SteveIAS8

I was reading a message you posted back on 9-29 regarding running 0-30rMobil oil, and noticed a huge jump in MPG, and was trying to figure out if a 26HP was justifiable.

Did you ever figure out if this was correct?

Steve

ryoung

Snce the <A HREF="https://forums.audiworld.com/a8/msgs/75960.phtml">Original Post</a>, I repeated the MPG test with the exact same results. With 300+ views, there's been no criticism of the calculations. BTW, I was impressed with the 21.3 mpg at 73 mph; at 63 mph I've been getting 23+ mpg, something else I've never seen before with the S8.

I'm sure that the previous racing oils used in NASCAR were also low friction, but I can understand why most teams are now using the Mobil 1 0w-30R. [Unlike many high strung race motors, NASCAR motors only run at 10,000 rpm max.] Another observation -- there's no reason at all for a multi-weight racing oil, a straight 30w oil would be fine. I'm sure that oil this is offered as a 0w-30 to encourage it's use in "normal" cars.

SteveIAS8

I'm good at math, but I'm not good at these types of formulas, so forgive me if my thoughts or questions appear naive:

1- to me, it's just too incredible to believe that a change in oil can boost HP 7.2% over factory.

2- (now this might be the foolish question...) is it possible that the reduction in friction simply moved the HP curve lower down the RPM curve, and just made the HP available sooner? did it actually "increase" HP? The reason why i ask this is that i remember watching one of those car shows and they talked about something similar- frees up HP, just did not increase HP. I could be interpreting this wrong.

3- I have a 2001 S8, and i run frequently between Des Moines and Minneapolis, and i can run at 74mph and average 22.4 both ways. Was it the oil change that did it for you? possibly something else?

4- Have you put it on a dyno to see what the machine says?

5- 300+ views, to me, simply means that people like to hear what you say. It appears that your knowledge in this area is far superior to most ( don't take this the wrong way, everyone-- he just knows his stuff...)

I am really interested in this, becasue i would like to do the same. BTW, how much is a quart of this liquid gold?

Thanks!

Steve

ryoung

1. In the dyno pulls in <A HREF="http://www.performanceoilnews.com/oils_against_oils.shtml">Oils agains Oils</a>, HP varied by 5.5% from best to worst of the 11 oils tested, and none were racing oils specifically designed to be low friction. A 7.2% gain for a low friction racing oil seems very reasonable.

2. You're right, it's "freeing up" HP, not making more. Though since friction is proportional to speed squared, the gains would be largest at max rpm (where HP peaks also). HP that had been "wasted" as friction and just heats up the radiator coolant is now "freed up" to turn the crankshaft.

3. Without a tailwind, I had never seen 22 mpg at speeds &gt;70 mph; on the better days I'd see 20.0 mpg. I have no idea why are '01 S8's are different.

4. Unfortunatley, I haven't seen any dyno tests of Mobil 1 0w-30R versus anything. I am absolutely certain, though, that NASCAR teams use it for only one purpose ... HP.

5. Thanks for the complement :-)

6. Cost on the Internet varies from $6-8/qt. I've never seen it on a store's shelf.

AUDIrageous

In OH &amp; MI area Murry's Auto Parts stocks it @ 7.49 ea.

SteveIAS8

Thanks, randy, for the info!

HZach

Since the goal is to reduce friction, would it be advantageous to use an oil additive like Slick 50 to coat the engine internals with PTFE?

ryoung

since they're never used in race motors (just being pragmatic). In addition, I wouldn't be enthusiastic about a solid additive that could potentially settle out and restrict flow in the many small oil galley's.

JimR

I stopped in at an Acura dealer to look at the new RL yesterday (no, not interested, other than in a "generally interested in cars" way; I was right next door anyway, for a lunch meeting, and a friend works at the dealership).

The oil cap says 0W-20!!

Clearly Honda likes thinner oil.