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tgeers
June 14th, 2006, 10:39 AM
I know what you're thinking. No way! However, I've been using the EFIlive SD tuning program to tune my 02-C5. All has gone well except now I'm trying to tune my WOT using the VE and PE tables. I'm trying to set the AFR at 13.0 but the best I've done is 12.5. I've tried all kind of combinations that I'm too embarrassed to mention, but nothing seems to help.

Are there any suggestions? I hope you can help. I'm going racing this weekend.

Thanks for your help.
Tony

GMPX
June 14th, 2006, 10:49 AM
Well, leave the P.E set to the desired AFR you want (13.0:1 in your case) and just keep playing around with the VE table, if you are running S.D it 'has' to modify the final actual AFR if you change the VE table.

Cheers,
Ross

SSpdDmon
June 14th, 2006, 12:24 PM
What does your commanded AFR read when you go WOT? Did you turn COT (cat overtemp protection) off? That can cause your car to command 11.7 or richer AFR's when WOT for more than 5 seconds or so. Check your commanded...

tgeers
June 14th, 2006, 12:35 PM
Thanks Ross,
You're not the master of the universe by accident!
So if I adjust my PE table to reflect the 1.0 Lambda I want in the lower rpms and then set the PE at .891 in the upper rpms where I would be during WOT, I should be OK then. Right?

What is the interaction between the PE modifier (B3618) and the commanded fuel in Open Loop (B3605) ? If I'm always in Open Loop which one has the greatest influence over my AFR?

Thanks again for your help.
Tony

Tordne
June 14th, 2006, 12:54 PM
PE mode only becomes active when the enablers are hit. For instance the MAP & RPM is over a certain limit, and the TP% is above the value in the Normal or Hot Mode enablers.

Otherwise if you are running in Open Loop the commanded AFR will come from the B3605 table (or B3647 in V3 Custom OS).

I believe that the richest value from the B3605 and PE mode will be used when in PE. I have never validated this as I run the V3 Custom OS and rely solely on B3647 for fuelling.

Cheers,

tgeers
June 14th, 2006, 01:01 PM
Sspd Dmn
According to what I have learned from Ross my Commanded Fuel was too low.
I've already changed it, but I believe it was .789 when in WOT. Look at my reply to Ross and see if you agree with the changes I've made. I have over 100 logged files with corresponding changes. From idle (1000 rpm) to 4000 rpm my corvette runs right at 14.6 AFR. That's the area I've concentrated on. Now I'm starting to work on the higher RPMs. It's hard to log data at 5,000-6,700 rpm on the local streets and expressway. The cops don't like you doing 120-130 mph on the interstate. They have no sense of humor.

Thanks
Tony

SSpdDmon
June 14th, 2006, 01:18 PM
Assuming Lambda*Stoich=AFR, then you're kinda right. PE shouldn't have a lambda of 1.0 anywhere. I set mine so my AFR is 12.2 up until peak torque, then lean it out to 12.8 at peak hp, then richen up a little after peak hp. With those numbers, you shouldn't have a Lambda lower than .834 (12.2AFR) or a Lambda higher than .875 (12.8AFR) in the PE table.

joecar
June 14th, 2006, 03:52 PM
Will this help... showpost.php?p=22806&postcount=12 (http://forum.efilive.com/showpost.php?p=22806&postcount=12)