head gasket failure - confirmed

[E. Roy Wendell IV]

On Aug 29, 2006, at 9:52 AM, tmb wrote:

>> I thought that something seemed familiar so I
>> dug in the archives and
>> confirmed that you are indeed the person who
>> upped their boost by
>> defeating the ecu safety by way of the zener
>> diode despite the
>> collective wisdom of the list telling you it
>> was a bad idea. Not two
>> weeks or so later you suffer a head gasket
>> failure. Coincidence? I
>> think not.
>
> see that.  i like to call that an "assumption".
Well, since we're going tit for tat......
I did not assume one way or another, that's why I asked about the  
fire rings. I simply put together cause and effect and thought it  
might apply. You seem so convinced that it was an installation error  
and I was simply pointing out that it may not have been. Devil's  
advocate if you will but it beats replacing head gaskets for the  
wrong reason. It has been my experience that head gaskets are pretty  
fool proof if they are the correct part, the surfaces are clean, and  
the bolts are torqued correctly.
>
> i recall you from way back in february when i
> started trying to get my head around some of the
> type44s design strengths and flaws.  you were the
> one that accused me of being ricey and attacked
> me for wanting to lower my car.
Because ten out of ten suspension engineers agree that an excessively  
low car is dangerous on the street especially if the suspension on  
said car isn't redesigned for the new ride height. I did not have a  
problem with you wanting to lower your car, rather I had a problem  
with you wanting it lower than what H&R springs would accomplish.  
H&Rs are pretty damn low. Radical changes in ride height accomplished  
by only changing springs is just poor practice by any standard and I  
stand by that statement. It was not an attack. You asked and I  
answered and we don't agree.
>
> of the many things that were said in your email
> reply to me, you said that you reserved the right
> to laugh at me when bad things happened to me.
> well, bad things have happened to me, and they've
> not been because i just jumped the gun and upped
> the boost.  it was done in such a way that fuel
> and air in proper measure were present at all
> times.
I may have been somewhat out of line when I said that but as I recall  
you'd already poked me with a stick pretty good by the time I made  
that statement. Sorry I didn't rise above it but I stand by the  
technical aspects of the argument.

As for your claims that your AFR was correct at all times I would  
have to say that unless you have a dyno plot showing showing as much,  
your claim is unsubstantiated. I speak from personal experience here.  
I too thought I was in like Flynn and drove around for a year  
oblivious to the fact that my AFR was going to 17:1 at times. I knew  
something was up when after the dyno pull the operator called his  
buddy over and said "Check this out!". Those two are still wondering  
how the hell it held together. What they didn't know about was the  
incident not too far in the past where I had a head gasket missing  
the fire ring between two cylinders and a quarter inch wide hunk of  
metal missing out of the head in the area of the gasket failure.
>
> i did NOT do the zener diode mod.  i asked about
> it, and while i managed to get the resistors, i
> still have yet to get a 4.3V zener diode.  it

> sounds like a very good way of getting power, and
> i'm sure that it would have worked fine.
> however, i went another route.  check the
> archives.  i made mention of it before.
I find only mention of an "ECU and spring mod" which could include  
the zener/resistor trick as it requires soldering inside the ECU. I  
didn't find any talk of QLCC or SJM so what conclusion other than  
zener/resistor mod was I to make? I did find posts that indicate your  
complete ignorance of how the stock 10V turbo boost control system  
works. At the very least you should have read every page on the SJM  
Autotechnik site a few times over. I doubt that anyone on this list  
knows the ins and outs of the 10V turbo fuel and ignition system as  
well as Scott Mockry. Also, you are mentioning some pretty high boost  
levels. As far as I am aware, none of the common chips are rated  
higher than 1.8 bar absolute or 11 psi gauge of boost. You talk of 16  
psi and higher. So what are you running?

As an aside, until you get past 2/3rds throttle and activate the full  
throttle switch the ECU is running in closed loop mode. The ECU in  
conjunction with the O2 sensor will keep the AFR at 14.1. By  
installing a stiffer wastegate spring you are running a  
stoichiometric AFR at considerably more that the 1.1 bar for which  
the entire engine was designed for. Full throttle dyno runs don't  
show the whole story. You may be doing more damage at part throttle  
than at full throttle.
>
> a friend of mine has been a vw/audi mechanic for
> about 25 years now, and had much luck tuning the
> 10VTs back in the late 80s and early 90s.  my
> digital gauge showed me that it was putting out
> 2.0BAR of boost, with some peaks at 2.1BAR before
> the head gasket failed completely.
>
> he drove his test car for 250,000km with the same
> mods that i have in mine.  never ever did his
> head gasket fail.  the car was eventually
> scrapped because it rusted away.  i trust his
> judgement implicitly because he has proven his
> knowledge time and time again to me and to his
> many loyal customers.
You've used this example before. Here's the problem: The car you  
reference is a 5000tq with an MC1 motor that has lower compression,  
different cam, different turbo, different airflow meter assembly, and  
a different fuel metering head than your MC2 motor. Not an apples and  
oranges comparison per se but certainly different varieties of apple.
>
>> A blown head gasket if the first
>> symptom of an engine
>> experiencing detonation. Any chance one or more
>> of the fire rings on
>> the removed head gasket is distorted?
>
> the head gasket gave out where the head was
> marred during it's reinstallation.  while a total
> PITA, it's an understandable occurence because of
> the weight and awkwardness of both the head
> assembly, and the small area that it needs to be
> fed into.
>
> the cheque was in the mail on this one.  if 2
> days @ 19psi didn't do it, then 30 days at 8psi
> probably would have.
>
>> As for installation of the new gasket, what you
>> really need is tool
>> number 3450 seen here:
>> http://www.zelenda.com/VW/page3.html
>> It's an allen headed stud that screws into the
>> block in place of a
>> head bolt and has a head that's  just the right
>> size to fit the
>> oversized holes in the head gasket and head.
>> Once you have everything
>> clamped in place by snugging down a few of the
>> head bolts you then
>> remove the stud using the special allen driver
>> included in the tool
>> kit. Without it there's really no way to make
>> sure that the head
>> gasket is centered around all the cylinders.
>
> i sincerely thank you for this information.
> however, my ARP studs are on their way, so i
> think that this tool will not be necessary.
>
> here's the thing, i'm here for information.  i
> want to learn.  i want to know how large of a
> smile a 10VT can paint on my mug.  if you can
> offer info, then i thank you.
>
> however, if you feel the need to preface you help
> with pointless attacks on me, then please don't
> bother.  i have been more than civil the first
> time you attacked me, and now this time.  do we
> need to do this again?
>
> jason
> tmb
What you fail to realize is that this is a public forum and while I  
reply to your questions I'm not writing solely for your benefit. I  
feel it is my duty to point out the possible pitfalls of your course  
of action for the many others who read this list so that they can  
make informed choices. The risks you are willing to take with your  
equipment may not be the same as others are willing to take. If you  
have great success than you are certainly free to shout about it from  
on top the mountain.
Once again, what this boils down to is a difference in attitude. I  
consider myself just smart enough to be dangerous. I'm smart enough  
to know that I'm not that smart. I listen to others very carefully  
and learn from their mistakes. I don't think that Audi engineers are  
a bunch of idiots outside of their omission of an accessory position  
on the ignition switch so that the lights and radio turn off with the  
key. They designed an engine and management system that is meant to  
work a certain way and there is no avoiding the simple physics that  
dictate that running it outside the design parameters has certain risks.

Roy Wendell
erwendell at mac.com
Too many type 44 tq
A pair of MR2s