I believe the N52 was only 2.5L in North America....but in Europe they got the 3.0L. I have a friend in Europe that had a 3.0L in a Z4...and he said it was almost like an S54 in power character. (He has first hand experience with the M54, and S54) He loved it...but moved to a P car before the boost bug hit.
We got the 3.0L N52 in the US. I think stock it was about 260 crank hp but people have added bolt on mods to get closer to 290 crank hp. It does not have the high rpm capability and head flow and cams to get S54 power of 333 crank hp.
50 lbs difference
Dang, big difference!
If I got rid of my expensive steed speed twinscroll and expensive efr9180 and went to a boost logic and pt 6466, I could save 25 lbs and $1250.
4th gear
88mph
Rear tires break loose
I should be "testing" on a dyno...
^^^ I'm not going to try 140 on the street.....
My car will spin in these temps in 4th - if I haven't driven the car for a couple months (like now in winter) it really gets the heart juices flowing
That is the actual DBW throttle position.
The Throttle Pedal was at 100%
I was using a taper strategy to try to control boost creep.....that was an early run.
The more I tested, the more I refined the strategy eventually ending up on around 55% throttle to hold boost pressure to about 11 PSI.
The was as a result a drive pressure delta of about 5 PSI under load. (15 PSI back pressure, 11 PSI inlet manifold pressure)
Not an ideal way to control boost creep, but it was definitely worth the time to play with. (Really good learning experience)
The throttle goes from 90% to approx 10% and the manifold pressure stays at ~19psi, then drops to vacuum. Maybe there is a time delay on the transducer?
WOT
From when throttle starts to close, to when the inlet manifold goes into vacuum, it takes 0.154 seconds.
When the throttle arrived at 10%, to when the inlet manifold went into vacuum, it takes 0.077 seconds
Time for a human to respond to stimulus:
Visual = 0.250 Seconds
Audible = 0.170 Seconds
Touch = 0.150 seconds
From the drivers seat, I can confirm that I don't feel any delay in system response.
With the MS43 OEM ECU though....there definitely was a noticeable delay on the N/A car....and it seems to have gotten worse on newer cars. I drove my Brother's 2017 Audi S5 Sportback recently, and from when you lift off the throttle at WOT in first gear.....it takes nearly a second to stop accelerating!!!
Most modern strategies have "pillowy" tipout/dashpot features for driveline management and oxygen storage in the catalyst.
Yep, eeking out that last bit of emissions reductions during EPA test cycles has caused these double digit automatics with aggressive upshifting strategies and lazy throttle response. The only way mfgs get away with it is that the average consumer pays zero attention to their car as long as it cranks up and the radio works.
The first time I drove my car after converting it to standalone, the throttle response blew my mind. It made me realize that it's not the single TB that was the problem (major reason many people want ITBs) but the obscene damping that OEM control strategies have for drivability. It made my S52 more responsive than my S38 was.
Last edited by TheJuggernaut; 02-07-2018 at 11:16 AM.
I went back and looked at some logs from the drag strip.
The difference between when the throttle pedal (my foot) is 100%, and the DBW throttle is 100%, is on average 0.030 seconds.
There is a lot of "P" gain used by Motec to achieve this, with the DBW motor at 100% until target is reached, then over a period of 0.090 seconds it backs all the way down to about 20% DC to hold the throttle wide open.
I had my first M1 tuning experience on a GTR this past week, i was able to fumble my way around to get the car running decent, but def not a full tune by any means. That stuff is so sick. A little hard to navigate initially but its badass.
How much different are the firmwares compared to yours? Is it basically the same stuff, just with out the specific GTR can stuff?
328i Sedan Twin s366's, 6.0LS, TH400, MS3 Ultimate
9.20 at 150 on 22psi
They are different.
The GTR stuff has quite a few less areas of adjustability, because Motec has locked that stuff in.
Once you get used to the window structure though, it's pretty easy to navigate.
A big thing that Motec has going for it, is that EVERY single item has a help menu attached to it. (Just click on it, and hit F1) Then if you click on the highlighted subcategory on the bottom of that window, it takes you into a full scale user manual.
On my current custom package, I think I have 82 Tuning windows. (Drop-down tabs on the left) I probably use 10 of those on a regular basis though.....
To really get the most out of what Motec has put into this system, you really need to get on a load-bearing chassis dyno to tune the fuel film stuff.
Bookmarks