Cold weather-my a/f leans out too

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11-18-2008, 08:28 PM
farmtruc

Cold weather-my a/f leans out too

Hey Jay,

I've noticed during the cold days, the a/f ratio in my av is leaning out as well.
Of course it feels like it picked up 50hp.

Probably just making more power and needs more fuel.

just thought I'd share that,
allen
11-18-2008, 08:33 PM
Sleaper

Whew! Glad I'm not the only one! Mine feels the same way with gaining A LOT of power. I went to straight meth instead of 50/50 mix to try and keep it rich but there's still a small period of time where the AFR goes into the high 11's/low 12's but I'm seeing zero KR. Hopefully, I can make it back by to have it re-tuned with the cold weather......and get an inspection across the street!!! :D
11-18-2008, 08:58 PM
rutroe

Amen to that...I'm coming up on an inspection myself.
11-18-2008, 09:04 PM
SoHo48

the air is more dense... what allen said.. needs more fuel. afr is off because more oxygen can be saturated in cold air. need to add more fuel to get the ratio back right. My mustang was running so lean today I picked up a little detonation.. Stock tune at that.
11-19-2008, 01:52 PM
Wtfan18

what is a proper AFR range? i guess if im going to go FI i better start learning something about it...
11-19-2008, 01:57 PM
farmtruc

It might also be that the ltrims are slightly positive during the warmer days (not sure why on each application/vehicle) and what happens is the pcm will add additional fuel under boost if the ltrims are positive when going from closed to open loop, PE mode.

Not mine though, it just got leaner.

AF recommendations:

Normal driving and semi agressive:
14 to 16:1 a/f ratio

Aggressive to WOT NA:
12.5 to 13.0:1

Aggressive to WOT full Boost:
11.5

The more you boost the engine, the richer I take it, possibly going as rich as 11.0 at 15psi, just my suggestion.
11-19-2008, 02:02 PM
Wtfan18

well im only planning on running about 6lbs for now.

i guess my list of things to get are

bigger injectors #42
walbro Intake 255
AFR guage
Boost guage

what is is a necessity?
11-19-2008, 03:52 PM
farmtruc

Quote:

Originally Posted by Wtfan18

well im only planning on running about 6lbs for now.

i guess my list of things to get are

bigger injectors #42
walbro Intake 255
AFR guage
Boost guage

what is is a necessity?

In order to get 6psi you'll need some type of charger, belt or exhaust driven.
hahah jk.

those items listed above are the only things you'll need.
11-19-2008, 03:59 PM
ducky

I guess I need to start going WOT more to see if my A/F is being affected at all
11-19-2008, 04:05 PM
farmtruc

Quote:

Originally Posted by duckysbht

I guess I need to start going WOT more to see if my A/F is being affected at all

You just wanna come down for a retune, lol.
11-19-2008, 04:09 PM
CHEVROLADE

I Have No Idea What My A/f Ratio Is??i Guess Its Perfect Cause Its Still Runnin Strong.
11-19-2008, 04:19 PM
farmtruc

Quote:

Originally Posted by chevrolade

I Have No Idea What My A/f Ratio Is??i Guess Its Perfect Cause Its Still Runnin Strong.

You guys that don't check it scare me lol! Get it checked.:hyper2:
11-19-2008, 06:00 PM
Sleaper

Of course this afternoon with the warmer temps and running straight meth, my AFR runs back down into the mid 10's! :ugh2: I guess that's better than the alternative!!
11-19-2008, 06:42 PM
PurpleMinivan

Ahhhh.... maybe someday i can get SD tuned.?.?.
11-19-2008, 08:58 PM
GasGuzzler

Funny how people ignored me when I said cooler air is denser...LOL

I'm denser at night than at noon.

Hahahaha
11-19-2008, 09:27 PM
Sleaper

I didn't ingnore you. I agree that colder air is denser, but I didn't have this problem when I first switched over to the SD tune. It was only after I had it retuned for meth that the colder weather caused it to lean out. Not to mention, it doesn't lean out the entire time. It starts off ok then spikes to high 11's low 12's and then comes back down to mid 11's after a second or two. Just seems kinda weird. I have no doubt that you know your s**t! :beerchug:
11-19-2008, 09:29 PM
GasGuzzler

Hahaha

Doubt, please, doubt.

LOL
11-19-2008, 09:57 PM
ducky

Quote:

Originally Posted by farmtruc

You just wanna come down for a retune, lol.

I did a couple this evening even thoguh its not too cold out and it stayed right you put it the first time. 11.2ish. But ill be down in dec to get a retune and talk to you about that custom grind cam we need to get on order asap. My truck is already boring me.. :tacos:
11-20-2008, 10:07 AM
-HIC-

Quote:

Originally Posted by ramair2002

Of course this afternoon with the warmer temps and running straight meth, my AFR runs back down into the mid 10's! :ugh2: I guess that's better than the alternative!!

