Thin vs Thick Oil

I know that motors usually make a little more power with the thinner oils because of there being less friction and drag from the oil and parts. Has anyone ver seen a test done on this? I would like to see how much different a dyno sheet would look like with thin oil and then thick oil to see how much of a difference it is. If anyone knows of any videos on youtube about this or anything put the link to the video on here because I would like to see how much of a difference it is.
 
my engine builder says using his oil is worth a 10th of a hp shown on a dyno. his oil is slightly thicker than water lol. he is a very reputable builder
 
Use the least amount of the thinnest oil you can get by with without mechanical issues.
How much do you want to spend to find out?

Briggs flathead we could tell an on track difference between 13 and 14 oz of oil.(I think we used 13oz but it's been so long ago ???)
And a difference if we went to a thicker oil.

Tell the difference meaning racing on Sunday and practicing 3 nights a week was our dyno.

Snake oil? We never tried Turners "Motion Lotion" so I don't know bout that snake oil but I had my own snake oil additive I used tested many many times to be worth 200 rpm idle increase on the stand with no load except spinning the tires.
Always saved the possibility of using "Motion Lotion" for that special race, which never happened. ... :)

So does "Snake Oil" work?
answer: mine did

I've posted it's concoction on here many times.
Engine builder explained to me the biggest thing it probably did was decrease cylinder head volume and increase compression.
All I/we knew was it worked.
 
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Lighter weight oils with less parasitic drag will accelerate quicker.
Generally, with that, comes a trade-off of metal to metal protection.
With the flatheads and low compression, you don't need a heavy oil cushion for the bearings.
With the OHV stuff and higher compression engines, the heavier weight oil helps cushion the bearings considerably better and in my opinion is worth any "trade-off" in performance.
I've got stacks of papers and graphs from oil testing on flatheads 20+ years ago.
Today we recommend a lightweight oil for flatheads, and Briggs 4T or FHS 62R for all ohv or modified.


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Brian Carlson
Carlson Racing Engines
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For big races on my predator I would go down from my standard 14oz of 5w-20 to 12 ounces of 0w20 and could feel a difference. Also gained a few more RPM out of it like that as well. In these cases the oil was changed each time it hit the track as opposed to once per race day.
 
Thinner oil is also able to absorb and dissipate heat faster than thick. This is especially important to know when qualifying as most engines are taped up to get to temp faster. You want your engine to be as close to operating temp as possible for the money lap.
 
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