Internal wastegates and exhaust flow options.

[subsonic]

I was re-reading Maximum Boost by Corkey Bell this morning while sitting in the only room in the house where I can get some piece and quite.

I was looking through the section on wastegates.  While an external is the best setup, the internal is in wide use.  It appeared that the biggest detractor for the internal wastegate was the reintroduction of exhaust gasses back into the flow exiting the turbine, causing turbulance and affecting the speed of the overall gasses going down the DP.  

Can an internal wastegate be modified so that waste exhaust gasses are vented into a seperate exhaust pipe, instead of back into the original stream?

As a additional question, There is a picture in his book of adapters that place the wastegate between the turbo and the manifold.  Could this option be used to allow the use of an external wastegate on a internally wastegated turbo?  The original wastegate would have to be modified so as not to open, but I belive this has been done before.

Thoughts?

[jimfoo]

As a additional question, There is a picture in his book of adapters that palce the wastegate between the turbo and the manifold.  Could this option be used to allow the use of an external wastegate on a internally wastegated turbo?  The original wastegate would have to be modified so as not to open, but I belive this has been done before.

Thoughts?

I don't see why not. I was going to place an external wastegate between my VNT and manifold before I decided that it probably wouldn't be needed. I even bought it and had a plan to put it in my adapter that I made to fit the 3 bolt flange to the 4 bolt manifold.

Can an internal wastegate be modified so that waste exhaust gasses are vented into a seperate exhaust pipe, instead of back into the original stream?

Probably depends on the turbo, but I bet you could make a solid flange with an internal plate to separate the exhaust streams and route them to external pipes. I don't think it would be feasible on my k-14 as the wastegate was inside the housing and shrouded from what I remember.

[subsonic]

Much higher   I think I will be able to go well into the 30s with mine with the porting on the 1.9 head, Giles pump IC and the 3"DP.

I was hoping someone had some info on routing the wastegate stream into a seperate pipe instead of back into the flow.  Some internal wastgated turbo's can do this.  I just did not know if it had been done on a T3 yet.

Manual boost controller will be a must, for sure.

[KTMAuto]

so trying to get more boost out of a t3.  Disconected what i thought was the hose to the wastegate (internal) and the boost didn't change, still 10psi.  Does the waste gate open a set pressure.  My other t3 only goes to 8 psi  Both vehicles have 3 inch down pipe with only 3 inch resinators, air intake is large on both with pod filters.  Need more boost.  Trying to tune to boost.  No wastegate, just turn down the fuel if your scared.  Its how all the oldtimers use to tune tractors for pulls 'round here.  I eventually removed hose, cap both ends, still nothing

[subsonic]

It's a mater of the waste gate AND the fuel.  More boost means more fuel.

[TedV]

l) and the boost didn't change, still 10psi.  Does the waste gate open a set pressure.

there is a pop off valve in the intake to prevent excess boost on stock cars in case waste gate sticks closed.

[KTMAuto]

No blow off on my motors.  It not a lack of fuel.  Have turned up fuel, it is definately the wastegate opening.  The boost climbs fast on both these t3 motors and just stops at set points 8 and 11.  Need to weld this thing up...

[KTMAuto]

So the t3 on the pickup is now running 25 psi.  Hose disconected, and capped.  The the jetta has the same turbo, only makes 8 psi.  What the...?  The waste gate can be frozen, i'd have boost.  Don't understand, if the wastegate doesn't how much boost, how can it open a 8 psi?

[subsonic]

Perhaps it is time for the wastegate to be opened up for inspection.  I have read some of the posts here about frozen or cruddy wastegates.  They looked nasty.  The seat that they seal on also gets way nasty looking.  Andrew has cleaned the seat up before with a lapping compound I think.  I would really like to take my wastegate apart for a inspection and cleaning.  Has anyone removed the actuator and wastegate from a t3 before?  If so I would appreciate some guidence on how to get it apart.

[TedV]

Has anyone removed the actuator and wastegate from a t3 before?  If so I would appreciate some guidence on how to get it apart.

I asked that question here but got no reply.  I'm starting to get a complex asking questions no one has answers to. :?  :lol:

like: what does the return line from the waste gate do that goes to the bottom of the tubo inlet?  keep oil in the intake or since it's in the throat of the inlet, provide vacuum to keep the waste gate closed?

I had my turbo off, soaked, cleaned, etc.  There is a 5mm allen socket (if I remember correctly) on the waste gate valve, used that to rotate valve around, back and forth,  flooded the back side of the valve and no fluid came past.  Used shop air to cycle the waste gate, repeated the leak test, no leaks, called it good enough.

Also check all intake hoses for splits. My TDi split one where you can't see it and had low boost around 10 or 12 psi max until I found it

[flapjack]

heres a good disassembly post for the k24
not exatly what you need but, maybe help a bit?  2nd or 3rd page i think they do the wastegate

http://vwdiesel.net/phpBB/viewtopic.php?t=1841&highlight=k24+assembly

[andy2]

Here's a T3 with a better flow option for the internal wastegate.

 http://vwdiesel.net/phpBB/viewtopic.php?t=3252&highlight=garrett+dissasembly

[subsonic]

Now that is very interesting.  As a bit of humor, I am pretty tired right now, I read all the posts on the link like 5 times and was thinking"What the Hell is Andy2 talking about!  No one is talking about what I am looking for."

Then I see it: :oops:


I have not seen this type of down pipe before.  Has anyone else?  This is exactly what I was looking for.  Proof it could be done.  I dont need to have a converter on my exhaust, so I could just run a second pipe off the turbo, and just have it dump into the atmosphere a few feet away.  Add a 2" pipe for the wastegate, man you would have 5" of exhaust coming off the turbo.  Not much restriction there :lol:
How the hell do you redirect the wastegate flow out to the dump pipe???


Still looking for info on how to pull the actuator and wastegate for clean up, etc..

Thanks for the link flapjack.  I found that one while searching a day or so ago.  Good info to have on hand as I have a spare k24 sitting on the shelf next to the stock T3 and the Merc T3.

[subsonic]

I just checked the DP off my K24 and stock T3.   Nothing looked like the above picture.  

Since Jake is currently off line, does anyone know how his wategate setup worked?

[stewardc]

I agree. I have a T3 on my AAZ and also a K14 and a K24 here and some stock downpipes. I have seen nothing like this "dual" downpipe. What's it off?