Cold weather-my a/f leans out too

[farmtruc]

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

[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!!!

[rutroe]

Amen to that...I'm coming up on an inspection myself.

[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.

[Wtfan18]

what is a proper AFR range? i guess if im going to go FI i better start learning something about it...

[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.

[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?

[farmtruc]

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.

[ducky]

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

[farmtruc]

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.