racecar

When I turned the MIL off before, the car would not start. That was without any change to the MAF value. I will try it with a low number in the MAF fail. If it starts, all is good. Back in an hour.....

2000c-5

I'm not going to get in a pissing contest with you. My tutorial is the same thing that is in the VCM Suite help files.When you convince Ken, Keith and Chris at HP Tuners that the way they teach people how to tune with the software that they created, then I will stop helping people learn how to do it. Meanwhile, you might want to get some help for that OCD.

2000c-5

You should just have to set DTC to mil on first error and turn off SES. You can set the MAF Fail freq to 0 or, with a '99, you can unplug the MAF. The '97-'00 have separate MAF and IAT.

racecar

It was set to MIL on second error. If I unchecked the box, it would not start. I never tried MIL on first and unchecked.
Tonight I just set the freq to 0 and it starts with no Check engine light, so I should be ready to go tomorrow. Thanks to everyone for all the good input. I just installed this LS2TB and FAST90 this week without MAF and with the SD tune, so it has really been a scramble to make it work. I'm glad that everyone is willing to share there experience. Today was way better at the track, AFR was close (12.0-12.4) , I think I can nail it right on 12.7 tomorrow I will let you know how I do in the race. Next week I will start logging to get the VE table straightened out in the mid range.

2000c-5

Cool, keep us informed.

racecar

I started the car and turned on the data collection on Pre-Grid about 2 minutes before the race, then they went on a hold. I turned the car off and restarted a few minutes later. That screwed the data so I can't tell if the AFR is better. It ran good, pulls strong to 6500. I got a slow start and got passed by 2 Porsches, ended up 5th. A 2006 Z06 won the race.
What's the goal here for AFR? I know that 12.7 is the best for WOT and racing conditions. 14.7 is for cruising. 14.7 for idle?? What about cold start and idle, what should the target AFR be? Right now I am way rich at idle (12.0) and about 10.5 at cold start up.
It smells rich.

2000c-5

Fifth isn't bad at all with that level of competition.

AFR for a '99 vette is 14.63 (See Engine/Fuel Control/General). This is the AFR that you want for everything except WOT.

Idle should be 14.63 also. You tune it when you are doing the VE. Be sure the car is completely warmed up before any tuning. There are tables that add fuel until you reach operating temp that will throw off readings. If you do the VE correctly it includes idle also.

When you go back to closed loop your AFRs will be 14.63, because that's what the O2s do. You tune the VE so that the O2s don't have to work to find stoich, this gives you your throttle response. Also, when you hit PE while driving, if you enter PE from a cell with a positive Fuel Trim, say +5, the PCM will add 5% fuel the whole time you have your foot down. So if the VE isn't in line, your AFR at WOT could be different each time you floor it. At the end of tuning, your fuel trims should be between 0 and -4. That way you will never enter PE from a positive Fuel Trim. The PCM won't subtract fuel so, negative trims have no effect.

Be sure you do your math for PE using 14.63. And an FYI, some people will richen the fuel slightly between 4000 and 5200 rpm in the PE. This is where a corvette makes peak torque. After 5200, the AFR is the same as it was before 4000 rpm. The best thing to do is put it on a dyno.

racecar

This was my first race this year, so I am still getting up to speed. Everyone else has run two before this one, they were all over me. It takes me a couple of laps to get up to speed. Thanks for the tuning tips. I will shoot for 14.63 overall and 12.7 at WOT.
What do you expect to see at cold start? 13.7 ?
I can understand a little richer at 4000-5200 peak torque, may have more tendancy to spark knock.
I am flat at 25 degrees with 11.5:1 static compression. I had knock problems last year, and found that when I shift and lift off the gas, it was advancing due to the idle spark table, then it would knock when I hit the gas again. Flattened that table to 25 and solved the problem.

Ragtop 99

iTrader: (7)

The Mround function in Excel has been helpful. It allows you to round to any value you want. For example, you can round rpm to the nearest 200 rpm and and get data back at 1200, 1400, 1600, 1800, 2000, 2200 and use only the points for for 1200, 1600, 2000. I round the MAP data to the nearest 5, but that can be changed to 2 to help filter it for 5 kpa.

Mround is in the analysis toolpack.

SSpdDmon

iTrader: (10)

I would think that requires access to the raw data though, right? I don't have that.

5.7 ute

I cant see rounding the data in excel to be any benefit. Trying to remove the data which is not in the cells centrepoint & is skewed by interpolation is the goal. Apart from some heavy filtering or tedious cut & pasting from an extremely detailed map I cant see any easier way to accomplish this.

RedHardSupra

iTrader: (1)

don't remove data from non central areas, you're just eliminating potentially beneficial data. what you want to do is to take averages of all the values in the area. it's really hard to do in excel, does anyone have a good method for it?

5.7 ute

I am trying to work something out now where a more detailed map can be used to work out the average cell value. Basically I figure that since the ve look up value is unmolested by modifiers the maths behind the interpolation should stand out in a good log. This should allow the corrections to be applied to the actual logged data & then worked out back to an absolute cell value. Mind you if I am wrong in my thinking it wouldnt be the first time.

Ragtop 99

iTrader: (7)

A pivot table using MRound data will do that.

1) Create an extra fields for rounded for rpm, rounded KPA, and average STRIMs (or what ever variable you are using; I don't have a wide band). Use 400 as the round factor for rpm and 5 (or 10 depending upon the year) for your KPA table. Now all of your data will be assigned to a cell that corresponds to the VE table and you'll have 3 columns of new data: rounded rpm, rounded KPA, and average STRIMS.

2) Create a pivot table based upon your new data. Rounded RPM for columns, Rounded KPA for rows, and STRIMS as your data items. If it gives you the sum of the STRIMS, double click where it says "sum of STRIMs" and select average.

SSpdDmon: you can export the data from HPTuners to Excel.

RedHardSupra

iTrader: (1)

yes i know pivot tables are the way to do this in excel, but they're very interactive, you gotta go through the full process manually, no way to paste numbers, hit 'go' and have it pop out at you. or can you do it this way i just dont know it? i will buy you a very large beer if you got a method for it.

SSpdDmon

iTrader: (10)

<< EFILive user

Ragtop 99

iTrader: (7)

Red: I'm not sure I understand the question. Is it the pivot table that is the problem or is loading the new VE data back into HPT with a copy and paste the issue? The pivot table is literally about 5 clicks and 3 drags of the mouse.

I haven't touched my tune in a year, so I'm rusty with the software, but IIRC you can copy and paste your VE table between Excel and HPT.

You're right that it is not as automatic as it should be, but the process should take about 10 - 15 minutes from the time you export the data into excel from HPT to when you have a new VE table to paste into HPT.

RedHardSupra

iTrader: (1)

i guess my annoyance with it is if it's always the same 5 clicks and 3 drags, why can't it just be there permanently and we should be able to add different data. 15 mins of dicking with software is entirely too much when tuning, especially when you're on a laptop in a middle of nowhere. add sunlight and trying to drag things around with the laptop nipple/touchpad, and it's an error prone nightmare.
so no automated way? oh well...

Ragtop 99

iTrader: (7)

once the pivot table is set up, you can put new data in and update with a click of a button.

I see your frustration, but I remember having to write programs to do most functions that Excel now does, so its all relative.

RedHardSupra

iTrader: (1)

really? i thought you had to pick the data range every time. did you set it up with dynamically named ranges or something? i've done it before, but never for pivot tables... anyway, i've been building a whole slew of utilities in MatLab so I got way more power already than HPT/EFILive scanners and Excel have given me.