[s-cars] Sharp turn toward S-car info ahead! Warning!

[Steve Eiche]

Comments in text below.

Eric Phillips wrote:
>> Date: Sat, 28 Apr 2007 15:27:57 -0600
> Steve - I don't know about that, but I do have a couple of S-car
> software questions.
> 
> I have, right now, MRC Stage 2.  I have, in my Rossatobin, a nice RS2
> exhaust manifold, some good, used RS2 injectors, and have a line on a
> good, used RS2 turbo.  I could also buy a GT2871.  (Minor
> permutation).  I have heard several opinions on how to proceed from
> here, but I was wondering if you give me a little more info on some
> stuff.
> 
> 1.)  I'm going to install a Bosch 005 fuel pump this summer, and plan
> on using the stock fuel pressure regulator.  Will the software
> (whichever software gets used) know that the fueling is good all the
> way up to WOT?  I hear some software has WOT enrichment at WOT/high
> RPM to make up for fuel delivery problems under those conditions.

That all depends upon the condition fuel supply system of the car that 
the software was tuned for originally.  IMO, I don't think adding fuel 
to try to make up for a fuel delivery system that isn't up to snuff is a 
good idea.  Better to fix the fuel delivery issue or to limit output to 
a safe sustainable level. YP(philosophy)MV.

 From my data, the commonly available software out there for the RS2 
configuration will run within 5hp and 5lbsft of torque.  Testing was 
done with an RS2'd S6 with FMIC and RS2 components in Denver on a 
Superflow dyno.  Also IME, if you change from the RS2 injectors (say 
RCs, Lucas Delphi, etc.) and try to run generic RS2 software on your AAN 
your results will vary more widely, but generally will not be as good. 
As of yet, I haven't seen an injector that has the same flow 
characteristics as the RS2 injectors.  Note that I do NOT have 
experience with any of the new Bosch plastic body injectors which very 
well may work well.  There may also be software out there designed for 
specific injectors other than RS2s, but I don't have experience with 
that either.

Also IME, I would go with the RS2 turbo for durability's sake alone. 
You will give up a little performance to a Garrett perhaps, but it fits 
without any modifications and lasts forever.  The same cannot be said 
for Garrett turbos.  I know of several AAN that have used RS2 turbos for 
without any issues for over 100k miles.

> 2.)  How are the different software makers different in their
> philosophies on the RS2 level of power?
> 
> BTW:  keeping stock MAF and cams.

Not sure why you would ask me this.  I can only answer for myself, but I 
  did have "philosophical" discussions with Mihnea Cotet of MRC and 
Guenter Mandl of Sportec when they have been in the Denver area tuning 
cars.  Their philosophies, at least at the time we spoke, were quite 
different.  Mihnea's philosophy was to change as little as possible to 
get the desired output, and Guenter's was to tweak anything that would 
be affected by changes.  I don't believe Sportec offers any "generic 
RS2" AAN software.  The only Sportec AAN software that I know of is for 
a very specific set of components and running it with anything else will 
be very hit or miss.

As to what I would recommend, if you are satisfied with RS2 levels, go 
with whomever who feel most comfortable with.  If you are going beyond 
the plug and play RS2 configuration, do your homework and be prepared to 
spend some time and money to get custom dyno tuning done.  I've heard 
good things about Tony at EPL for this, YMMV.  If you plan on changing 
and experimenting a lot, you might as well go with an aftermarket 
injection system.  Personally, I would recommend 034EFI because they 
specialize in Audi injection systems so you don't have to reinvent the 
wheel to make some other system work.  Then you can play to your heart's 
content without going broke on paying for someone else to custom tune 
your car or have to deal with poor running and mixture adaptation codes, 
etc., when you change something.