TE 60 Boost Creeping

[joed]

I’m running a Craig TE-60 with Garrett housing, 1” exhaust port, THDP, HD actuator, RJC boost control (for better spool, no “Y” or solenoid used in control line) The boost, read from 3 Bar MAP on Turbo Link goes up to (for example) 22.0 then down to ~21.3 (during 35-70 mph) and creeps up to 22.8 by the end of the ¼. I searched the site and can’t seem to find any answers. I know I’ve seen it addressed over the years…Any ideas where to start looking for how to solve this issue? I’d like it to stay at 22.8 (or wherever I set it) the entire run or a tad higher in 1-2 and drop a notch near top of the quarter. While my MPH is good for where I am right now (110-112), my ET’s are not (12.6 to 12.8 range), especially in the 1/8th (8.3’s).
Thanks, Joe

 

[2QUIK6]

You can try putting a radius curve in the exhaust housing around the WG hole to help flow more air out of the 1" WG hole you have.
Place you fingure inside the WG hole and you can feel a sharp edge around most of the hole, about 75% of it...take the exhaust housing off and use a dremmel to smooth out that sharp edge, this will allow for more exhaust to escape thru the WG hole to control boost.
If that does not work, and you are happy with the current spoolup, you can try opening the WG hole slightly more. With my GT61 I have mine opened up to 1 1/8" and smoothed out inside before my boost was constant...but I have a smaller 31E exhaust wheel which is equivalent to a TE44 setups exhaust wheel.

 

[joed]

try putting a radius curve in the exhaust housing around the WG hole

That's a good thought, 2QUIK6. I thought John took care of that when I got it from him, it seemed pretty smoothed out, but that was a coupla years ago, I can't remember what I had for breakfast I'll pull the DP off and take a look. Any other suggestions? Any similar issues seen with RJC boost controller or plumbing the way I described? Anyone?
Could opening the dump help? Could this be a backpressure issue? or backpressure a contributor? I'm using an old (circa '88) 2.5" cat back flowmaster (I think).
Thanks, Joe

 

[joed]

will I need to remove and dissassemble my turbo for this? With no other responses it seems this must be the most likely cause?

Thanks, Joe

 

[Joe Lubrant]

will I need to remove and dissassemble my turbo for this? With no other responses it seems this must be the most likely cause?

Thanks, Joe

The suggestion to open the w.g. hole close to 1 1/8" is prefered.
Upon removal of DP you should be able to see carbon tracking around puck area. This should be your guide, and you can see how much more you can open the hole, without causing leakage.

In some cases puck covering the hole alignment, is not centered, so care must be taken when enlarging. Make sure you leave a safe amount so the puck still covers the entire hole.

P.S. A slight change in boost is somewhat normal as engine loads change on shifts etc. Most all spike in 1st, and settle in 2nd, in 3rd engine is under max. load and if boost creeps upward its usually insuffiecent bypass capability of the wastegate (size) for external gates, or in your case Hole size.

Remove turbo, and just remove turbine housing bolts (use some type of thread loosening stuff WD etc.) Once you have the turbine housing off it will make your grinding work alot easier doing it on the bench etc.
Joe