ELEVENS

I brought my car in for the GIAC performance software first thing Wednesday morning. It was a 90 minute drive to the nearest dealer. Unfortunately, things turned sour shortly after arriving. The tech said that GIAC doesn't have software for my specific ECU (2007 RS4). I asked if he would call GIAC to check, he said they don't answer their phone until 9:00 a.m. Kalifornia time (noon my time). So I asked to hang around and wait. So what was to be an hour appointment turned into an all day wait.

Well what do you know, once GIAC opened their shop, it was discovered that my flash wasn't on their server for some unknown reason, even though they claim to have flashed several cars with my same ECU. At any rate, the flash got done and the trip wasn't wasted, although my day sure was shot by that time.

The invoice was significantly more than what the shop quoted. The quote was $724.63, while I was charged $936.63. This was accounted for due to the "GIAC Spring Special" which included extras such as a hand held programmer and multiple tune files, stuff that I likely will never use.

The hand held program switcher allows selection of three modes - Valet (low power), Pump (91-93 octane), and Race (100+ octane). Also included is a "personal Firewall" which is a way to passcode-protect the switching of modes.

The software advertises 12HP and 8-10ft/lb gain. An increase in torque down low is definitely apparent. The accelerator pedal/throttle opening map has been greatly refined as well. These two characteristics are what make this software IMO. The car is easier to drive, easier to shift, and feels great. Lots of grunt, which was missing on this high-revving motor.

I've not had the chance to hook up VAG-COM and see what's going on, but my 3000-8000rpm 3rd-gear pulls have degraded significantly since the new flash. Before the flash, my car would always clock low to mid 8-second runs. I've made about a dozen runs over the past three days, and my best was only 8.9, while the others were in the low-to-mid 9 second range. It's baffling. Maybe VAG-COM will shed some light on it once I see what's going on with % throttle opening, torque numbers, and timing retard. I have a theory, I just need to see some VAG-COM numbers.

My car is stock other than the ECS Tuning H-pipe that replaces the resonator, and now the GIAC flash, of course. It's only been 5K miles since I did the carbon cleaning on the intake system. It has always run perfectly, and the GIAC tune makes it a much more enjoyable driving experience. It may be a cliche', but it really does feel like a whole different car off-idle to about 5K rpm.

Reggie

Thanks for the inputs. Let us know what you find out. BTW what happens with the S Button now on the mapping?

ELEVENS

That's a good question Reggie. I hit the "S" button a few times but I need more experience with it. I never was a fan of S-mode for two reasons: It makes the throttle even more unpredictably hyper active, and it raises noise. The extra noise was fine with the stock exhaust, but with the H-pipe, it's too loud for me (usually, unless I want to make a "statement"). I'll use it some more and let you know about the GIAC S-mode.

silverRS4

FYI- 3-8k times can really only be compared when the ambient conditions are practically identical. I have times for my car varying from 8.0 to 9.5 depending on temp/barometric conditions.

ELEVENS

Indeed. Sensitive little buggers they are. In this case, ambient temps were approx. 10 degrees warmer (55F). What's the cure for this?

silverRS4

B-L-O-W-E-R

The only way the sensitivity of the RS4 wouldn't bug me to death was if it had another 100whp on its worst day.

When I drove it to work every morning, I used to guess if my local sea level barometric pressure was above or below 30 inHg based on how the car behaved. I'd get to work and check the local weather station data, which updated every 10 minutes. After guessing correct 10 days in a row, I stopped. I used to crave high pressure systems like storm chasers seek out frontal boundaries in unstable Kansas air just so I could enjoy my car. Whipped I was, simply whipped. I've been sober for 5 months now.

Winterrunner

I agree, Ive had mine run almost 8 flat, all the way up to 9.2ish. The temp and humidity really make all the difference. On a cool (40ish) day with dry air, I can easily pull low 8's all day in the 3-8K timing.

silverRS4

Actually, its temp and barometric pressure that really make a difference. Humidity makes practically no difference, relatively speaking. People assume "humid" days are to blame for loss of engine performance only because they are almost always accompanied by hot weather, which is the primary offender. To compare (all else being equal for each example):

* A 50F increase in intake air temp results in a mass flow thats 9% less.

* A change in barometric pressure from 30.5 inHg to 29.5 inHg (the normal maximum swing in sea level pressure for most locations) results in a mass flow thats 4% less.

* A relative humidity increase from 30% to 95% results in a mass flow thats .6% less.

The RS4's twin ECU setup and constant wideband lambda control means the AFR is nearly perfect all the time under high-load scenarios. It also means that if ambient conditions are 5% worse on a particular day, the power output will be 5% less. The power delivery of the RS4 is also heavily related to a multitude of look-up tables that are load-dependant. Engine "load" is tied directly to mass flow. So as ambient conditions alter the peak power output, they are also effecting the peak load% seen by the ECU's and the character of the power delivery changes.

Winterrunner

Great info, I didn't know humidity had such a small factor.

ELEVENS

...and I thought Baro. pressure had a much bigger effect than just 4%. Go figure.