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Hey guys. Got a question about tuning my car. I have a WB O2 sensor that I am datalogging into HPtuners and when my car comes into boost the AFR is pretty rich like 10.3:1. I want to bring this up a tad so I need to tune my VE table some. Is there a histogram I can use or make that will logging this rich AFR in the histogram and show me exactly which cells to alter in my VE table? Thanks in advance.
I have to agree, I think the histogram/PIDS are the most confusing part of HPT. I wish I could find a good "how to" on making/using histograms/PIDS/configs.
Curious, are you using BE on your setup? Is this something you can just change your BE/PE table to dial in, or is your VE off?
Have you seen Greg Banish's DVDs by chance? He goes through that type of thing in detail.Quote:
Originally Posted by tording99z28
The short answer is yes. You can create a variable that is the error between commanded AFR (or Lambda) and actual and use that on a histogram with the same x/y axis as the VE table to make it easy
Yes the PE table could be used to dial this in probably but I am pretty sure the proper way is to dial in my VE table. I am not really sure why I think this just seems to me that changing the PE table would just be a work around when the real issue is the VE table needs to be corrected.Quote:
Originally Posted by rpturbo
No I have not seen Greg Banish's DVD on this but I would love too. I have a histogram that is already built called AFR Error % so I am guessing this is what you are talking about but I was confused about the error %. What is the error % measured against. Based on your comment I guess commanded AFR. I know what my commanded AFR is during cruise but not sure how to tell what it is during WOT. Is there a table somewhere to change this?Quote:
Originally Posted by schpenxel
There's a symbol to the right of the numbers for the different histograms where you can go in and see what all of the histograms are being built from.. so I'd start with seeing what that histogram you are looking at isQuote:
Originally Posted by tording99z28
Remember you need to add whatever you want to work with to the "table display" view first, I think anyways
Are you using the default config that comes with HP tuners or you have downloaded someone else's, or changed something on your own? I ask because I highly doubt anything would be setup to compare wideband readings vs. commanded AFR/Lambda values correctly without you setting it up specifically to your setup. The default config def. doesn't come setup that way
Yes I had a local guy tune my car last year and it is his config file. I am tired of paying someone each time I want to tune though so I am doing it myself. I am a pretty smart guy when it comes to cars and computers so I know I can do it, just nerve racking when dealing with so much power but have to start somewhere. It is a SD tune so no MAF to worry about so fairly simple and I understand the concept just wanted to see if there was an easier way to overlay the rich WOT condition on top of my VE table to make edits.
so make a pid to show wb vs commanded and lay it over the ve table histogram
If that histogram is populating when you're logging, then you're already logging the commanded AFR also. On the table (not the histogram), you should see something like "Air Fuel Ratio Commanded Hi Res". This takes into account the PE and/or BE values commanded. After that, if you've got HPTuners Pro and you're logging your wideband as "AFR" then the default config will work. Histogram 6 should show you your actual recorded AFR, and histogram 7 should show you the % error between what the wideband is measuring and what the vehicle is commanding.Quote:
Originally Posted by tording99z28
Yes, it should be comparing the commanded vs. actual read by the widebandQuote:
Originally Posted by tording99z28
Read up on power enrichment table. Basically the computer takes the "normal" stoic AFR and divides by the power enrich ratio when you are in power enrichment mode (PE). WOT is def. PE mode unless someone has done something dumb.
So if you're set to run 14.7 stoich normally and at 5000 RPM's you have a PE ratio of 1.3, the car should be running (well, COMMANDING) 11.3 AFR@5000 or if you're using Lambda, .77 Lambda. If the VE or MAF tables are wrong then the actual could be different, thus the purpose of a wideband
The error # in the histogram should take all of this into account and give you a final error between the commanded AFR and actual, regardless of whether in PE mode or not
Also, someone linked to this in another thread which is probably a decent place to start:
http://www.redlineforums.com/forums/...ve-tuning.html
Ok I think I got it. So the only change to the Commanded AFR is the addition of the PE table when in PE mode. So my commanded AFR is 14.6556XX and my PE is 1.3 then just take the Commanded AFR and divide it by the PE ratio and that is the commanded AFR for WOT? That makes total sense. So what is the proper way to tune for WOT? Change the PE table to get A/F's aligned where you want them or change the VE table to do the same thing? They should both have the same affect but I am sure one is better than another? I have posted my logs and tune and config file. Also my car is seutp in Speed density so there is no MAF to mess with any of the fueling.
You want the VE table to be correct first.. for the lower RPM tuning you can set PE and any other enrichment values to to 1 first, then adjust the VE table so that the commanded/actual end up being the same. That gets a little trickier with WOT since you don't want to run 14.65 at WOTQuote:
Originally Posted by tording99z28
After the VE is correct, when you change the PE back to something greater than 1, the computer shouldn't have any trouble calculating everything correctly and delivering exactly what you've asked for
Your MAF table needs to be right too, if you are using a MAF sensor
Ok I understand what you said above and I have done that. I have cruised around and adjusted my VE table so that at cruise and lower rpm's my STFT's and AFR error is very low +- 5. I also changed my PE table so that my commaneded AFR at WOT is going to be 11.2:1. I just went and did some datalogging at WOT and for some reason for the first half of my WOT my commanded AFR is 11.7 and then it drops to 11.2 right where I want it to be. What is causing the commanded AFR to be 11.7 at first? Is there a table somewhere I am missing causing this? I have attached a log and you can see there are 2 spots where I went WOT and in both times the commanded was 11.7 at first then dropped to 11.2.
Quote:
Originally Posted by tording99z28
Post the tune as well--you only posted the log. Sorry for the slow response
Also, what are the specific RPM's where that happens?
There needs to be certain criteria met to enter PE, BE such as MAP KPA etc. Depending on application N/A, F/I you adjust the KPA to accommodate. Example of my 6.0 when N/A the KPA was 55KPA and the throttle position was 85%. My F/I application the KPA is 105 and throttle is 40%. That's what logging does for you. It will help in the process of fine tuning where PE and BE would come in. There is also RAMP IN RATE which will tell the computer has fast to bring the ratio's to what your commanding.
Indeed, I was going to say basically the same. Which is why I was asking for a copy of the tune and specific rpm'sQuote:
Originally Posted by Cyrperformance
Also whatever you want to show in a histogram HAS TO BE IN THE TABLE. You were correct when you stated just the I think anyways may get lost.