[iaknown]

Originally Posted by glitdi

iaknown..
Did you pull the turbo to hog out the wastegate hole? or did you do it on the car? Rag to keep the metal out?
I don't remember seeing a procedure mentioned any where?

Did the mod with the turbo still on the car. Just needed to pull the engine mount for proper access. No rag although not a bad idea. You are working beside the turbine wheel so very little is going to go near it, the only thing I was concerned about was when breaking through on the other end of the hole, which is in front of the turbine wheel. But when I was done I used a shop vac to clean the mess out of everything, especially the wheel area just in case.

[TDIwyse]

Originally Posted by TDIwyse

...Won't get to that until next week due to other responsibilities and time commitments. Will report back on findings.

Was able to sneak some testing in last night as the pavement dried out enough in some patches to be able to do 4th gear pulls. But Old Man Winter is making testing difficult. High today is -8F ...

So I have a configuration now that seems to be very promising. The analog gauge shows (sorry, no video's yet) boost staying below 30 psi everywhere, and the ~2800rpm spike is completely gone. And I kinda like the sound when the wastegate dumps to atmosphere ... Yes, I'm a bit Redneck.

Boost log comparison of 4th gear pulls with and without the external wastegate. Data from before the external wastegate is from this thread: http://www.e90post.com/forums/showpo...5&postcount=75

Note: The Android Torque app reads ~ 4 psi lower than the analog gauge at peak boost levels.

[Puerto Rican 335d]

Tdi thanks for your response, this thing seems VERY promising!!!

[joe_planet]

TDI, I'm trying to read the second graph, but both blue and red lines are the same in the legend, what should they be?

[TDIwyse]

Originally Posted by joe_planet

TDI, I'm trying to read the second graph, but both blue and red lines are the same in the legend, what should they be?

Ah, I should've mentioned that those were two separate pulls on the same test drive.

[2deerwhistlers]

Originally Posted by TDIwyse

Ah, I should've mentioned that those were two separate pulls on the same test drive.

High tech redneck..

[polo 335]

Originally Posted by iaknown

So as some of you know I have been pulling every last hair out trying to solve my overboost issue. I think I finally have a solution.....

So to get everyone up to speed, I am running open exhaust. I thought this was the cause of my overboost but it turns out it wasn't (though it definitely makes it worse). I got a hold of the stock/SCR midpipe for the car and put it on and I was still overboosting. Probably just a psi or 2 but enough to set the "Boost Sensor Range" code while running Jarek's stage 2 tune. Running the stock midpipe just like most of you are told me something else was wrong on the car. With Jarek's help as well as the help of a few of the members on the forum I ruled everything out. Even replaced my boost sensor and wastegate solenoid (pressure converter), still no dice.

So I finally ended up opening up (porting) my wastegate in the car. See before and after below. Had to remove the downpipe and engine mount again to do so but it appears to have come out ok (no holes ). After logging boost with no exhaust (downpipe only) I am right where I should be, so it made the difference I needed.

If you plan to run open exhaust you will probably need to do this to stay in the safe zone. Also, if you are running another tuner besides JR Auto's and you don't get codes with straight exhaust, your warning codes have probably been tuned out, you are still most likely overboosting, and probably slowly hurting your turbos.

It also sounds like another member will be presenting another solution (though a bit more involved) shortly .

Very clever mod Iaknown. I encounter the same overboost issue with my 2007 european car and I will certainly do the same mod. Thanks What diameter is the new wastegate? Is it possible to create an underboost issue if the hole is too large when the wastegate is opening?

[TDIwyse]

Originally Posted by 2deerwhistlers

High tech redneck..

Absolutely.

What I really thought would be Redneck would be flipping the wastegate orientation 180, modifying the BMW emblem on the hood to be a flapper cover, and then dumping the EWG out that. :-)

[2deerwhistlers]

Originally Posted by TDIwyse

Absolutely.

What I really thought would be Redneck would be flipping the wastegate orientation 180, modifying the BMW emblem on the hood to be a flapper cover, and then dumping the EWG out that. :-)

Yeah.. Forget the downpipe.. I'm gonna build a hood stack.. With little wastegate stack next to it..

[TDIwyse]

Originally Posted by 2deerwhistlers

Yeah.. Forget the downpipe.. I'm gonna build a hood stack.. With little wastegate stack next to it..

Ha! Please post a pic. There's lots of diesel pickups around here with stacks. Would be fun to roll up next to one of them with a little baby bmw diesel with stacks.

