turbo backing plate is a special high nickel content metal.
Isn't a royal pain in the ass to weld to.
Good luck.


-Ted

Here is a link to some of the progress pictures, the show the sleve he had to make and a few other things.

http://www.nopistons.com/forums/inde...pic=35626&st=0

I open vented the stock WGs on my S5 and now it has an external 60mm WG (about as big as the turbo itself).

Like Ted said, welding that cast iron is no fun and likely to cause cracks- I made everything bolt together instead of welding.

http://www.teamfc3s.org/forum/attach...&postid=255420

It is divided inside the WG extension so the turbo is still fully divided.

hmm.

okay, thanks!

BLUE TII,
Any more pics of it, especially inside?
My wastegate actuator is shot and I am thinking of putting a Tial 38mm on a new backplate with a pipe going into the int wg hole.

These pics are frpm when it was smaller "O" trim exhaust wheel and before the wastegate extension was divided. I will get some updated pics soon.

http://www.teamfc3s.org/forum/attach...&postid=255416


http://www.teamfc3s.org/forum/attach...&postid=255417


http://www.teamfc3s.org/forum/attach...&postid=255418

damn that's pretty sweet.

I guess it's big enough!!

No it wasn't big enough!

Here are some more pics of it in its current spec

The divider in the wastegate extension is welded on the turbo side and then welded to a floating ring on the wastegate side. I had to do this to allow it to expand along its length.

The 1st one was welded at all 4 corners and broke the welds at the WG end and then vibrated untill it broke the divider right where it goes into the WB extension.

The turbo housing srolls apertures where the exhaust gasses are introduced to the turbine are cut to double stock width and the center ridge is cut back to make the rear aperture angle less forward than stock.

Here is a comparison of the "P" trim exhaust wheel and a stock one.

Also shown is some of the finish work- though it is hard to see in the pics. The compressor outlet is smoothed and the outer edge knife edged to meet the sil. coupling smoothly. I did this to all of the intake. The turbo manifold and housing runners are polished- obviously, not shiny after running, but only a smooth dusting of carbon sticks to them.

That is amazing work! How much did all of this cost you?

? cost of hybrid turbo and wastegate and a little for the welding.

In terms of time...lets just say hours and hours of free entertainment!