Date: Wed, 20 Jul 94 12:19:44 EST
Subject: UrQ Cylinder Head Odyssey, Part I

OK, OK, time for me to put together the DefinitiveAnswerToDate(tm). If
the car actually runs again someday, I'll report on it then . . .

   > Well, the nice shiny new ported'n'polished head was about to be in-
   ...
   Tell me what you did to your head!  I just heard back from Sport Wheels,
   and the verdict is that my old ABT head probably can't be salvaged.  Looks
   like I'll need a new one... ka-CHING$$$.  I was thinking about a hydraulic;
   heard of anybody updating?  Did you have your new head extrude honed, or
   did they port it by hand?  How does it look?  How much did it cost 'ya?
   Did you have the head shop put in the bigger 40mm intake valves?  Did you
   have the intake manifold match ported to your head?

I eventually came up with three "viable" options on the '83 UrQ cylinder
head. By "viable", I mean parts/components/assemblies actually allegedly
exist, and even have a known price tag, etc., and so forth.

Option one: Shokan has "modified" 5-cyl turbo heads for $500 (it was
either $495 or $595, I misremember which, but since nothing for an Audi
ever costs less than $500...). The guy there *assured* me that the modi-
fied (to hydraulic lifters) head will bolt right on, and is 100% compa-
tible with the TurboQuattroCoupe engine, they've "done it before with
no problems", etc. and so forth. Very VERY tempting. New York, so ship-
ping to Mass is not only not expensive, but probably second day delivery
as well! The head is complete (I assumed no cam...) and ready to install.
But used . . . so probaby has the stupid little "can be ignored" cracks
'twixt the valve seats . . . And at least one other "Audiite" (called so
many, they're all a hazy blur) also said absolutely NOWAY/the TQC engine
was different/5000 Turbo head will NOT work ever at all! So ???  Caveat
Emptor as they say.

Option two: EuroPart claims to have in stock TQC heads complete (again,
I assume no cam, injectors, etc.) for $1350. They may or may not be "big
valve" heads. They may or may not have other [ABT??] "big valve" heads
for the TQC engine. They do have lots of stuff for the TQC (ABT cams,
bigger intercoolers, "normal" stuff like pistons, injectors, etc.) as
well. Seem to know their stuff.

Option three: New Audi head. My olde heade was part number 035 103 373G,
which is listed by Audi as superseded by 035 103 351BC, which Linda at
Carlsen quoted around $650 for bare head. Figure another $500-$700 for
valves/et al., say $1200-$1300 ballpark "complete", depending on what
sort of deal you can work on valves, springs, etc. Cheaper of course if
you "reuse" the old valves/springs/etc. Very dubious proposition for the
exhaust valves (so I am told), although feasible even typically-OK for
the intake valves, if they are still in good condition. [Aside: do not
NOT *NOT* EVER "grind" the valves, they have a "stellite" (?? or some
such rare "unobtanium") surface which grinding will remove/destroy;
"grinding" not to be confused with "lapping"...] Springs ??? Again, it
depends on their condition...

I ended up choosing option three, although had EuroPart bothered to re-
turn any of my multiple phone calls a month ago I probably would opt for
their $1350 deal. Largely I was "afraid" of the Shokan deal - unknown his-
tory of the head, somewhat nervous about the "true compatibility" of the
head, will it suffer the stress of subsequent "performance enhancements"
gracefully? Etc.

As it turned out, the local dealer (Pass Weitz [sp?]) actually had the
head in stock, and my mechanic browbeat their parts department into sel-
ling it to me for $700 delivered "today". New valves all around (the ex-
act wording was filtered through my mechanic, but to the effect of: "Some
Fucking Moron Ground Your Valves And Ruined The Lot" -- that's how I know
about not grinding Audi Turbo valves...). New "competition" (or "sport")
valve springs ("you'll need 'em if you ever want to put in a cam" ["Uh,
doesn't it already have a cam?" "No, a CAM!"] :-). I'm keeping the stock
cam for the nonce (I want to see what change effects what, minimize the
number of variables, etc.).

