Hey guys,
I'm just curious what you other forced induction people get for AFRs come winter time assuming you are in a climate where there is a winter.. IE snow.. ice.. etc..
I was curious because mine is starting to lean out now that its colder and just wanted to see how much more lean others get from the cold. I have my car tuned for 12.1 and it usually stays around that but now its close to 12.8-13.0. I might add more fuel but most likely ill leave it since i dont get on it much in the winter anyway.. This is with the M62 btw..
So on average what are you experiencing for AFRs in colder weather?
12.33 @ 111.67 mph [Oct 2009]
Dyno'd on 08/02/09 - Mustang Dyno:
327.6 WHP 333.6 WTQ [10.1 AFR]
This will be my first winter with the charger so I'm looking forward to seeing how much it changes. Should change because cooler air allows more boost, so more fuel is needed.
N/A I would see a difference from like 12.7 warm to 13.2 winter.
FU Tuning
It's a natural occurence, yes. Cold air = more density = more oxygen = leaner AFR
An easy way to offset it is fuel pressure. If you have an adjustable regulator, just take her up 5-10 PSI in winter, take it back out in the summer.
Sure, you could work with injector constants and/or any number of other tables until you just want to put your fist through your laptop. With today's tuning tools, its not hard to overlook the ease and simplicity of fuel pressure adjustments.
Bill Hahn Jr.
Hahn RaceCraft
World's Quickest and Fastest Street J-Bodies
Turbocharging GM FWD's since 1988
www.turbosystem.com
if we had access to IAT VE modifiers you wouldn't have to change anything else...
That said, do you see any KR with the cooler, leaner condition? I don't need to tell you this, but the main source of KR on the M62 is the heat. Lower the IAT and you don't need pig rich AFRs to avoid KR.
This whole incomplete HPT thing still pisses me off a little bit. You should have access to the tables you need to adjust the multiplier responsible for IAT vs VE or AFR
IAT alone would not be enough. To really nail it on the boosted cars over the winter-to-summer range, one needs MAF too...which of course, these don't have.
Bill Hahn Jr.
Hahn RaceCraft
World's Quickest and Fastest Street J-Bodies
Turbocharging GM FWD's since 1988
www.turbosystem.com
Sorry changing the injector constants alone would not make a difference.
Now for me after this winter it will not be a big deal because I will have the socalled higher boost level tuned. Since my car reads boost (Gm reflash) once I tune the higher KPA the ECU will add the fuel I need when I see the change.
FU Tuning
Why not run the other ECM you have that is made for the charger?
Chirs
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
If you are running a map based tune such as the GM reflash it should not change much. I am pretty sure the OP is running a fake 2bar correct me if I am wrong.
FORGET GIRLS GONE WILD WE HAVE GOVERNMENT SPENDING GONE WILD!
Correct.
But I flashed another ECM for him with the GM flash...
Chris
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
Its not a huge deal about running leaner, i was curious what others experience in terms of AFR from warm to cold, since most of us know that colder air is more dense
, i just wanted some data
Im running the fake 2.5 bar. I dont know if i have any KR, id have to log. if i do its probably around 4* which it is usually near around 13.0 AFR when its warm..Not too worried about KR though, the built motor is one tough guy.. withstood a 100shot at 13.2AFR for 2 gears haha..
I could increase FPR by 5, that might be a good way to do it instead of tweaking the IPW Multiplier
thanks for the tip bill
I dont have the LSJ injectors anymore so the injector constant would be off and the car could run like garbage. I have mine tuned pretty well for low RPM cruising, so i get decent gas mileage driving under normal (non WOT) conditions. When i filled up this morning i had 283miles to 3/4 tank of gas so not too bad.
Chris, something else may be affecting the car as well, last time i tried to use spray it started spraying then my car died a second after it sprayed and when i was able to start the car again, i had a fairly large vacuum leak from around injector cup 4 which i *think* i fixed by reseating the injector cup with a new oring.. unfortunately the injector rail ear that is on the head to hold the rail down is broke off on that side... JB weld failed or I failed trying to use JB weld lol but it seems just about all the way seated; may not be 100% tight but its been ok until recently.. If i have a leak it would be causing me to run more rich under boost so that is why i concluded i dont really have a leak or if i do its not that severe.. if its not the cup, it may be the manifold gasket, but i dont have time with school.. or the desire to check since its really cold outside..
I just want a new car lol.. built one, now i just want to buy one.. that way i can do a few things to it to make it quicker rather than a lot of things..that way if something goes wrong i dont have many things to check.
