Stock Garrett exhaust housing WG hole size

[dsa87gn]

What size is the diameter of the wastegate hole on the stock garrett exhaust housing ?

I just picked up a TA49 with the garrett exhaust housing and brought it to work today to open the wg hole up a bit so I dont have boost control issues.

 

[turbojd]

I believe the stock wastegate hole size on the Garrett housing is 0.830" and the stock puck size is around 1.12".

 

[dsa87gn]

Maybe Im all set...
The hole measured 1" already...I have a THDP so maybe I can just leave it as it is.

any other opinions ?

 

[RUQWKNF]

I would just make sure to put marking compound on the downpipe puck and check where it falls on your turbine housing.
This is crucial for accurate boost control as not all downpipes are created equally. Meaning, one company might put their puck in a slightly different spot than the other company. But other than that, you should be fine if the puck completely covers the hole.
Just my O2's worth.

Patrick

 

[bison]

Maybe Im all set...
The hole measured 1" already...I have a THDP so maybe I can just leave it as it is.

any other opinions ?

You should have no problems unless you are going to open the exhaust. If so id go to .110 and do a nice blend inside the wg hole

 

[dsa87gn]

You should have no problems unless you are going to open the exhaust. If so id go to .110 and do a nice blend inside the wg hole

by "open the exhaust" you mean open dump ? I have a free flowing exhaust
from turbo. 3" downpipe with dump into hooker exhaust.

I originally posted this question because when I added the THDP, Hooker Exhaust and Big Mouth Air, with my stock turbo I couldnt control boost for $HAT. Even tuner style setup, my boost would go way past 15#. Couldnt run pump gas without knock. I added alky and a manual boost control and run it at 23# and it seems pretty solid.

I think i will definately blend the inside of the hole

 

[bison]

by "open the exhaust" you mean open dump ? I have a free flowing exhaust
from turbo. 3" downpipe with dump into hooker exhaust.

I originally posted this question because when I added the THDP, Hooker Exhaust and Big Mouth Air, with my stock turbo I couldnt control boost for $HAT. Even tuner style setup, my boost would go way past 15#. Couldnt run pump gas without knock. I added alky and a manual boost control and run it at 23# and it seems pretty solid.

I think i will definately blend the inside of the hole

I have the same. I lose about 4psi when closing it at 800hp and it spools noticeably slower. Its not as free flowing as open and it will have an effect on the wastegates ability to control boost when opening it even at 400-500hp. You dont want to have your foot in it and see 28 psi and 20 degrees KR because of an oversight.