Ok yesterday I tested my car in 4th gear after work and attached is the log in which the temp outside was 60 degrees about 63% humidity, today I ran a 4th gear pull same humidity, 80 degrees outside same section of highway after work, only diff in maps is that I pulled 1 degree of timing around peak torque where I was experiencing 5 -6 sums of knock, and pull a lil timing around the 5500 to 6300rpm range and the pull today felt much better today, full throttle about same rpm. The results are shown in Datalog Lab Dyno. Todays pulls felt better than yesterdays and that is with more conservative timing and also no changes in airfuel. Attached are logs and a pic of the dynoplot(using for measurement purposes). Stock boost control error correction on, changed load offset from 60 yesterday to 80 today since we are mapping the EVO8 load like an EVO9 ecu using stock error protection and desired load at 159.4 all the way. Interesting results with hotter weather Opinions welcomed

4th gear



3rd gear actually hit 7031rpm on the log, but didnt show that on the graph for some reason, but today I hit 7200 in 3rd gear.

 

Also to add 93 octane both runs, same gas station also for DataLogLab dyno are we suppose to use the temperature settings and barometer settings from what the car has logged or just the settings for that particular day on a weather site or weather channel

 

not true

 

I know normally it is not true lol, but today it seems that way. Maybe the 1 degree pull in timing made the difference

 

Density altitude is a weird thing. Use this calculator to see the effects on power:

http://www.csgnetwork.com/relhumhpcalc.html
http://wahiduddin.net/calc/calc_cf.htm

Some good reading:

http://www.land-and-sea.com/dyno-tec...horsepower.htm
http://www.greenheck.com/technical/t...guide/temp_alt

 

nice links

 

Cliff notes- High Humidity doesnt like Low temps.

High humidity means there is less available oxygen per cubic foot of air. Lower temps mean its denser and less oxygenated for the same conditions otherwise, i.e. a cold dry day can make good power where a cold wet day will be crap.

 

little off topic but how did you get the overlay of different logs in DLL? I can only do one log at a time.

 

I'm curious how you go about doing that.

When you say you pull timing what is involved?

Meaning: do you look at what load cells you're hitting and just pull timing in those?

If you fall in between cells how do you know which one to pull timing in?

 

You log 1 run draw it in datalog lab. And then dynoplot it. Once you got the dynoplot up with correct factors include, (weather, humidity, weight ect) go ahead and save it as a .pow file somewhere and remember where you saved it. Afterwards make your changes where you think you need to make them, log the run and draw it again, and then dynoplot it again, this time when you dynoplot it let the graph sit there and then click file open and open your first saved graph and and click drawgraph again. You will notice after you open your file again the benchmark portion will change to the file you opened. Only thing I am not sure of is do I use the temp settings for what the car is seeing(what I currently use) or do I use the temp settings from whatever the weather is that day outside.

 

Well in this case I was seeing 6 and 5 sums of knock from 3700 to about 5500 . And all I do is look at the load point on the hi map where the knock occurred and at what rpm. I pull(decrease) timing there then I smooth out the transition in the cells around it. As far as knowing what cell you in, you really don't you just have a general idea based on what you see, but I normally change the cell after. For example if I am at 3800rpm 257 load calculated, I change 4000 @ 260 and then smooth out cells around it. Plus that is a reason why I tune the car reduce timing per load so that way say next run my car only hits 238 load at 3800 well it will see generally more timing available at 240, because there is less load there and MAFs although accurate in measurement can be unpredictable as far as what I have seen. If you smooth your transitions from 1 cell to another you should be able to get a smooth timing map, and you can pretty much tell your transitions are good based on the color changes in the map.

 

I'm trying to figure out exactly what smooth out the cells around it means...

Say you have a grid like this:

9 8 7
10 8 5
10 10 7

and you want to change the 8 in the center. What do the cells around it become?

 

depends on what rpm your at normally between 3500 to 4500 I keep timing close to the same and then come back up no matter what load point I am at.

 

Are you sure that wasn't 5th gear pull?

Your seriously hurting in power somewhere -

5.2 seconds to accelerate from 3500 RPM to 5500 RPM in 4th.

What does your timing look like?

Oh yeah, some wise man once told me to start the pulls low like 2000 RPM, not 3400 RPM

 

Sorry cant slow down on freeway to 2000 in 4th gear that would be like 45 mph.