Detonation in the winter?
Guest
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Detonation in the winter?
Took the mustang out for the first time in a couple of weeks tonight (its been raining on my days off and I'm on slicks). The car felt good exept for only having about 5psi in the tires (but I took a dramamine so I'm ok now). Only issue was I could hear detonation at the top of 4th gear. I didn't throw the laptop on it to do any datalogging, but I was just trying to run through my head why it would detonate in low 50's weather when it was fine in the mid 70's. The only thing that's changed is the headgasket a while back. Is it possible that I'm on the ragged edge of the tune and the added density of the air is causing a lean condition? I would think the TEC would compensate for that but I'm asking the "experts" 
Pull Over
Joined: Aug 2001
Posts: 924
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You should just ask Dr Dirt about what weather changes can do to a tune. If you are close or if your compensation is not working on your TEC then the weather can make a change. Also how long has the car sat with this batch of fuel?
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"I'm in the 82nd Airborne and this is as far as the bastards are going!"
93 Cobra, R302 331,canfields,T-76,TKO......sold
87 Coupe, 466, Edelbrock heads,Vic jr,150 shot 10.41@129.5...sold
2006 Honda 450ER .....new toy
Do you own a Torch Red FRC and tremble every time you drive under I75 on Hwy 60 and look in your rearview mirror? If so you are suffering from what is known as Cobraphobia.
"I'm in the 82nd Airborne and this is as far as the bastards are going!"
93 Cobra, R302 331,canfields,T-76,TKO......sold
87 Coupe, 466, Edelbrock heads,Vic jr,150 shot 10.41@129.5...sold
2006 Honda 450ER .....new toy
Do you own a Torch Red FRC and tremble every time you drive under I75 on Hwy 60 and look in your rearview mirror? If so you are suffering from what is known as Cobraphobia.
Team Geritol Racing
Joined: May 2001
Posts: 5,759
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Originally posted by race495
You should just ask Dr Dirt about what weather changes can do to a tune. If you are close or if your compensation is not working on your TEC then the weather can make a change. Also how long has the car sat with this batch of fuel?
You should just ask Dr Dirt about what weather changes can do to a tune. If you are close or if your compensation is not working on your TEC then the weather can make a change. Also how long has the car sat with this batch of fuel?
Throw some octane at that puppy. It's cheaper than a new engine. 
Guest
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Originally posted by Scott
No way !
EFI can't go out of tune with weather changes !
How about some shitty gas or water in the fuel ?
No way !
EFI can't go out of tune with weather changes !
How about some shitty gas or water in the fuel ?
Don't worry Scott, we'll convert you yet! We'll slip some roofies in your beer one night and order you a fully sequential wide band FAST system with all the goodies with your credit card
Registered User
Joined: Dec 2002
Posts: 4
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My car does the exact same thing when the temp drops down low. I just try to stay out of it as much as I can. I also notice the boost builds a little quicker when it really cold.
