I had something happen today that I've heard others talk about from time to time but I'd always just chalked it up to placebo effect: I changed my oil and felt more power afterwards. The oil was (3 qts.) Mobil 1 0W-40 + (1 qt.) Mobil 1 0W-30R.

 

OK, I know what your thinking, but I've owned dozens of cars and have done several dozen oil changes on each of 'em. In the process I've tried just about all the common oils (Pennzoil, Castrol, Quaker State, of various weights, some synthetic & some conventional, Delvac 1300S, and just about every Mobil 1 product, but I've never really "felt" any difference between any of 'em other than the thick oils tended to make the worn engines quieter and keep the oil pressure up at lower revs.

 

This was apparent. I'm guessing 3 ft. lbs of torque.

 

The reason for the (1 qt.) of 0W-30R (race) was to cut the viscosity a little and beef up the add-pack. The R oil has a stout anti-wear add-pack.

especially under cold conditions like you have. I suspect it might not be so noticeable around here where the weather is mild. In Maine when it was really cold you could easily tell when you had just put light oil in the tranny of an underpowered car. It was so easy to tell because the car would stall before first time you let up the clutch in the AM, and would actually run afterward.

You could also really tell a change of crankcase oil when the car would crank much faster witn new light oil. Stands to reason you could feel that drag until it warmed up anyway.

I just put Mobil 1 in my BMW and am considering putting it in my Subie. It really feels and acts different. If I pull the dipstick the stuff falls off faster than I can get a rag under it. The BMW syn just sat there on the stick. That seems like it has to translate to a bit more power and less drag.

I had something happen today that I've heard others talk about from time to time but I'd always just chalked it up to placebo effect: I changed my oil and felt more power afterwards. The oil was (3 qts.) Mobil 1 0W-40 + (1 qt.) Mobil 1 0W-30R.

 

OK, I know what your thinking, but I've owned dozens of cars and have done several dozen oil changes on each of 'em. In the process I've tried just about all the common oils (Pennzoil, Castrol, Quaker State, of various weights, some synthetic & some conventional, Delvac 1300S, and just about every Mobil 1 product, but I've never really "felt" any difference between any of 'em other than the thick oils tended to make the worn engines quieter and keep the oil pressure up at lower revs.

 

This was apparent. I'm guessing 3 ft. lbs of torque.

 

The reason for the (1 qt.) of 0W-30R (race) was to cut the viscosity a little and beef up the add-pack. The R oil has a stout anti-wear add-pack.

I am impressed by the sensitivity of your "butt dyno".

The real dyno seems to support your observation.

See this study on 0W40:

http://www.performanceoilnews.com/oils_against_oils.shtml

especially under cold conditions like you have. I suspect it might not be so noticeable around here where the weather is mild. In Maine when it was really cold you could easily tell when you had just put light oil in the tranny of an underpowered car. It was so easy to tell because the car would stall before first time you let up the clutch in the AM, and would actually run afterward.

You could also really tell a change of crankcase oil when the car would crank much faster witn new light oil. Stands to reason you could feel that drag until it warmed up anyway.

I just put Mobil 1 in my BMW and am considering putting it in my Subie. It really feels and acts different. If I pull the dipstick the stuff falls off faster than I can get a rag under it. The BMW syn just sat there on the stick. That seems like it has to translate to a bit more power and less drag.

 

Well, this isn't my first time using Mobil 1, just the first time trying the 0W-40 grade. I've tried Mobil1 10W-30 in the summer and Mobil 1 5W-30 in the winter in this same car. It's good oil, but always seemed to have a harsh, "rattly" quality to it.

 

Now both those oils have lower kinematic vicosities at warmup (40*C) and operating temperature (100*C) than the 0W-40 does, and both also have a lower HTHS viscosity than the 0W-40. Apparently there's some other significant dynamic condition to motor oil performance that affects drag other than these standardized comparators.

 

Also 2 of the qts. that I used didn't even have the "Energy Conserving" on the back 'cause they're several years old (the current stock has it). I excitedly bought several quarts of this stuff when it first came out, but was a little reluctant to use it, so it's been sitting around.

I am impressed by the sensitivity of your "butt dino".

The real dino seems to support your observation.

See this study on 0W40:

http://www.performanceoilnews.com/oils_against_oils.shtml

This car is extremely consistant in regards to power and feel, so it's easy to detect changes, plus my daily work involves making subjective judgements (in audio nontheless), so I have a mindset tuned to zeroing out personal biases in situations that require it (I think that's why I tend to go overboard with personal opinion "off duty"). :-\

 

I had run several errands early in the morning, needed to do an oil change (in 21*F), jumped back in to do finish a few more errands and noticed the power, just like that. I wasn't looking for it. Wasn't expecting it. Never experienced it before.

 

That link seems to match what I felt. I didn't even have the opportunity to rev the motor out (traffic). The torque increase I felt was just in the midrange 3-4000 RPM. I 'spose there's more on top. A friend of mine who assembles lease engines at Maclaren did tell me about a year ago that they fill the motors with Mobil 1 0W-40 for dyno test and before they shop 'em out. So the puzzle comes together.