And, as long as I was doing a new head anyways, I had it ported'n'polished
by "Dick" at SRS in Walpole, who was highly recommended to me by my mecha-
nic ("He does *my* racing engines/heads"). Since I am far more interested
in low-end grunt than high-end peak power [Hey! there just aren't that
many places around here where I can safely pull 150mph! And there are
zillions of Toyota Camrys who seem to delight in lurking at traffic lights
just so that they can out-drag me off the line and block me into traffic!],
the actual "polish" is fairly minor. Dick nicely matched the manifold ports
to the head, and did some significant (most of, in fact) work right around
the valve/stem/seats; cleaned up all the flash; reshaped/tapered the guide
and mouth area around the valves; "five-angle-grind" (??) on the seats, and
so forth. I specified "street" "reliable" over "peak power" "racing", so
he didn't "polish" very much. (A real "polish", much as it may help the
peak air flow, actually hurts low end a little in that there can be so lit-
tle turbulence that the gas/air doesn't mix well resulting in poor street
idle/performance.) I figure that I am looking at around two grand for the
head "complete". Both "Dick" and "Dave" (my mechanic) assure me that with
the new head in place, I will have better low end response than the old
head gave me, as well as improved top-end. Oh yeah, I also opted for the
adjustable cam gear so I can play around with advance/retard of the
whole cam, see what effect that has on low/top end... (Yeah, I'm a toy
junkie, I admit it)

No, I don't know yet, the head is not yet installed! As Dave was cleaning
up the block preparatory to installing the new head, he noticed "something
odd" about the #3 piston. Pulled it, and it's damaged. Not badly, but it
clearly contacted "something", and scuffed itself a fair amount. The top
compression ring is nice and mirror-polished for about 95% of its circum-
ference, but at one end is clearly heat-burnished (you know, that nice
color-hardened reddish/bluish/black that can be so attractive on a fine
firearm, but really *SUCKS* on a piston ring!), and has lost much of its
spring/tension. #4 piston has slight scuffing just apparent, but nothing
really bad (#4 was where the cylinder head cracked). Dave surmises that
the engine got SERIOUSLY overheated at some point, maybe even to the
point of some serious detonation, and probably ate -- or, at the least,
mangled -- some valves; and the previous owner had some quack mechanic
"fix it" (grind the valves, ignore -- or not even notice -- the pistons),
toss it back together and dump it. #1/2/5 pistons were "mint", and all of
the cylinder walls were "perfect", so it was only one piston that was
really hurt. So, anyways, a new set pistons are on their way (A whole Set?
I hear you say... yeah, it was cheaper than buying just two pistons! I
guess the parts guy was tired of stocking them...)

So maybe this weekend I will have a running car again. Or maybe not. Who
knows . . .

   Well, didn't you know that UR stands for Un-Reliable?

No, actually, I didn't. Live and learn.

   P.S., doesn't your new water cooled turbo help with the low end?

Not significantly. While it's been a month since I've seen the car
running, as I recall that with the new "S4" turbo it will actually build
up a PSI or two as low as 1800rpm, and is on full 11PSI boost by 2500,
it's (well, was, anyways, we'll see how much the new head helps) still
a dog till 3000, where it wakes up ("comes on the cam") and takes off,
where it pulls strongly until it cracks its head . . .

   There is a euro 81 TQC which has a rebuilt  engine like you are thinking of.
   Not sure
   what the actual story is with the engine, but it broke and was rebuilt using
   coupe GT pistons with higher compression and slightly larger bore. I am not
   sure what was all
   done to make it work, but we hear that this car is really goes. With the
   euro camshaft
   and the increased engine capacity, it has some good low end torque. They
   didn't have to worry about increasing the fuel quantity because the early
   euro cars run
   open loop, dumping in all the fuel it can, all the time. No O2 sensor or cat
   here. This
   car currently has piston slap on the #5 cylinder and is looking toward
   another rebuild.

I wonder if the "mere coupe GT" pistons are not strong enough for the
stress of a Turbo engine? I was impressed how "clean" (after soaking in
cleaner for awhile...) my pistons are after 100K miles. Look almost new,
except for that #3 bugger...

I opted out of a "whole rebuild"/pull the engine/overbore/stroke it/and
so on. I don't know quite how I am going to pay for the work currently
being done (OK, I know which Plastic will pay for the work; I don't know
how I'm going to pay off the bank that backs the plastic...eventually, I
guess...sigh)

   Then there is always that 91 20V turbo engine sitting at Shokan just waiting
   to be
   transplanted...

Had I realized back in November how much time/grief/money this was going
to accumulate, it might be easier to re-wire/re-plumb for a 20V engine (or
even better the S4 engine! DROOL! SLOBBER!). Probably not cheaper.

Off hand, how much did they want for the 20V Turbo motor?

Just fantasizing.

                                        -RDH