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we're in a cold snap here, and my intake temps are hovering around zero degrees. And the car is definitely, significantly quicker, and the AFMs are recording somewhat higher peak readings, so more air's getting stuffed into the cylinders. I've tweaked the fueling to keep things around 11.5:1, but I'm wondering...just how much more horsepower is freezing cold air worth?

Cause after the car settles in after spinning tires a bit and kicking the tail in 1st and 2nd...I've never had such smooth and strong pulls in 3rd and 4th (twin turbo pipe mod may be helping here). I'm hitting the 100mph mark a few tenths quicker for certain.

Ah, winter. More power (but how much more?)...and the damned tires won't stick to the road to use it when it REALLY gets cold!! :runaway:
 

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A popular (and published) rule of thumb for this is:
An increase of peak power by 1% for every 4 degree drop in temperature.

So your power is up by 6.25% assuming no change in atmospheric pressure.
 

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Intake temps at 0, you lucky bugger.

What are they peeking at under full sustained power, any idea?

We seem to be able to maintain around 10 deg's C under ambient (so around 15deg on a pretty warm day with the boost levels we've checked it at so far)

Rob
 

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for each 25degree less you get 1 point of octane less needed in fuel quality + the fact that you also have more air per a certain volume.. so your deffinatly making more power


now to tell you how much would be impossible without dyno testing but its a small gain that's all....
 

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A popular (and published) rule of thumb for this is:
An increase of peak power by 1% for every 4 degree drop in temperature.

So your power is up by 6.25% assuming no change in atmospheric pressure.
Is that on a turbo/intercooler system or just NA?

I have read in several auto-engineerings book that with turbo and intercoolers in place the difference in power from air temperature changes was very slight compared to the NA percentage diff.
 
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