First PocketLOGGER Datalog... advice??

95CarbonEclipse · 12-13-2007, 11:37 PM

So, here she is. This log is of a 1st gear launch and continues through til the end of 3rd gear. What kind of things should I be looking for? Anything strange showing up in here? Is that 'knock' at Time: 14:05?? Any advice would be much appreciated.

Thanks

turbolarry · 12-14-2007, 01:57 AM

Log only RPM's, timing, TPS, and front O2 sensor (O2 1). You don't need time or fuel trims.
Also, do a third gear pull; WOT in third gear from about 2500 to 7000 RPM's. No shifting, no letting up, floor it all the way. Log that and post.

GoldÐiamond · 12-14-2007, 12:14 PM

Really don't mean to hijack your thread, but can you please reply or PM me how you uploaded your log and what kind of PDA you used?

I have a PALM m105 and I can't figure it out.

romeen · 12-14-2007, 12:36 PM

Quote:

Originally Posted by GoldÐiamond

Really don't mean to hijack your thread, but can you please reply or PM me how you uploaded your log and what kind of PDA you used?

Ditto.

matthewdesigns · 12-14-2007, 12:38 PM

Quote:

Originally Posted by 95CarbonEclipse

So, here she is. This log is of a 1st gear launch and continues through til the end of 3rd gear. What kind of things should I be looking for? Anything strange showing up in here? Is that 'knock' at Time: 14:05?? Any advice would be much appreciated.

Thanks

Could be knock, but until you post a 3rd gear pull as suggested by turbolarry, there's not really enough to go on. We need more data points.

I'd suggest tossing out the TPS after verifying that it's good...no need to always log that value, as long as you know your foot is on the floor thereafter. Instead, I'd log airflow. That way you can get a handle on which timing map you are on, which will answer potential questions about higher RPM timing numbers. I personally get good, usable results by logging only RPM, Timing, and Airflow.

snowborder714 · 12-14-2007, 12:52 PM

Quote:

Originally Posted by GoldÐiamond

Really don't mean to hijack your thread, but can you please reply or PM me how you uploaded your log and what kind of PDA you used?

I have a PALM m105 and I can't figure it out.

Quote:

Originally Posted by romeen

Ditto.

He posted that log by taking a screenshot.

Here's a tech article on how to post a log:
How to post logs so that people can actually read them.

What software are you both using?

romeen · 12-14-2007, 12:54 PM

I'm using Pocketlogger.

snowborder714 · 12-14-2007, 01:04 PM

What it looks like the OP did was to use the info from this link - Viewing Logs on a PC - and then just take a screenshot with the log opened in the PLViewer.

romeen · 12-14-2007, 01:16 PM

Quote:

Originally Posted by snowborder714

What it looks like the OP did was to use the info from this link - Viewing Logs on a PC - and then just take a screenshot with the log opened in the PLViewer.

Thanks Brian.

I'm going to play around with that a bit.

95CarbonEclipse · 12-15-2007, 01:53 PM

Yea, I just took a screen shot of the data view in PLviewer. I'm going to go out right now and log 2 - 3rd gear pulls. One with the TPS and the other with the airflow. I'll post back in a bit.

95CarbonEclipse · 12-15-2007, 02:44 PM

Okay, here's both logs: (Time and O2 Trim are logged automatically apparently). Not sure if it's a factor but, for the record, my car was up to operating temp and Intake air temp ranged from 39* - 46*

Again, thanks for taking the time to view these.

matthewdesigns · 12-15-2007, 03:43 PM

Those look pretty solid...a lot like mine.

You do drop a little timing on the top end, though. Probably lean knock, but could be that you are jumping back to a higher timing map (although your posted airflow vs. rpm numbers don't suggest that). I wouldn't worry too much about that, as I would guess that you aren't seeing much time at 7K, especially given that the E3 falls off a bit above 6.5K...at least mine does (I'm usually shifting at 6500). There's a big gap b/t 6100 & 6700 in the second pull...I'm interested in knowing what's going on there, as you could be bouncing around a little (timing wise). Chances are not, though.

I see in your profile that you have an afc on your wish list...do you have it yet? If yes, and it's installed, then please post your corrections@rpm from 3K and up. This will answer the timing map question. And if it is installed, then I'd say add a little at 7K to get rid of the issue up there, unless you are already at 0% correction at the upper end of the afc and bumping into fuelcut.

95CarbonEclipse · 12-15-2007, 04:33 PM

The AFC is still on the "wishlist"

Would you mind explaining what exactly you're looking at so that, in the future, I can diagnose my own logs (other then what you've already posted)? I think I may need to re-adjust my byte rate because I'm only getting about 5s/s.

Romeen... I never answered you question regarding my Palm. I'm using PocketLogger on a Palm m515 and using PLviewer v2.05e (Oct. '07)

matthewdesigns · 12-15-2007, 07:22 PM

Sure. And this got long...sorry.