Actually this is not really true. Running to rich can cause cylinder wash then comes ring damage.
B
11-20-2008, 10:09 AM
ducky

Quote:

Originally Posted by -HIC-

Actually this is not really true. Running to rich can cause cylinder wash then comes ring damage.
B

lol the alternative being leaning out an going kaboom
11-20-2008, 10:15 AM
-HIC-

Quote:

Originally Posted by DBTBSS

Ahhhh.... maybe someday i can get SD tuned.?.?.

Why? If your MAF tune is working for you why would you change? If your MAF fails (very unlikely) you will be running SD anyway. If you think your VE table is off than just have it tuned on the dyno. I would make sure your MAF correction factors are nailed down, and you will be happier with a MAF tune. Unless of course you plan on doing some kind of FI, or you are maxing your MAF.
11-20-2008, 10:15 AM
farmtruc

I've been running the av at 10 - 10.5 forever, just a little safer.
Finally got a good retune on it last night, running strong with this weather.
11-20-2008, 10:32 AM
PurpleMinivan

Quote:

Originally Posted by -HIC-

Why? If your MAF tune is working for you why would you change? If your MAF fails (very unlikely) you will be running SD anyway. If you think your VE table is off than just have it tuned on the dyno. I would make sure your MAF correction factors are nailed down, and you will be happier with a MAF tune. Unless of course you plan on doing some kind of FI, or you are maxing your MAF.

I was just giving Allen crap. I'm basically SD tuned now to a certain point.... I have a mut tune:spit:. As soon as I can get all the nitrous stuff installed I will be getting dyno tuned. My TBSS hasn't moved in 3 weeks:(.
11-20-2008, 10:48 AM
farmtruc

Quote:

Originally Posted by -HIC-

Why? If your MAF tune is working for you why would you change? ...MAF.

SD tunes are a lot more stable, easier to tune and from what I've researched/done on the dyno, make a little more power.
Everytime a heavy head and cam package car or truck comes in, I don't mess around with maf tuning anymore, we go straight to sd tuning.
It clears idle up immediately and runs so much smoother.

Plus, you're not fighting two tables during tuning. For example, during start up, you use the ve table, then in closed loop it's mainly the maf stuff.
Do this, for those running maf and have hptuners, turn the maf off or put the pcm in open loop, notice how far each table is off?
Instead of fighting two tables, with SD you only use the ve table, it's easy and makes more power in the end.

Let's do this HIC, since you have our tuning, setup a retune appt with me and we'll tune your truck in sd mode and you can see how nice it performs.
Or, we can do this over email since you have the tools to do so.
Yes, it does take a little longer and we end up adjusting it once or twice after it "settles down", but in the end you'll like it.
Plus, since you have hptuners, you can just go back to maf if you don't like it; no need to remove the maf during testing.
Now for forced induction, if the vehicle supports it and it takes sd more correctly, that's the only way to go.

let me know, but that's my reason on why to switch,
allen
11-20-2008, 03:45 PM
-HIC-

Quote:

Originally Posted by farmtruc

SD tunes are a lot more stable, easier to tune and from what I've researched/done on the dyno, make a little more power.
Everytime a heavy head and cam package car or truck comes in, I don't mess around with maf tuning anymore, we go straight to sd tuning.
It clears idle up immediately and runs so much smoother.

Plus, you're not fighting two tables during tuning. For example, during start up, you use the ve table, then in closed loop it's mainly the maf stuff.
Do this, for those running maf and have hptuners, turn the maf off or put the pcm in open loop, notice how far each table is off?
Instead of fighting two tables, with SD you only use the ve table, it's easy and makes more power in the end.

Let's do this HIC, since you have our tuning, setup a retune appt with me and we'll tune your truck in sd mode and you can see how nice it performs.
Or, we can do this over email since you have the tools to do so.
Yes, it does take a little longer and we end up adjusting it once or twice after it "settles down", but in the end you'll like it.
Plus, since you have hptuners, you can just go back to maf if you don't like it; no need to remove the maf during testing.
Now for forced induction, if the vehicle supports it and it takes sd more correctly, that's the only way to go.

let me know, but that's my reason on why to switch,
allen

This could actually be a write up Allen. I am planning to change to a bigger cam in the next few weeks. After that ill have you hit me with an updated mail order maf tune. then I will make an appointment with you to do a dyno before, and then Dyno after with SD tuning. Sound Good? When it comes to tuning you know I trust your judgement, and I will never pass up a chance to learn something!
11-20-2008, 04:16 PM
-HIC-

Actually right before I change cams I will get it dyno'ed and we can use that as part of the original numbers. Then I will change cams, come up there with the mail order - dyno > then go SD and get the final numbers and drivability. Sound good?