[s-cars] overboost and recent move

[JC]

Martin -

First there seems some conflation (confusion) between 'compression' and
'boost' leaks here. "compression" = combustion chamber, "boost" =
pressurized intake tracts before the cylinders.  Totally different things.

IMO MBC is foolish as the AAN Motronic w/ good (and MRC = perfectly good)
software is 100% capable and expecting to control the boost via N75 at RS2
levels (and beyond frankly).
With the MBC (depending on how you have it rigged...) as well as with a
cranked WG spring, you are limiting it's ability to control the boost
properly which again - it is 100% capable of.

Yes you may HAVE corrected a lot of BOOST leaks w/ a rebuild.  IMO you need
to yank the MBC, turn the WG screw way back and see if the Motronic w/ MRC
software works properly. If it does you can probably edge the WG screw back
up again.  If your engine was buckled up properly all should be well.  If
you still have problems, then you'll need to look back at vacuum hoses and
MAF and various things but you'll have eliminated 2 spurious potential
sources of problem.

Then just toss the MBC to somebody w/ a Honda or an old 'dub or something...


JC

> -----Original Message-----
> From: s-car-list-bounces at audifans.com
> [mailto:s-car-list-bounces at audifans.com] On Behalf Of Martin
> Baggenstos
> Sent: Saturday, October 01, 2011 1:40 AM
> To: s-car-list at audifans.com
> Subject: [s-cars] overboost and recent move
>
> Hello Everyone,
>
>   I have two questions hopefully that can be answered. I just
> recently had my engine rebuilt in my 1995 S6 and has a 1.9
> spring in the wastegate and I had put a MBC (in series if I
> remember correctly or maybe parallel) to prevent overboost. I
> run MRC RS2 software. Since I have been driving my car with
> the new engine it is overboosting way to high. I had turned
> the screw down on the wastegate before. I was hoping to find
> some clarity to the overboost. My compression test in my old
> engine demonstrated a lot of leaks and maybe that is why when
> I had the WG screw turned down, I was not overboosting.
> Should I back the WG screw out all the way since I am
> assuming that my new engine is not leaking compression and is
> holding the boost much better. My other question is in
> regards to the manual boost controller that I have hooked up.
> Should I just get rid of it and relie on the N75 valve to do
> its job, but I had that the N75 valve is not fast enough to
> respond with higher boost applications.
>
> I just moved to portland oregon and I would be interested to
> know if anyone can recommended local mechanics who are good
> with urS6 cars and could do some custom tuning. Thanks.
>
> Martin
> _______________________________________________
> S-CAR-List mailing list
> http://audifans.com/mailman/listinfo/s-car-list
> http://www.audifans.com/kb/List_information
>
>
> __________ Information from ESET NOD32 Antivirus, version of
> virus signature database 6507 (20110930) __________
>
> The message was checked by ESET NOD32 Antivirus.
>
> http://www.eset.com
>
>


__________ Information from ESET NOD32 Antivirus, version of virus signature
database 6508 (20111001) __________

The message was checked by ESET NOD32 Antivirus.

http://www.eset.com