Leaner with warmer outside temp??
04-08-2010, 12:19 PM
#1
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
Leaner with warmer outside temp??
I had the car out three months ago when it was 40*. I took it out two weeks ago when it was 65 and it went lean by a full point. Lost power too. Nothing was changed except a bigger s/c pulley to lower boost a little until I get it properly re-tuned again.
I'm using a blow through mighty demon and 9psi. I even have some meth added to the mix and my rear jets are 97. A few months ago, it was perfect at 12.9:1, now its like 13.8-14.2. Meth is working. Power does drop so its not a sensor or gauge fault. This crappy barry grant can't be THAT inconsistent can it?
I'm using a blow through mighty demon and 9psi. I even have some meth added to the mix and my rear jets are 97. A few months ago, it was perfect at 12.9:1, now its like 13.8-14.2. Meth is working. Power does drop so its not a sensor or gauge fault. This crappy barry grant can't be THAT inconsistent can it?
04-08-2010, 12:23 PM
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Car: Trailblazer EXT 4.2 (Firebird Form)
Engine: 5.1 4bbl
Transmission: 700R4 Mega Raptor Level 4
Axle/Gears: 2.73
Re: Leaner with warmer outside temp??
yes it can ... have you ever turned to a drag racing show on TV... the first thing they say, TODAY WHAT A PERFECT DAY FOR RACING... nice and cool.... I would say yes it can affect the performance...
04-08-2010, 12:27 PM
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
Re: Leaner with warmer outside temp??
Yes cooler air is good for performance, I'm wondering why a 25* (roughly) would give me an afr fluctuation of more than a full point. I don't think that is normal, this is dangerous and I'm wondering if I should be looking for a problem.
04-08-2010, 06:37 PM
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Car: 89 IROC-Z
Engine: 370 LSX, LS3 Top End
Transmission: Built T-56
Axle/Gears: 9" Aluminum Center 3.89's
Re: Leaner with warmer outside temp??
Its leaner when its colder (denser air), and richer when it's warmer (less dense).
That's why dumbasses who don't re jet their sleds when its 0* out melt them down
That's why dumbasses who don't re jet their sleds when its 0* out melt them down
04-08-2010, 07:32 PM
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
Re: Leaner with warmer outside temp??
Sigh.
Correct again thank you. That is why I post this question. IT IS LEANER WITH WARMER TEMPS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Don't read what you want to read, read what I posted. Some people might call one a dumbass for not being able to properly read the only language they are fluent in.
Correct again thank you. That is why I post this question. IT IS LEANER WITH WARMER TEMPS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Don't read what you want to read, read what I posted. Some people might call one a dumbass for not being able to properly read the only language they are fluent in.
04-09-2010, 10:54 PM
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Car: 89 IROC-Z
Engine: 370 LSX, LS3 Top End
Transmission: Built T-56
Axle/Gears: 9" Aluminum Center 3.89's
Re: Leaner with warmer outside temp??
Sigh.
Correct again thank you. That is why I post this question. IT IS LEANER WITH WARMER TEMPS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Don't read what you want to read, read what I posted. Some people might call one a dumbass for not being able to properly read the only language they are fluent in.
Correct again thank you. That is why I post this question. IT IS LEANER WITH WARMER TEMPS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Don't read what you want to read, read what I posted. Some people might call one a dumbass for not being able to properly read the only language they are fluent in.
Read my post, cold air is denser than warm air, so when it's warmer it should be fatter. You're saying that the a/f was leaner when the air temp increased...which doesn't make any sense to me.
04-09-2010, 11:27 PM
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Car: Trailblazer EXT 4.2 (Firebird Form)
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Transmission: 700R4 Mega Raptor Level 4
Axle/Gears: 2.73
Re: Leaner with warmer outside temp??
CHILDREN, do you two need a timeout? 
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04-11-2010, 10:29 PM
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
Re: Leaner with warmer outside temp??
It doesn't make any sense to me either, so I'm looking for some clues as to why. I got a tip that it could be a fluttering power valve.
You stated the reason I made the post. Many people are quick to spout/show off what they know without ever stating any relevant information. I just have a low tolerance for that, I'm sorry if its a fault. A little.
You stated the reason I made the post. Many people are quick to spout/show off what they know without ever stating any relevant information. I just have a low tolerance for that, I'm sorry if its a fault. A little.
04-12-2010, 12:21 AM
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Car: 89 IROC-Z
Engine: 370 LSX, LS3 Top End
Transmission: Built T-56
Axle/Gears: 9" Aluminum Center 3.89's
Re: Leaner with warmer outside temp??
Sorry about that, my bad. I assume the fuel pressure is the same, and wb sensor is good too. How big of a valve do you have in it now?
04-12-2010, 08:46 AM
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Car: 91 rs
Engine: Blow through 383, 10 psi, xr288hr
Transmission: Manual th350 ATI 3000
Axle/Gears: 3.50 9"
Re: Leaner with warmer outside temp??
I have a 6.5 in it. I pull around 13" of vacuum. I had a 5.5 in it and I had a rich cruise, so I went a little higher. The problem went away for a while but the car is rich on cruise again and lean at WOT. It really does sound like a powervalve. I'll have to pull it out when I get a chance.
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