[usc335]

This is part 3 of my original PROcede Boost vs. RPM Curves threads located here:
http://www.e90post.com/forums/showthread.php?t=237085
http://www.e90post.com/forums/showthread.php?t=255602

This time, I’ve graphed
(a) Boost vs. RPM and
(b) Actual Timing vs. RPM overlayed with actual (drive-by-wire DBW) throttle, “DME” Timing, and Air Inlet Temperature

The test conditions were: 91 octane | Temp = 80 F (and rising) | Altitude = 275 ft | DP-Back Exhaust | AFE DCI | RR Intake Scoops.

I did 4 third gear pulls with about 2-3 min in-between each run at default (70%) User Torque (UT). I did a 5th run at UT 60% with a few first and second gear pulls before the third gear pull to get the car to adapt. All runs were done with 100% ignition correction.

(1) Here is Boost/DBW Throttle vs. RPM for Default UT (70%):


(2) Here is Boost vs. RPM for Default UT (70%) and UT 60%:


(3) Here is Boost vs. RPM for Comparing the 2-19, 4-22, and 7-29 Maps:


Observations:
(i) The “actual” manifold boost pressure is probably about 0.5 psi lower than shown on these “intercooler charge pipe” datalogs. I’m basing this off of my boost gauge.
(ii) Although I did not show this graph, I overlayed the boost curves for the first 4 runs and the boost was very consistent – the graphs were right on top of each other.
(iii) Dropping the User Torque by 10 points (10%), lowered the boost by about 0.5 psi.
(iv) Boost on the 7-29 Canbus map is lower in the midrange than before (probably due to an increase in fuel pressure that I think Shiv mentioned).

See 2nd post for timing curves.

[usc335]

Here are the Actual Timing vs. RPM overlayed with actual (drive-by-wire DBW) throttle, “DME” Timing, and Air Inlet Temperature for Runs 1 through 5 (I started graphing when I went WOT):






Here is an overlay of the DME Timing from Run 1 with the Actual Timing from Runs 1-5:


Observations:
*** Sorry, but I didn’t start the pulls at the same rpm each time (it was intentional on the 4th pull).
(i) I need an aftermarket intercooler as the IAT increase is ridiculous.
(ii) The IAT idling was ~130 F (50 F above ambient), while the IAT cruising at about 30 mph was ~115 F (35 F above ambient). The temps actually drop quickly once you start moving. I didn’t check it crusing at higher speeds.
(iii) The timing drop at about 4500 is very consistent and probably due to the vanos shift.
(iv) The timing curves from about 4500 to redline are remarkably consistent. The actual timing does not creep up to the DME Timing of the first run. So, the theory of timing being adapted out is false (at least above 4500 rpm).
(v) The timing curve on Run 1 looks great, but the other timing curves (at least below 4500 rpm) have timing drops. I’m not sure if that’s indicative of knock or not. Run 4 “shows” knock at ~4400 rpm and Run 5 shows knock at 2600 rpm (just after I went WOT). Runs 3 and 5 are the only ones where the actual timing just about equals DME timing, but ONLY very specifically at ~3500 rpm followed by a timing drop (due to possible knock detection?). I have some theories as to what is happening below 4500 rpm, but I’d like comments from other PROcede users. Other than the first run, below 4500 rpm it looks like the DME is aggressively trying to add timing (even though the procede is reducing it) resulting in knock??? (See Post #8 for some more of my thoughts).
PLEASE READ THIS: I’d like to keep this thread PROcede related. Please do not turn this into a tuner war. If you do not have anything constructive to say, please keep it to yourself. Thank you.

[discostick]

It looks like you are getting pretty bad knock at 4500rpm where boost increases, also at lower RPM it is all over the place? According to the guide you should lower UT.

Did you do any logs at 0% ignition correction? That would be interesting to compare whether the knock was better, worse, or the same. Your timing from 4500rpm up is around 5 degrees, so if it is much higher, like 9 degrees with 0% ignition correction that would prove timing was being altered. If it was still at 5 degrees that would prove it was not being altered.

[usc335]

Originally Posted by discostick

It looks like you are getting pretty bad knock at 4500rpm where boost increases, also at lower RPM it is all over the place? According to the guide you should lower UT.

Did you do any logs at 0% ignition correction? That would be interesting to compare whether the knock was better, worse, or the same. Your timing from 4500rpm up is around 5 degrees, so if it is much higher, like 9 degrees with 0% ignition correction that would prove timing was being altered. If it was still at 5 degrees that would prove it was not being altered.

