I don't remember who it was that posted a 0-60 time of 7 seconds flat for a new S40 but I do remember giving him a really hard time about it.

I need to apologize for that. Sorry.

The car: 2001 Volvo S40, Torch Red, Tan interior, loaded.

The mileage: 4400 miles

The conditions: around freezing, clear skies

The gas: 92 octane

The procedure: left foot brake, right foot gas to 2000 RPM, DSA off.

The 0-60 time: 7.65 seconds, bone stock on SNOW TIRES!!!

Intake added: 7.30 seconds ON SNOWS!!

Gimmie some grip and I'm sure I'll make better numbers on summer rubber. I stand corrected my friend. This is one helluva a quick little car considering the engine size and such. Volvo needs to rethink their 8.5 second estimate BIG TIME!!

it was me,ryan t.i would have been questioning me too.to answer a couple of the questions,it was in the mid 30 degree range when i made those runs.i used 93 octane gas,an interesting thing on the gas,i noticed a .3 second difference in brands of gas even though they were all 93 octane.i put some octane booster in it and dropped to 6.8 second 0-60.when i launched at 2000 rpm i had wheel spin.my best was at 1500 rpm launch(tires,weather,who knows)just glad to see someone else doing some testing

ryan t wrote:

> it was me,ryan t.i would have been questioning me too.to answer a

> couple of the questions,it was in the mid 30 degree range when i made

> those runs.i used 93 octane gas,an interesting thing on the gas,i

> noticed a .3 second difference in brands of gas even though they were

> all 93 octane.i put some octane booster in it and dropped to 6.8

> second 0-60.when i launched at 2000 rpm i had wheel spin.my best was

> at 1500 rpm launch(tires,weather,who knows)just glad to see someone

> else doing some testing

I was launching at 2000 RPM. Very slight wheelspin with snow tires. I too was using 93 octane. I also had a little extra weight in the trunk that I'll be sure to remove next time I try this. This little car is actually quite quick all things considered!

Congratulations. Just a thought: you do have your speedo calibrated, don't you, so that the 60 mark is not optimistic?

John R wrote:

> Congratulations. Just a thought: you do have your speedo calibrated,

> don't you, so that the 60 mark is not optimistic?

Not sure what the speedo said. The radar gun did most of the talking. I have some REALLY good friends in law enforcement.

The only thing that can "discredit" the, indeed, incredible low 7s time is the cold weather. Engines will generate more power under "almost freezing" conditions rather than at, say, 60 degrees or so.

Yannis

Yannis,

Why would engines generate more power under "almost freezing" conditions?

Sid

The colder the ambient air your engine "breathes," the more dense it is...hence more oxygen per cubic area. The single most limiting factor to any internal conbustion engine is the ammount of oxygen (air) you can get into it. NOS, supercharging, and turbocharging all work with this principal in mind.

Andrew

2000 Red V40

Austin, Tx

Thanks for your answer. One more question: Is there a "specific temperature" that oxygen could no longer condense or the extremely low temperature would start to diminish the effect of oxygen condenstaion? If so, wouldn't it be the "perfect temperature" for car racing or performance testing?

Sid wrote:

> Thanks for your answer. One more question: Is there a "specific

> temperature" that oxygen could no longer condense or the

> extremely low temperature would start to diminish the effect of

> oxygen condenstaion? If so, wouldn't it be the "perfect

> temperature" for car racing or performance testing?

-182 degrees Celcius. Anything lower and it becomes a liquid. Good luck getting the engine to turn over though.

> -182 degrees Celcius.

This is not the question I asked about...

>Good luck getting the engine to turn over though.

That's the question I asked about... I believe that extremely low temperature must have some negtive effect to the engine performance. So I don't believe that "the lower the temperature, the better the performance" is always true all the way down to -182 degree Celcius. I was asking about if there's a "perfect point" that would balance the temperature and oxygen condenstaion effects to the engine?

-182? I don't think we are talking about a rocket.

I have driven my S40 threw 117+ F on the Temp gauge in Houston to around 3 F in Kansas. I have always notice my peak power to be had in temps around 65F on a nice sunny day! I guess it could be due too High pressures caused by nice weather!

This is really an interesting discussion. There is probably an ideal opearting point. What I mean is that there is a temperature low enough where the engine is producing a greater power than the increased drag caused by the cold air. Therefore, there should be a temperature where the difference between the power generated and the drag is greatest. I don't know what it is.

There is also the question of humidity. I have to believe that this has an influnce on the traction, therefore the amount of power that can be laid down.

This would make a good science project for a 'kid'. Imagine, '0-60 times vs. ambient temperature/humidity/barometric pressure'!

> This would make a good science project for a 'kid'. Imagine, '0-60

> times vs. ambient temperature/humidity/barometric pressure'!

Well, this might be a good project for car magazines instead of 'kids.' :)

Does colder air move slower than warm air? I havn't taken any fluid or gas dynamics classes yet... but I wonder, is drag reduced by cold air significantly?

Also regarding humidity: I would think it would interfere more with combustion, rather than traction, as concrete vs. asphalt at the track would be a more varing factor for traction... no?

Andrew,

2000 Red V40

Austin, Tx

> Does colder air move slower than warm air? I havn't taken any fluid

> or gas dynamics classes yet... but I wonder, is drag reduced by cold

> air significantly?

Once you get to your Fluid mechanics class you will learn that temperature has a strong effect and pressure has a moderate effect on viscosity (look at your motor oil). You can approximate the this phnomenon with the Sutherland law. Drag is therefore INCREASED with cold weather. It has nothing to do with the speed of the air, cold air can move just as fast as warm air.

I think that you are probably right about the humidity though.

It seems that you would need to have the temperature low to 'condense' oxygen, or you could carry liquid oxygen like the space shuttle. Maybe 'condense' is not the right word for your question. I don't understand what you are tring to ask.