engine resonance/noise

["Colin Barfoot" <Colin_Barfoot@email.msn.com>]

Q list,

On my "new" 1989 200 quattro (MC) (I've had it now for 2 months) at about
3000RPM under load the engine gets very loud it seems loudest up to about
3200 RPM but is still muchlouder all the way to redline than my 1986 MC
quattro.

If I let off the accelerator the engine quites down.  It can't be exhaust
sincethe engine is quite underload at other engine speeds (and my 86 doesn't
even have the rear muffler- just a 3" SS pipe).

I'm concerned that this plus the high oil consumption 1L in 2000 -2500 km
(1200-1500miles) (as measured by the last few top-ups) is pointing towards
serious engine problems in my future.

Does anyone have any btdt advice or specific areas I could ask my mechanic
to check?

If i need to rebuild the bottom end and head how much am I looking at?  If
it is a high probability i could make the 86 a parts donor and use its
engine (which doesn't burn any oil and seems much stronger even at lower
boost).   (of course I could always plan to make a LT1Q (LT1 CD quattro in
Canada).

Thanks in advance for your assistance.

Colin Barfoot
86 5000 CDquattro 355,000 km (old family car and sometime autocross winner)
89 200 quattro 275,000 km (new family car)
90 Corrado G60 177,000 km (autocross car and wifeand kids city car)