Synthetic oil, more power?

I posted a while back that I find that my saws run couple/few hundred rpm faster on 2T than dino oil (WOT, no load as measured by tach). Not quite as sure as compared to Ultra. I can't find that post or I would add this post to it rather than start a new post.

I am starting to be of the opinion that at least when it comes to bigger saws, they seem to get just a little more power using synthetic oil (2T) as opposed to dino.

I haven't done controls tests or anything (and I won't) but I think that I'm noticing this with my 7900s, 395, 880 and 3120. Okay heckle at will....

You have observed this with a tach???

To be sure, dump out the syn mix, and put dino mix back in, and see if it
drops. I am curious, but very skeptical. I do not heckle, just some
hardcore hazing.....

In terms of the WOT max rpm no load, I have run back to back tanks with my 7900s dino vs 2T and that was what got me to wondering about the rpm thing in the first place. Naturally there are alot of factors here, like the fact that with the dino I use pre measured oil containers and with the 2T I measure it. So it is possible that I am running more oil with the 2T which could make the saw run leaner, faster. I don't think this is the issue, but if I cared more (I don't) I could always measure both oils the same way and run back to back tanks.

In terms of the power, it's just a seat of the pants feeling. I have run back to back dino and syn tanks to see if it is reproducable, and I think I can feel a slight difference epecially with the 120cc saws. I don't really like to switch oils much (I don't know why, I just like to stick to one kind of oil), so I haven't really compared back to back very much. Plus dino smoke is stinkier so I generally just run 2T or Ultra (different saws, the Ultra has stabilizer so I run it in my saws that don't get run regularly).

I realize the power of suggestion is tricky, and it could be I am imaging the slight increase in power under extreme load with 2T. It's a happy feeling either way.

Well synthetic oil in minute terms is "slicker" than ash-based dino oil, but I'm not sure that the difference is that noticeable. I've taken apart saws that were run for ten years on dino oil and the engine components didn't look any different than saws run for ten years on synthetic. In fact, I have one customer who only runs Stihl 045 Super and 056 Magnum saws, which he bought brand new, and he runs 100 octane avgas with 60:1 full synthetic.

Now I can say for certain that when I changed my ATF from standard petroleum distillate-based Castrol to Royal Purple full synthetic, there was a noticeable difference. The truck shifts smoother and the transitions are easier.

I was wondering if somehow the synthetic had the rings sealing better under max load.

My main test cases were leaning on the 880 and 3120 (long bars) with enough force to try to stall the saws. Just seemed like the synthetic gave them a little more grunt.

Well I've read of tests where the full synthetic oil had 1.- More 'shearing' resistance under equivalent heat and pressure compared to dino oil, and 2.- Resisted combustion and chemical breakdown to higher temperatures than dino. I have no way of verifying those claims though.

Ben Walker where are you?

I feel that it has more to do with the fact that synthetic oil burns at a higher temperature than dino, this leans out the mix a bit causing the rpm's to jump, and if your like me I run my work saws a bit rich, so if you lean out the saw a little, it may make more power as well.

Could be just a bit less friction.
My van jumped up 4 mpg after using fully synthetic oil and it stays fairly clean over its 10,000 mile running time

I ran in my 660 on Stihl's mineral oil, then switched to Castrol synthetic. The difference "seemed" to be significant....better acceleration, more power etc

When I ran out I went back to the mineral oil, but didn't feel any reduction in performance. My bubble had burst

I wonder how much of a 'placebo' effect is going on?

It could be friction, but not because synthetic oil is slicker (it's not). Synthetic oil burns and separates differently than dino oil, so there may be more oil in the case lubricating everything, and reducing friction.

Jacob J. said:

I wonder how much of a 'placebo' effect is going on?

Click to expand...

Quite possible. A term that I think I recall is the Hawthorne Effect.

If so, at least I'm imagining more power rather than less. And the slight extra power under prolonged extreme load sure seems real enough.

B_Turner said:

Quite possible. A term that I think I recall is the Hawthorne Effect.

If so, at least I'm imagining more power rather than less. And the slight extra power under prolonged extreme load sure seems real enough.

Click to expand...

I say both to any poor girl that buys it...................................

Has anyone noticed if a new saw takes longer to break in when using synthic oil.I now in new cars it's not good to run it,because the parts don't breakin properly.Iv'e also been told it's not good for rollerbearings,like rollerrockers as it's too slippery and causes flat spots on the rollers.Instead of rolling,they slide.Any thoughts on that.

slabmaster said:

Has anyone noticed if a new saw takes longer to break in when using sint. oil.I now in new cars it's not good to run it,because the parts don't breakin properly.Iv'e also been told it's not good for rollerbearings,like rollerrockers as it's too slippery and causes flat spots on the rollers.Instead of rolling,they slide.Any thoughts on that.

Click to expand...

Old wives tales. The only negative thing synthetic oil can do is cause old engines to leak.

Where's, Gary ask him he will know.:hmm3grin2orange: :hmm3grin2orange:

Jacob J. said:

Well I've read of tests where the full synthetic oil had 1.- More 'shearing' resistance under equivalent heat and pressure compared to dino oil, and 2.- Resisted combustion and chemical breakdown to higher temperatures than dino. I have no way of verifying those claims though.

Click to expand...

I really doubt that there's any significant difference in the saws. Maybe slight but not much. Where that shearing resistance comes into play is in an application such as a motorcycle that shares engine and transmission oil. The polymer chains get sheared in the meshing tranny gears and breakdown faster. I run Mobil 1 in my bikes for this reason.

B. Turner, get your wife to fuel the saws for a blind test to see if you can tell which is which you are burning. I agree about the power of suggestion easily being greater than the mechanical difference.

There are synthetic oils that are rated, tested and provable to give better mileage in road vehicles. If there is less friction it could have an effect on a saw but it sure complicates matters when it is being at least partially burned; also the effects possible on produced fuel to air mixtures have an influence on power output. If it is clearly the case that more fuel efficiency can be had with synthetics, I would think its manufacturers would be shouting it out: however if they are making more profit on the dino stuff they wouldnt bother.

Synthetic oils having less friction is largely a old wives tail.
Different oils combust differently and can causing tuning variations, ditto with different fuels.
And I wouldn't bet a dime on a synthetic oil boosting HP....