I need some puckin' advice

[Paul Clark]

In an attempt to get the boost down where I can have some control over it (24lbs. through the lights with the rod backed down as far as it will go) I took off the turbo and found the following -
The ATR downpipe puck is 1 3/4".
The hole in the turbine housing is 13/16ths.
The carbon pattern is not centered, but the narrowest edge is covered by at least 1/8".
What should I do, and how should I do it?
Thanks
Paul

 

[Quick6'n'-K.C.]

The ATR downpipe puck should be 1.50 inches and since your hole is bored out on the turbo to a larger diameter, it should work fine.
Since it is being covered by 1/8th of a inch, your good to go.

Are you sure that your wastegate arm isnt too short?
Did you make the wastegate yourself, how long is the rod?
How far do you need to pull the arm ilet to get it over the puck arm?
What type of boost controller are you using?

Perhaps the wastegate diaphragm is blown and not pushing the arm out to releive pressure under boost.

Easy way to tell, loop the compressor housing tit to the wastegate, you shuould get about 11-13psi of boost, if its higher, your wastegate rod is too tight or the wastegate is shot.

Have you used a mityvac to check pressure on the wastegate and see if it leaks?

BW

 

[chris2316]

dremel tool , carbide bit and go to town , i have done this on the car before on several cars works like a charm! just make sure you keep within the carbon tracking by at least 1/16

 

[Paul Clark]

So I wind up with an oval shaped hole, correct?
Do I taper it a bit?
I'd like to provide more info, but all I know about the turbo is that it is a hybrid, which is a little bit bigger than a GT3255.
The actuator bracket is attached with only one bolt and a spot/tack weld instead of 2 bolts, so it's kinda hard to go back to the stock unit.
Thanks for the replies.
Paul

 

[chris2316]

try to get it as clean off a circle as possisible , so it doesnt look bugared up!

 

[2QUIK6]

Mine was off center as well so I opened it up with a dremmel and a carbide tip cutter, so now its a little oval shaped, won't hurt a thing..I also smoothed out the inside of the WG hole...you can stick your finger in the hole and feel around and you will feel a sharp edge, even a 90 degree square edge at some points around the hole that you can smooth out for more air flow if you can't open the hole up anymore...but you have to remove the exhaust housing to do this.

 

[UNGN]

Like Rob said, don't go crazy opening the diameter of the hole if the inside of the hole has a sharp edge. Smooth and round all the inside edges, first.

A hole with a rounded edge will flow A LOT more air than one of the same diameter with a sharp edge.

 

[Paul Clark]

Thanks for the replies.
I found an egg-shaped grinding stone that fit on my small air grinder, and it did a great job of rounding off the inside edge.
Didn't enlarge the hole much.
Think I'm good to go? Don't want to take the turbo off again.
Thanks again.
Paul