Since the weather is starting to cool off some at night I have noticed a pretty big difference in my A/F ratios. You have to richen the car up a good bit at night to compensate for the Weather. Anybody have a chart or know about what temp changes will do to AF numbers. I know cooler=leaner but what does 20 Degrees F. Cooler mean.....4% richer on the S AFC???????? Something like that....
Cooler weather means that you're going to run higher boost, since cooler air compresses better. More boost = leaner AFR. Based on this, the amount of change will vary car to car since intercooler size, turbo size, etc will affect the volume of air in the system, thus affecting the pressure change. I'm not a scientist though so correct me if I'm wrong.
Ummm, what does his mod list have anything to do with my question? We were discussing how cold weather could increase boost due to the desinty of the air.
I know that aftermarket turbo kits have their own boost control. What I was asking was if his comment was referring to the factory boost control or if it was refering to something else.
Ummm, what does his mod list have anything to do with my question? We were discussing how cold weather could increase boost due to the desinty of the air.
I know that aftermarket turbo kits have their own boost control. What I was asking was if his comment was referring to the factory boost control or if it was refering to something else.
Boost is not the issue here. The colder air is messing up his warm weather tune. If anything he would lower the boost or change his tune.
Boost is not the issue here. The colder air is messing up his warm weather tune. If anything he would lower the boost or change his tune.
Why lower the boost if boost is not an issue?
I merely brought it up because it's a fact of life with turbo cars. I know that the temperature affects afr on it's own also, just pointing out that there's more than one thing to deal with here. Which you agree with from the above statement.
I merely brought it up because it's a fact of life with turbo cars. I know that the temperature affects afr on it's own also, just pointing out that there's more than one thing to deal with here. Which you agree with from the above statement.
either 1: Change your tune or 2: Lower the boost.
Both will give you lower A/F. That what I meant.
CPU boost control is what I meant about not being the issue.
Ok, here is what I was trying to get at. It was stated that boost does not go up and down like stockers with a big turbo. The fact is that it does indeed. The boost does not go up and down on a big turbo as a result of a boost controller, but rather as a result of air density. That’s all I was trying to say.
But on to the posters issue, yes, I agree, in cold weather, the boost should be turned down or the A/F richened up.
He (boost almighty) is trying to be proactive and set the A/F ahead of time. He is just going to have to watch his wideband and keep making adjustments accordingly. He can’t really go by a chart and look at weather forecast and say “oh, its supposed to be XX degrees today so I need to set the SAFC at XX”, and that’s what sayno2rice was getting at.
Last edited by wrcklsdrvrjim : 09-30-2005 at 04:09 PM.
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Temp. Affecting A/F Ratios??!!
Some things are pathetic! 
"straight clownin" 
This is not Photoshop
Linear Mode