12.33 @ 111.67 mph [Oct 2009]
Dyno'd on 08/02/09 - Mustang Dyno:
327.6 WHP 333.6 WTQ [10.1 AFR]
Be at my work around noon this sat... we'll take a lookie.
Besides Wade is coming up!
Chris
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
k ill see what i can do, ill send you a text on friday
12.33 @ 111.67 mph [Oct 2009]
Dyno'd on 08/02/09 - Mustang Dyno:
327.6 WHP 333.6 WTQ [10.1 AFR]
Quote:
Not too worried about KR though, the built motor is one tough guy.. withstood a 100shot at 13.2AFR for 2 gears haha..
That is just asking for trouble!
FU Tuning
John Higgins wrote:Quote:
Not too worried about KR though, the built motor is one tough guy.. withstood a 100shot at 13.2AFR for 2 gears haha..
That is just asking for trouble!
I cant say I wasn't nervous at the time lol but it held up..
12.33 @ 111.67 mph [Oct 2009]
Dyno'd on 08/02/09 - Mustang Dyno:
327.6 WHP 333.6 WTQ [10.1 AFR]
12.5:1 year round.
2002 Cavalier 2200 5spd
Solid Snake wrote:12.5:1 year round.
Hope you are not running stock internals and over a few pounds of boost.
All mine are at a steady 11.7-11.8
P&P Tuning
420.5whp / 359.8wtq
ImPhat0260/Cavattack2000 wrote:Solid Snake wrote:12.5:1 year round.
Hope you are not running stock internals and over a few pounds of boost.
All mine are at a steady 11.7-11.8
soon to add another to the list
mine is tuned to add more fuel the cooler it is outside and vice versa, but i'm MAF tuned by trifecta...dont think you have that option...
Keep in mind guys AFR is based on weight not by volume... So density does not matter. I dont know why the OP's numbers are changing but I hold the same AFR's no matter what. It was 11:0-11.3 solid in the heat of summer, and remains thus far this past week when it got down to low forties in carbondale. Bill I would like to know your thoughts on it, I'm on the GMSC tune with the 2200 so maybe my case is different. MAF just simplifies the PCM's job of calculating how much air is being taken in.
Buildin' n' Boostin for 08' - Alex Richards
I haven't driven the car in a few days due to frost and the cold weather but last time I had the car out I was still running in the 12.2-12.4 range and thats what I ran all summer...its been between 5-10 degrees celcius the last little while, but I have some days off coming up so I'll take the car for a good rip and see if has changed since.
Well I installed the wideband back on the car and wow did my AFR's get lean in this cooler weather we are havinh in Fl. Went from 11.4-11.7 to 12.4-12.7. Now my mixture I'm using on my meth injection has changed a little as well. IAT's went from maxing at 150-160 to maxing at 110-120, so weather has cooled off a lot.
FU Tuning
I have MAF and still notice a bit of a difference in AFR just because theres a SIGNIFICANT increase in boost 2-3psi or more. This amounts to 3-4 tenths in AFR which I can offset by increasing the methanol content of my water/meth mix, less water is needed in winter anyway
1989 Turbo Trans Am #82, 2007 Cobalt SS G85
do you mix your own water/meth? i just use the blue windshield washer fluid
12.33 @ 111.67 mph [Oct 2009]
Dyno'd on 08/02/09 - Mustang Dyno:
327.6 WHP 333.6 WTQ [10.1 AFR]
I mix my own...its probably cheaper than washer fluid and then you can mix it to whatever ratio you want and your not getting a bunch of other chemicals thrown into your engine...maybe I weird but I would rather know what was going in my engine.
I took the car out last night...it hasn't changed at all with the cooler air...it may actually even be a little richer. I was seeing anything from 11.8-12.3.
Again guys, so long as the car is running properly and the tune is done properly to emulate the OEM it should compensate for AFR changes based on air density. Remember as soon as the key is turned on and PCM powers up but BEFORE the engine begins cranking the PCM takes a BARO reading via the MAP sensor. This compensates for changes in density based on temperature and barometric pressure which becomes part of the speed density equation,
Remember kids,
[Displacement * #cyl / 2] * (MAP/BARO) * RPM * Vol Eff./ IAT * R - Purge Mass
Think of it this way, when your vehicle was stock, the changes in emission outputs is huge when your only talking 0.05 + or - Lambda do you really think the manufacturers would allow AF ratios to vary by as much as a full AF point just because it got a little colder out? The EPA wouldn't have it, thats for damn sure.
Buildin' n' Boostin for 08' - Alex Richards
