Question about being lean

[kliped]

Hey guys I have a question about being lean on e85. To give a little background I have a 2011 ctsv with a couple mods and a flex fuel sensor. i am running the aem 30-0334 wide band to monitor my air fuels. I was remote tuned by a very very reputable tuner.

While drag racing, in 2nd and 3rd gear, my air fuel ratios are in the mid 12s. In 4th gear they are in the mid 11s. my question is, is this something i should at all be concerned about? I have brought they up to my tuner because the car was actually a little leaner, hitting low 13s air fuel at some points, so he revised the tune a little. I have never had a car that ran on ethanol so i really do not know what to expect from it, but in the past I have always tuned my boosted cars to run in the mid 11s a/f. I have attached two logs, run1 is before the revision and run8 is after.

am i being concerned over nothing?

[Area47]

tune file?

[kliped]

tune file?

i would like to post it but i dont think my tuner would like that too much.
my main concern is if you guys think that thats too lean for a boosted car making maybe 650+ at the wheels on e85

[07GTS]

hard to tell without the tune file, your EQ ratio commanded is 0.780 and your WB says about 0.820 so your tune needs adjusting so it is closer to commanded (should be much richer then u are according to commanded), dont worry bout AFR with ethanol just look at the lambda much easier when its changing all the time, EQratio v WB Lambda, i run about 0.82 @ 14 psi e85 works fine but each engine may like to be slightly richer or leaner

[Rodsctsv]

I run around 80 on lambda , 12 ctsv coupe with FBO and E80 , I run the AEM 30-0333 and suggest switching to lambda,, 82 is a little lean on daily hits IMO mayb on trac days a few times . I'm at 75 with NOS

[5FDP]

Meh, post the tune anyway.

If the tuner was that proud of his work he wouldn't even let you post on a forum lol. Think of it as constructive criticism.

[Rodsctsv]

I know most remote CTSV tuners , I'm on my 3rd , I do most of the tuning now but still need help with the tranny

[Area47]

it's one of three people off the top of my head. I have seen them all. There is not a great secret in the tune. If there was, you wouldn't be asking for help.

[apedraza]

newbie here, I have a 2013 Silverado 5.3 dod/afm delete L/T off road y-pipe with prc ls6 heads and 220r cam along with 4.11 been running e85 as well I had the truck tuned but got tired of going back and fourth with the tuner. ive been having issues with idle hunting at times at the stop light and stalling when turning to do a 3 point parking. so I bought a ecm and loaded stock tune in it and disabled all of the dod b/s so far it starts fine and idles ok, I did notice during the licensing fscm from a Cts-V. basically looking for some pointers on just about everything and what I should target air/fuel during cruise and WOT thanks

[kliped]

alright, ill upload the tune. i went ahead and just pulled it from the ecm just so that there are no obvious identifiers or at least i dont think there are. Overall I am really really happy with the tune and how the car runs and performs, i am just a little concerned about how lean it is.
one other question i have when you guys look at it is that i noticed my mph is off some from what i actually trap (also based on transmission gear, rear end gear, tire size and rpm) and i compared the tune file to my stock one and see that he made some changes to the speedo, is there any reason to make such changes or can i put them back to factory spec.

thanks!

[GHuggins]

Ummmm - what's the build? LOTs of weird and questionable changes in this tune...

[kliped]

Ummmm - what's the build? LOTs of weird and questionable changes in this tune...

2011 ctsv auto

2.45 upper
flex fuel sensor
id1050x injectors
kooks 2in headers/ xpipes no cats
brian tooley stg 3 cam
prc dual valve springs
btr 7.4 push rods
dw300c pumps
under hood ice box

[07GTS]

for a start your flex adjustment is never going to be right if the stoich table has been changed should go back to stock stoich table then retune fueling that should help with commanded equaling WB once corrected

[Area47]

Ummmm - what's the build? LOTs of weird and questionable changes in this tune...

i think the 7100 rpm limiter is a giant red flag. but that's me.

[kliped]

i think the 7100 rpm limiter is a giant red flag. but that's me.

i am a bit naive, why is this a red flag? the car does shift long before it gets to the limiter

[GHuggins]

Besides the timing table, screwed up stoic table, injector tip temp zeroed out to throw fueling all out of whack, lots of things either maxed out or disabled regarding throttle controls - the rev limiter was the main reason why I asked what had been done... If the oil pump wasn't upgraded the stock oil pump starts having problems with cavitation above 62 to 6500ish... Ever heard of stock ctsv's spinning bearings? Well anyway, I could go through the whole tune, but you just need to start over... Also don't believe your tuner has a full grasp of the cot/pe adder - he put the same value in both tables probably thinking that the tables add together and then get added in during PE for alcohol, but they don't - if your running alcohol, the alcohol table is the only one adding in... Anyway...

[GHuggins]

In fact, I would like to know what the air/fuel ratio is with a good wideband that your car idles and drives along at? It's being leaned out via injector tip temp offset and stoic tables... All of that combined with headers and relocated O2's should make it even leaner - if your lucky the added air velocity in the exhaust from the blower changes has thrown things rich, but I doubt it???

[kliped]

Besides the timing table, screwed up stoic table, injector tip temp zeroed out to throw fueling all out of whack, lots of things either maxed out or disabled regarding throttle controls - the rev limiter was the main reason why I asked what had been done... If the oil pump wasn't upgraded the stock oil pump starts having problems with cavitation above 62 to 6500ish... Ever heard of stock ctsv's spinning bearings? Well anyway, I could go through the whole tune, but you just need to start over... Also don't believe your tuner has a full grasp of the cot/pe adder - he put the same value in both tables probably thinking that the tables add together and then get added in during PE for alcohol, but they don't - if your running alcohol, the alcohol table is the only one adding in... Anyway...

thats a little disheartening to hear, my tuner is supposed to be one of the best remote tuners out there and comes highly regarded on every LS forum out there. Like i said, the car runs great, smooth, idles perfect and starts on E with out hesitation. Traps 135mph in the 1/4 mile. Im just baffled how he could be so far off.
I understand tuning is a bit of an art and there are different ways to achieve the same result, could this possibly be the case?

[kliped]

In fact, I would like to know what the air/fuel ratio is with a good wideband that your car idles and drives along at? It's being leaned out via injector tip temp offset and stoic tables... All of that combined with headers and relocated O2's should make it even leaner - if your lucky the added air velocity in the exhaust from the blower changes has thrown things rich, but I doubt it???

while its not a top of the line wideband, while cruising my aem 30-0334 reads consistently mid to upper 14s

[GHuggins]

I'm seeing 14.2 to 15.9 swings in places in that log - you can put stoic table back stock and possibly help with a lot of your issues, then fix O2 tables for the swings, then dial in timing better, then put safeties back in as a quick fix...