[BiturboS4] Blown turbos

[Edwards, Dave]

Well Ti,
I'm glad it was you who suggested that some of the US car faults may be due
to US driving style and not me!

On the subject of turbo reliability, I've noticed since I had the full
Miltek exhaust system installed, my oil temp is on average about 10 degrees
lower than before. Seems that now the turbos work less to produce more!

I notice that you're getting a new 1.8T A4 soon. I drove one recently and
was disappointed in the engine. Initially I thought it was a diesel!!! I
then drove a Skoda Octavia (I don't know if you have that in the US - its
another car from the VAG group, based on the Passat). Apart from the general
quality and comfort being a lot worse than the Audi (but that's OK at nearly
half the price!), I thought the engine was far superior to the A4's. I don't
know how much of the engine is the same, but the Octavia's is 1.8T 5V.

Cheers,
Dave

-----Original Message-----
From: Ti Kan [mailto:ti at amb.org]
Sent: 05 September 2002 09:49
To: Dave_Edwards at iOra.com
Cc: cfields72 at hotmail.com; biturbos4 at audifans.com
Subject: Re: [BiturboS4] Blown turbos


Edwards, Dave writes:
> I have read a number of posts from Americans about hearing a
> 'siren-like' noise, and some replies saying that its normal. All I can
> say is that over here we don't have any reports of such a noise. Just
> maybe there is a difference between US and Euro S4 which means the
> turbo is noisier for the US car, but I can't think why.

There is no difference between US and Euro S4 as far as the turbos
themselves go.  The number of reports of noisy US turbos is simply a matter
of a majority of S4s on these forums being in the US.  When you have more
people from one group, you're going to hear more from them, and those with
problems are going to be the most vocal.

I have a US S4 and the turbos are nice and quiet just as you described in
your previous post.  A little whistle that's audible with the window open at
low revs and quickly fades to inaudibility past 3K rpms or so.

> The S4 clutch should be fine for a stage I or II upgrade. Having said
> that with the reports of clutch problems on this list, maybe Audi has
> used a substandard part in the US model? I have not read any reports
> of early clutch failure on Euro S4s.

Here we go again.  No, there is no difference between US and Euro clutches.

Where there are differences between a US and a Euro spec car, it's related
to safety, emissions and other regulatory compliance, as well as fuel
quality and expected operating conditions.  Audi does not use different
parts between the US and Euro models in a gratuitous manner, that would
increase cost where it's unnecessary.

Another factor to ponder may be the driving style.  Many US drivers like to
go from stoplight to stoplight with jackrabbit start acceleration. While the
S4 could do that just fine, this amounts to clutch abuse if the driver is
ham-fisted (ham footed?).  Perhaps this might explain the problems with the
turbos and other intake system woes with all those sudden spikes of boost
and vacuum.  Where European city streets are often narrow and crowded, the
driving style would no doubt be quite different. Where the S4 really shines
in Europe is when it stretches its legs flat out on the open highway.

-Ti
2003 A4 1.8T multitronic (soon)
2001 S4 2.7T
1984 5000S turbo
1980 4000 2.0
--
    ///  Ti Kan                Vorsprung durch Technik
   ///   AMB Laboratories, Sunnyvale, CA. USA
  ///    ti at amb.org
 //////  http://www.amb.org/ti/
///