I didn't do any 0% ignition correction runs/logs (all were done at 100% ignition correction). I lowered the UT to 60% in the last run and it didn't seem to help. If, in fact, I need to lower the UT even more that would seem strange to me since my car has the requisite mods for Stage 1 and it wasn't THAT hot outside...

[Joshboody]

my 335 is stock, so I don't have first hand experience. but looks like you you need to customize the timing map... which is posible with proceed correct? This looks like you are bouncing off the knock sensor, and this is stage 1 map at 100%... that's very surprising!

I would love to see timing versus rpm with a flash... anyone know if this data exists?

[usc335]

Added to second post: Other than the first run, below 4500 rpm it looks like the DME is aggressively trying to add timing (even though the procede is reducing it) resulting in knock???

[Kelvin1000]

Naah, the Vanos Cam change event always occurs there (even on stock form). The timing looks good!

[usc335]

Originally Posted by Kelvin1000

Naah, the Vanos Cam change event always occurs there (even on stock form). The timing looks good!

Here's what I think is happening by run:
(1) Run 1 - Looks ideal.
(2) Run 2 - Timing drops just after WOT then climbs to where Run 1 was. Looks okay.
(3) Run 3 - Timing drops just after WOT then climbs higher than Run 1 before starting to taper off at the vanos switchover at ~4500 rpm (It's not a sudden drop off). It's interesting that it increased timing by 2 degrees between 3300-4300 rpm.
(4) Run 4 - Timing drops just after WOT then climbs to where Run 1 was, then drops at ~4500 rpm just like Run 1. Looks okay.
(5) Run 5 - Timing drops just after WOT then climbs rapidly before a sudden drop-off at 350 rpm, then climbs normally, then drops at ~4500 rpm. Oddly enough, this is the only one that looks like knock to me and this is the one where UT was reduced! Is it becuse the UT was reduced that the DME was trying to add timing back in aggressively?
(6) Again, above 4500 rpm, the timing in every run is very consistent. But, below 4500 rpm, it seems as if the DME may be getting more and more aggressive with the timing until it finally knocked in run 5?
Any comments on all this? Thanks.

[Joshboody]

Can you clarify the "Vanos event"? At 4500 is the intake valve closing sooner, thus more cylinder pressure and more timing retard needed?

With Vanos, the same cam lobs are used correct? so same valve open/close durations but at different times? Intake and exhaust cams are not a direct link through vanos, but can be adjusted independently? Or when 1 is altered the other is also by same degree?

sorry tough to find detailed info on this stuff.

[TheTwinz]

wish I could help, or even understand those logs, but where's all the support from the regular folks? shiv? jpsimon? those that know or have posted their logs before should be able to determine whats going on since they are expert log posters.

[usc335]

Added item 6 to Post #8.

[dcafs]

From what I see, most of your timing dips correspond to the throttle plate closing.

So your DME is reacting to something. Question is whether it is knock or some other condition.

I noticed this pattern on some of my datalogs as well and found that the event that seemed to be causing throttle closure and timing pull for me was missed boost targeting (ie actual boost pressure was exceeding targets).

If you have the BT tool, you can log actual boost versus targeted boost. Almost every time boost goes overtarget, the DME will close the throttle plate to compensate and bring it back down.

If you correlate the boost target data to these graphs by rpm point, you should be able to narrow down the underlying reason for these timing spikes.

They may not be reacting to engine knock but rather to missed boost targets.

Something to consider!

[usc335]

Originally Posted by dcafs

From what I see, most of your timing dips correspond to the throttle plate closing.

So your DME is reacting to something. Question is whether it is knock or some other condition.

I noticed this pattern on some of my datalogs as well and found that the event that seemed to be causing throttle closure and timing pull for me was missed boost targeting (ie actual boost pressure was exceeding targets).

If you have the BT tool, you can log actual boost versus targeted boost. Almost every time boost goes overtarget, the DME will close the throttle plate to compensate and bring it back down.

If you correlate the boost target data to these graphs by rpm point, you should be able to narrow down the underlying reason for these timing spikes.

They may not be reacting to engine knock but rather to missed boost targets.

Something to consider!

Interesting theory. Thanks for the info. I'm sharing a BT Tool with someone, so I'll have to get it and do some more logs.