What a Cool Weather Streak and Amsoil Might Do

[Moto-Mojo]

I may be suffering from performance delusion, but the weather brought some cold (dense) air to NorCal this weekend and I also changed to Amsoil too. The ol butt dyno picked up 5.45678431856 more horsepower. But I could be slightly off!

Seriously, there was a noticeable difference.

[SS Performance]

I've been using Amsoil for years in everything from street rods to commercial trucks.

In just about every instance I have seen an increase in fuel economy. Which should also mean an increase in power.

That being said a cold snap could also result in more power.

[Moto-Mojo]

I mentioned in another thread the other day my 15.1 avg MPG. I drive it like it should only get 15.1 and am happy with that but, I will be curious if the Amsoil improves on that at all. I’ve been a long time fan of Amsoil but it just got harder to find.

Yes, the LS seems to thrive on cold, dense air.

[DonM]

I know when I switched from DEXOS to AMSOIL, I gained a couple of MPG

[jimmyp]

That Cool Air makes everything run great, you can really feel it on bikes.

[SlingShot]

What's cool air, we are a couple months away from any type of cool air. I can tell if the weather is good for cars by then way the cold water in the house feels. During our summer months our cold water is warm (90-95) degrees. Both of my cars feel so good during the 70 degree weather, especially the ZL1.

[Greenhornet2]

It's the cool air. Nothing to do with oil. hot humid compared to cool dry air will make a huge difference. I feel it in my car no doubt easily 5-10% difference. It also makes me lose traction with the cooler roads so it makes it hard to tell sometimes.

[Moto-Mojo]

Those of you who have had older performance cars, could you feel it in those? Or is the LS somehow more able to take advantage of cooler air with its better flow characteristics?

[Rock-It Man]

Originally Posted by Moto-Mojo

Those of you who have had older performance cars, could you feel it in those? Or is the LS somehow more able to take advantage of cooler air with its better flow characteristics?

First of all, cold air is denser, so you get more oxygen molecules into each charge. And with modern engines, the O2 sensor will cause the injectors to add more fuel to that larger charge to achieve a stoichiometric ratio. This results in more power. So you will get the same effect with any "modern" car, and by that I mean any car that has electronic fuel injection.

Even with a carb engine, there's some power increase when the air density increases, but you would have to be adjusting the carb and changing jets to take full advantage of the denser air.

[Moto-Mojo]

Originally Posted by Rock-It Man

First of all, cold air is denser, so you get more oxygen molecules into each charge. And with modern engines, the O2 sensor will cause the injectors to add more fuel to that larger charge to achieve a stoichiometric ratio. This results in more power. So you will get the same effect with any "modern" car, and by that I mean any car that has electronic fuel injection.

Even with a carb engine, there's some power increase when the air density increases, but you would have to be adjusting the carb and changing jets to take full advantage of the denser air.

Interesting. I’ll take that as a yes, the LS and its modern pedigree does indeed compensate better than a ‘69 Z/28 for atmospheric changes. Damn car is so smart I may ask to marry it! But I might have to move to UT.

[christianchevell]

In the old days you would turn 1/4 turn to 1/2 turn on the enrichment screw of your carb to make use of the denser air by less restriction in the jets pathway and allow more power.

Colder air is always better for making power especially with forced induction etc....

[Rock-It Man]

Originally Posted by Moto-Mojo

Interesting. I’ll take that as a yes, the LS and its modern pedigree does indeed compensate better than a ‘69 Z/28 for atmospheric changes. Damn car is so smart I may ask to marry it! But I might have to move to UT.

It's not because of improved flow, but because of improved engine control to take advantage of basic physics and chemistry; something you will find in the most lowly car today.

[Moto-Mojo]

Originally Posted by Rock-It Man

It's not because of improved flow, but because of improved engine control to take advantage of basic physics and chemistry; something you will find in the most lowly car today.

But I know I’ve read more than once about the increased flow in these motors. Not that I dispute the ECM’s ability to do things like “turn the air/fuel screw” electronically, much better than our old, human feeble attempts to do those things long ago. I guess it’s a combination but a 20 degree temp drop made a noticeable change.

[15RS2NV]

January is our coldest month here in southern Arizona, so that's when i run my fastest times. 60* at the track is good to me. And, yes, it's 60 in January. Don't hate! LOL