Some people tune using all manner of variables: wideband o2, egt, timing, knock, etc. I have no means of reading knock (stock 2g ECU's don't show this), I don't trust my stock o2 sensor to give an accurate reading, I don't have an egt probe/gauge....so I use the timing values. They are a fairly reliable place to look to with respect to what's going on with your motor as you increase power.

What you want to see is your timing curve rising in a steady manner. As your turbo comes on, building boost, your timing will drop in an attempt to hold off knock (looks like you hit full boost at about 3500rpm w/ 4*timing). The ECU will slowly add timing back in as your boost rises. This rising value is what you want to watch. If the timing curve is smooth, no dips or peaks, then you are generally in a safe place. The timing can drop and jump back up any number of times during a WOT run, indicating a number of places that a correction needs to be made. The only corrections you can make at this point are less boost and higher octane (see below).

Timing can get pulled back for a number of reasons, but the most common is knock. I'll assume you know what knock is, why it's bad, etc. You can knock from being too lean and too rich, but it's generally from a lean condition. Using a piggyback (afc) or a true tuning tool (dsmlink) will allow you to change airflow and fuel input values, and modify the amount of fuel injected. Which will allow you to help to control knock (one of many ways). Since you have no way of doing this, then your two tools are: boost and octane.

I "tuned" with boost for a while, and basically what you are doing is looking for the highest boost you can run before you begin to knock, and subsequently see a timing drop. The other way you can "tune" is to increase the octane rating of the fuel you are using. This allows you to run a higher amount of boost without knocking. But what that really leads you to is another opportunity to increase boost pressure

So, if you are inclined, turn up your boost another psi and see if you get a dip in timing somewhere in the curve. And then perhaps again, until you see a dip. Then back it off to the a point just below where you started to knock. DO THIS AT YOUR OWN RISK! As always, raising boost pressure can lead to any number of things going wrong, from blowing off a coupler, to melting your motor. But, I have never had a problem by using merely the timing numbers as a tuning tool.

95CarbonEclipse · 12-15-2007, 08:01 PM

WOW... thanks for taking the time to type that out. One more question though... what is the importance of the air flow numbers?? Also, I'm assuming it's not an issue or else you would have mentioned it, but shouldn't my TPS be reading closer to 100 at WOT??

matthewdesigns · 12-15-2007, 08:45 PM

The airflow and rpm values, when inserted in a handy formula, give you a way to look at calculated airflow as the ECU sees it, expressed as grams/revolution. There are a couple of timing maps (I'll have to find the charts to give you an accurate answer) built into the ECU that relate airflow to timing. When you are flowing more than 2.1 gm/rev, then the ECU puts you onto the highest map, capping the timing at 16* advance on 2g's. The reason I mentioned earlier that there was a "potential question" regarding upper timing was that, at least on my car, as I get into higher rpm's, my turbo can't consistently keep me on the upper map. I go on and off of it, leading my timing to alternately be capped at 16*, rise higher as I fall off the upper map, then drop back down to 16* as I revert back. It can be confusing to try to figure out why you are seeing timing "pulled" at upper rpm's, thinking it's knock, etc., only to figure out that it's the whole map-hopping issue.

As for the TPS signal, I'd say if it's consistently 95% or better, I wouldn't worry about it. You might need a slight adjustment to the throttle cable to get it back to 100%, or it could be a fault with the TPS itself, not registering 100% when you are actually there.

I'll reply tomorrow with the gm/rev equation, and any info I can find on the timing maps.

123bobby123 · 12-16-2007, 10:17 AM

Hi,

Some awesome info in this thread. This document that I attached is more for DSMLink but it is real good at explaining the fuel maps and timing maps. It includes the formula to find gram/rev as well.

Also, Im not taking creadit for this document, just passing it on. Found it on these boards but forget exactly where.

Bill

matthewdesigns · 12-16-2007, 10:47 AM

^^^ That's what I was going to dig up this morning. Thanks for posting it Bill. Also important is the short list of variables listed at the end of the document that can change timing...more input to consider...yeah!!!

Here's a link to a thread that I've found to be really helpful regarding airflow (thanks to spyder007turbo and his great explanation of things). There is also a much more user-friendly formula for calculating gm/rev in that thread than in the DSMLink paper above. Start at post #51.
Tuning...... A stupid question

95CarbonEclipse · 12-16-2007, 01:56 PM

WOW this is a great thread full of info. Thank you to everyone.

That DSMlink tuning .pdf is exactly the type of literature that I'm looking for in order to educate myself on tweaking my car's performance and how the ECU itself works. With a little more reading I should have a pretty good understanding of how timing maps and fuel maps effect the overall performance.

God, I wish I had DSMlink.