Is the 1.6TD BOV adjustable?

[Dr. Diesel]

Stan,
Ditch that whole EGR setup immediately. Have a good look inside the intake manifold, and make sure it's not all carboned up inside. TDI's are NASTY for this problem, due to having an EGR system. I saw one where the inlet elbow diameter on top of the intake was reduced by 50% from carbon/soot buildup!! Perhaps the same deal has occured on your engine.

The coldstart knob should only be noticeable below ~2000 rpm. After that, the internal advance mechanism takes over.  If you notice a difference in power at any rpm (especially higher)  when you pull the CS knob out, then it's likely you're not getting any inj. advance at all. This happened to me last year, when I'd installed a pump with an "IN" banjo bolt on the "OUT" side of the injection pump. The car was a complete dog.

That turbo looks terrible too. If it's munched something, maybe it's axially rubbing on the scroll walls?  I'd wanna replace that if it was mine.

Dieseltech,
That's the same boost control system i've been using too! It's worked great since last fall. I'd monkied around with several other types with nowhere near the satisfaction of this system.

[andy2]

My guess is that the Garrett and KKK turbo's max boost is different if both were non wastegated and since the Garrett is capeable of higher psi this is what is happening ,I got the same results with the K24 as VWRacer. both as we know run the same stock psi but are totally different when modified

[VWRacer]

Okay, I'm making some progress!

I took Doc's advice and removed the EGR system completely. Here a photo with the blockoff plates in place. The intake plate is 1/8" aluminum. I reused the old undamaged gastket with orange high-temp RTV. I chopped off the exhaust-side elbow and made a crude 80-thou stainless blockoff plate. Both held very well!



The boost is still maxing out at 12 psi, but the smoke is nearly all gone - just a tiny bit as the engine hits the fuel limiter. Horsepower is back up, too. I did two back-to-back runs through 3rd and got 58 hp on each run. Up over 10 hp!

Someone mentioned that they couldn't get more than about 12 psi with the stock exhaust, so I took a look at the pipe on my car. The downpipe has a HUGE crimp right after the turbine section outlet! :cry:

The pipe appears to be a nominal 1.5" OD, but crimps down to about 1" right after the outlet.



This has got to have a big impact on boost production. I have some 2.5" elbows and bit and pieces to build a test system, and will get to it this week. Right now I gotta go do the family thing...back tomorrow night!

Cheers! Stan

[DieselsRcool]

Yeoww!

Stan. Are the blades totally trashed on your compressor wheel or is that just the photo? Looks pretty bad.

[VWRacer]

The leading edge of every other blade is pretty chewed up... :?

At least I don't see any sign of the compressor wheel touching the scroll housing.

[Dr. Diesel]

hey Stan, just for shizens and giggles, why not unclip the downpipe from the toilet bowl and take it up the street, Gtech on?

[DieselsRcool]

I'm no turbo expert but I think you need to take a closer look at your compressor wheel. I looks to me like something has gone into the turbo and damaged the wheel quite severely. It looks like about 3/8" of every other blade is missing. That thing must be very out of balance at the very least and could explode at any time. Check this pic of a good wheel showing that every other blade sticks out further than the adjoining ones. Also notice the part that's missing on yours is at a shallower pitch than the rest of the blade. I believe this is designed to bring the slow moving air up to speed without stalling the airflow. Without this part of the blades your compressor may be having a real problem working, kinda like starting out in third gear. You turbo is probably not getting up to speed and boost, maybe that's why is hasn't blown up yet.  :shock:

Course, I could be full of crap too. :lol:

[Dr. Diesel]

i vote full of crap!  :twisted:

oh wait, no that sounded like an intelligent point. hehe

I vote for buggered impeller! :wink:

[VWRacer]

Hey guys...I'm back from Holidays!

Yeah, I agree that the compressor wheel looks pretty well knackered.  :cry:

DieselsRcool, is that new looking one a spare that might be available?

[DieselsRcool]

Unfortunately no. I wish I had an extra wheel to help you out. I just happen to have one of my turbos apart for rebuild and took the shot for your ref. It may be best to pick up a used turbo rather than buying a new wheel.

There is one on ebay now. You could recoup some money by re-selling the manifolds. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2480111643&sspagename=STRK%3AMEWA%3AIT&rd=1

Larry

[fspGTD]

Stan - I always thought there was something "odd" about your intake manifold setup - with the 90 degree "el" on top!  (Usually, the quantum intake manifolds I've seen have a block-off plate on top and a straight inlet on the side - where in your case, it has EGR going into the side!

Well, looked in ETKA and it was verified there are 2 versions of the quantum intake, and yours has the EGR!  I did not know EGR was a possiblity on a 1.6lTD - so I learned something new from you!  (I wonder if it's a california-only kind of thing.)  Anyway, good job figuring that one out.  That compressor wheel does look kind of bad.  Looks like debris was making it's way past the air filter...  So, you've got a few things to try at this point: 1. widening out that restrictive exhaust (it sounds bad in your case!)  2. fixing the chewed-up compressor wheel (looks like maybe a bolt was rattling around in there, something too big to make it's way past the wheel.  Dinged up the sides of the compressor inducer bore as well, I see.)  3.  up the fuel level (can't remember if you've got an EGT gauge already.  Be weary of the EGT levels resulting from increasing the fueling without doing both #1 and #2 above first!  An intercooler sure doesn't hurt either but I'm sure you can safely take the fuel up quite a bit without intercooler, if you just get yourself that big exhaust and efficient comrpessor blades.)

Nice progress... keep up the good work and nice reporting job with the pictures keeping us in the loop!  

[fspGTD]

By the way Stan - nice looking blow off valve block-off plate too.  

[VWRacer]

By the way Stan - nice looking blow off valve block-off plate too.  

Yeah, sorry about the ugly workmanship. The round one I made on the mill and is a good close fit. The others I simply cut from scrap...the one on the intake manifold is plate aluminum. The odd looking one under the sawed-off EGR elbow is 80-thou stainless. Ugly...but effective. :oops:

[Dr. Diesel]

My guess is that the Garrett and KKK turbo's max boost is different if both were non wastegated and since the Garrett is capeable of higher psi this is what is happening

In experimentation, I've seen 28 psi with my k24. 32 with the N2O on. :wink: