cahiil55k

I just got a login but I've lurked here for the past 5 months. So anyway, I took my stock '04 E55 to the dyno today so I could get some pre-upgrade baseline runs in. Out of 5 or 6 tries I couldn't really get a clean reading because Manual mode would not cooperate. The car still downshifted automatically from 3-1 and 4-2 many times and the only way to defeat the downshift was to mash the pedal at higher RPMs. Did we do something wrong or forget to set something? Looking through the forums, alot of folks here have successfully dyno'ed their cars within the rpm range of 2000-6000+, so help me out please. I will be returning to the same shop in a month after having some performance upgrades installed (VRP tune, pulleys, shorty headers, 80mm TB, heat spacers, cm30 pump, hi flow filters, coolant flush, new plugs) so any suggestions would be great. Here's what was done:

1) Hood open
2) "Sneaky ECU" reset
3) Dyno mode on
4) Shift mode "M"
5) Intake tubes removed
6) Manually shifted from 1st to 2nd to 3rd, waited for 35mph and also 40mph before gunning it
7) Manually shifted from 1 to 2 to 3 to 4, waited for 35mph and also 40mph before gunning it
8) Chevron 91 octane CA gas

The attached runs were done in 3rd gear on a DynoJet. From the looks of these inconclusive runs, I'm around 477hp/526tq stock at crank (18% drivetrain loss) but the tech said my a/f ratio are probably inaccurate except the fact that it's running too rich. Also, they could not get a boost reading - this didn't matter too much to me. Thanks.

OrionS55

I think you want to wait til you are over 3600 rpm and ease into the throttle to prevent downshifting.

AMGfan

+1...it happens pretty easily if someone isn't used to throttle...kickdown happened a lot on my dyno runs...they actually almost got to the point where kickdown wouldn't happen but by that time heat soak was pretty evident.

cahiil55k

Thanks for the replies. I was hoping manual mode would not allow an automatic downshift, which is what I read in a few other posts. Bummer. I'm going to play with manual mode a little more on the empty industrial streets here and will start around 3600RPMs in 3rd gear next time.

bassn_07

To prevent downshifting on the dyno I put a water bottle cap under the pedal to cover up the kick down button. It worked great!

shardul

iTrader: (1)

did you put the car in dyno mode?

cahiil55k

Yup we did. The ABS light was lit and the display read that it was in Dyno mode, so I think that means it was in Dyno mode. I'll try bassn_07's bottle cap suggestion after I drop off the wife at work.

izzyz28

I believe the ETC will still open the TB all the way when you press the pedal to the kickdown switch but don't actually press it. Car feels the same to me when it's all the way down or just against the switch. Next time I'm at the dragstrip I'll do a run against the switch and see.

Edit: Nevermind, I believe the trans will upshift earlier if you don't have it matted. I'll check tomorrow on the way to work.

bassn_07

Did you ever get it figured out?

cahiil55k

I haven't tested it out yet. I hit a nasty curb yesterday (city bus forced me into it) and ended up taking the car to a rim repair shop for curb rash removal. The car will be ready to test either tonight or tomorrow. I'll post the result here.