[gtp900]

Originally Posted by 2deerwhistlers

High tech redneck..

Could you post a sound clip? I also like this sound, I used to have a stage 3 Audi with a loud bov, it had straight 3" exhaust as well, not too loud, but you sure could hear the turbo whistle

[TDIwyse]

Originally Posted by gtp900

Could you post a sound clip? I also like this sound, I used to have a stage 3 Audi with a loud bov, it had straight 3" exhaust as well, not too loud, but you sure could hear the turbo whistle

I'm hoping to do another video/sound clip. But the weather is just horrible now. -10F and falling to -20F tonight. That's air temp, not wind chill... Which was -40F today.

Weather doesn't look good for the next couple days. This weekend might be OK if it doesn't snow...

[gtp900]

Originally Posted by TDIwyse

I'm hoping to do another video/sound clip. But the weather is just horrible now. -10F and falling to -20F tonight. That's air temp, not wind chill... Which was -40F today.

Weather doesn't look good for the next couple days. This weekend might be OK if it doesn't snow...

I hear ya, schools were closed here today, we had -36F windchill last night/today, cold sucks!

[2deerwhistlers]

Tdi I'm just joking about the hoodstack on the BMW.. In the process of playing with a dodge which will receive a hoodstack and my p-pump 24v is getting a fresh rebuild and forged pistons after 8 years of 800+ hp

[TDIwyse]

Originally Posted by 2deerwhistlers

Tdi I'm just joking about the hoodstack on the BMW.. In the process of playing with a dodge which will receive a hoodstack and my p-pump 24v is getting a fresh rebuild and forged pistons after 8 years of 800+ hp

Love it. I've got a Cummins/Dodge as well. Common Rail though...

[2deerwhistlers]

This video shows a hoodstack with a small wastegate hoodstack, and then a turbo explosion.. Ryan bean of beans diesel.. Super nice guy

[iaknown]

Whoa! I leave this thread for a few hours and you guys are ready to slap a confederate flag on it with some train horns!!

Man that truck leaves hard!!

[CO335D]

Originally Posted by 2deerwhistlers

This video shows a hoodstack with a small wastegate hoodstack, and then a turbo explosion.. Ryan bean of beans diesel.. Super nice guy

Haha, that's awesome you posted this 2deer. That's my buddy Ryan Bean's C10 with a CR 6.7L in it. Same guy that built the motor in my truck that I posted in my first thread. That truck is crazy going down the track!

[gr8whte]

Originally Posted by 2deerwhistlers

This video shows a hoodstack with a small wastegate hoodstack, and then a turbo explosion.. Ryan bean of beans diesel.. Super nice guy

Ctrl+Z
Ctrl+Z

Sorry couldn't help it...

[iaknown]

Originally Posted by polo 335

Very clever mod Iaknown. I encounter the same overboost issue with my 2007 european car and I will certainly do the same mod. Thanks What diameter is the new wastegate? Is it possible to create an underboost issue if the hole is too large when the wastegate is opening?

New diameter is 9/16" (14.27mm). If you were to go too big, or if it makes more of a change on your car, there are some options....one of which is putting more preload on the wastegate actuator.

[TDIwyse]

Roads were dry enough to do some further testing and get a video. This is a 4th gear pull with full fuel (plus a lot of water/methanol) going up hill (to help load the turbo). Also attaching the android Torque log info (it's pretty consistent at measuring ~5psi lower than the analog gauge).

This data is looking a lot better than the overboost situation from post #3 in this thread (boost peaking at ~37-38 there).

The rpm's where the little turbo is involved is at lower peak boost #'s now, likely because the back pressure is higher there until the Big Turbo path is opened, so it's helping open the EWG at lower manifold boost. I could probably do some more tuning with a boost controller (don't have any in play yet), but I kind of like the impact this has on the low rpm peak wheel torque, as it's lowering those numbers, and full torque doesn't come online now until ~2900 rpm when the big turbo takes over. I like this as it'll have less stress on the transmission/drive train. Plus I was having significant traction issues at those lower rpm's, even with extreme summer tires and the Quaife LSD.

So far I'm liking this.

[gtp900]

TDI, is the clicking sound the wastegate?
I didn't here any "whoosh" sound? Maby mic didn't pick it up?
I would think, (at the track) this new set up would be slower.
Just a question, has anyone considered "building" the tranny? Has anyone ever "broke" their transmission yet from excessive power?