[urq] Reality Check (Dyno results) Follow up (long)

[Louis-Alain Richard]

Maurits,

> All this makes me wonder if the GV really has 200 BHP? The previous owner
>blew up his engine once (broken oil cooler lines) back in Œ88 and Audi ...
>Program rebuilded the complete engine, incl. new head, turbo, wastegate
>etc.

Yes, the GV is a 147 kW (200 hp) engine. Source is Euro-TFA.

>Worn valve guides OTOH, upset the air/fuel mixture and the gauge reading
>will be lower then normal and fluctuates rapidly in a range of 3². As the
>speed of the engine increases, the needle will steady.²
>My readings are 1² and yes, steady when increasing rpm, could this indicate
>premature wear of the valve guides?

IME, valve guide wear is a lot more unlikely than valve seat wear. And a bad
seat (or a broken valve) would act exactly like you describe.


I have 2 suggestions for you:

1- Check the timing marks for the t-belt: 6000 RPM max power is kinda high
for this engine (should be 5500 for a stock engine). Also max torque is 500
RPM too high. Maybe your cam is off-mark?

2- Then, unhook the exhaust system at the downpipe/cat-converter junction
and do it again.
That way, you'll rule out any plugged exhaust system.


You may want to do a couple of standard 0-100 km/h test (warm engine, cold
intercooler, minimal clutch slip, change gears at 5500 RPM) just to have a
baseline to compare the results. 
Standard Euro car was around 7 sec for 0-100 km/h (6.5 sec for 0-60 mph).
Poor us in North-America must wait until 8 secs for the same 0-60 mph.

HTH,

Louis-Alain
83 urQ, 


-----Message d'origine-----
De : urq-bounces at audifans.com [mailto:urq-bounces at audifans.com] De la part
de Maurits Jonkergouw
Envoyé : 31 mars 2004 09:29
À : urq at audifans.com
Objet : [urq] Reality Check (Dyno results) Follow up (long)

Hi, thanks everyone for their input.



I ran the IM test and there is 100% NO vacuum leak. I also checked vacuum on
the waste gate diaphragm and it holds 10² Hg forever.

I connected the gauge (Mityvac) to the IM vacuum port and run the engine at
idle, according the Mityvac manual it should read a steady 16-22² Hg with a
normal engine. 

Mine does 15-16² Hg when cold and later 16-17² Hg. NOTE: the needle
fluctuated very rapidly in the range of 1² all the time at idle. The manual
says it should be steady and does not mention such small movement, all it
does say is: 


But the manual also says: ³ Floating motion indicates (carburetor) too rich
or too lean.² I know my engine is running a tad rich, could this explain the
1² fluctuation?


Also, the manual says a low reading of vacuum pointer indicates late
ignition timing OR intake manifold air leak. In case of any leaks, the
needle will be about 3² to 9² Hg below normal but will remain steady, which
it does, but I¹ve checked the vacuum, and regarding timing, my ECU is of the
correct version (the Euro GV ECU uses a different map i.e. earlier than the
WR ECU¹s).

About 6 months ago the compression of all cylinders was 6.7 ~ 6.9 Bar. I
don¹t think it¹s changed much since, because it pulls better now then 6
months ago... Are these reading ok?


Perhaps the previous owner got scared and ordered to Œcut¹ the power by
decreasing the pressure of the WG spring. Fact is, the current boost
pressure is only 0.45 bar (absolute) and should be 0.8 bar if I¹m correct.

Last but not least: could the turbo loose 25% of power by age? I know it
doesn¹t smoke or has excessive play, the propellor blades are still in one
piece (checked). All it does is wistle quit heavily, maybe the air filter is
blocked? I¹m not using the original paper filter but the PiperCross OEM.
Could I accidentely reversed this filter and now blocking air? If it¹s
dirty, could this Œdirt¹ cut 25% of BHP?


Questions, questions and even more questions. I would like to thank you for
reading this, perhaps you could add some thoughts... Thanks.


Regards,
Maurits

'86 quattro GV (WR)
'85 coupe KV
'82 coupe DD