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Anyone good at math?

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I was going to make a graph of the 2 stroke HFRR at different ratios. From this http://mopar.mopar1973man.com/cummins/general/2-cycle-oil/hfrr/hfrr.htm I know that 2 stroke at 200:1 is HFRR 474 and regular #2 is 636. So I can do some generalizing and figure out a formula by using the 162 difference between the two HFRR's, I can say that 400:1 would have an HFRR with a difference of half that, so 162/2=81, 636-81=555. Now that you know how I have it calculating, I will show you the stats and you can see the issue I run into at the bottom.

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  • Owner

But remember the test results from DieselPlace was using untreated diesel which scored at 636 HFRR then typical pump diesel should score ~520 HFRR typically. But I've got a feeling that when you look at it from a general point of view. You take like my 17 year old Sthl Chainsaw that is running on 50:1 ratio of 2 cycle oil and GASOLINE. It still got 130 PSI of compression. So looking from a general point of view at 50:1 there should be a score of roughly 0 HFRR because there there was a number above zero then my chainsaw should of wore out long ago...

  • Author

We can't use 520 because it wasn't part of the test. I am trying to get this thing working based on what they used for the test, after I get it to work, then I can put in 520. The formula is supposed to be exponential from what I can tell but I don't know how to make that work. The fact that the bottom ones are all messed up makes me think all the rest of the calculated values are messed up.

Does anyone know the HFRR of 2 stroke oil itself and not in combination with diesel fuel. Also, what is the best HFRR for our trucks?

  • Owner

Yes I can answer that... Bosch already did the testing on VE, VP44, and CR fuel systems... post-2-138698172142_thumb.jpg And there results are anything under 450 HFRR is safe... There full document is here. http://forum.mopar1973man.com/downloads.php?do=file&id=1 So using Diesel Place test results anything under 400 HFRR is good... http://mopar.mopar1973man.com/cummins/general/2-cycle-oil/hfrr/hfrr.htm But remember todays fuel is suppose to contain some lubricant about ~520 HFRR is typical number... But remember I'm running 128:1 ratio so the HFRR is below 400 HFRR in theory...

I am using the Diesel Place numbers because they are known. I am using your ratio calculator to find the numbers. I have done similar calculations and came up with similar numbers. In order to get under the 450 HFRR the mix needs to be about 173:1. At 128:1 the value is 383 HFRR. Now, using ~520 HFRR as the baseline, and using Diesel Place's formulary, using the knowns of 636 HFRR/0 and 474 HFRR/200:1 to infer all other numbers, a ratio of 500:1 gets a 455 HFRR with my calculations. Extrapolating from that, at 128:1 would be about 267 HFRR. So, if I went to running 256:1 ratio, i.e. 1 gal : 0.5 oz, 2 gal : 1 oz, or 32 gal : 16 oz, the number would be about 393 HFRR. Still below what is recommended.Still using the ~520 HFRR, the 200:1 would be about 358 HFRR. I am inferring that anything below 60:1 ratio is not better for the engine, i.e. does not help. [ATTACH]2069[/ATTACH] Now, according to this graph, the ideal mixture is 175:1, at a HFRR of 636. This brings the HFRR to 450.4555556 or 451. And according to the Bosch study, 450 is acceptable. Please remember this is all in theory, I will be resting for a few, my brain is strained. I enjoy the ease of 128:1, i.e. # of gallons = # of ounces of 2 stroke.

2 Stroke graph 33.xlsx

  • Owner

My thought on 50:1 with gasoline is that if my chainsaw still has good compression after 15+ years of service then I know that 128:1 against diesel should be darn close to zero wear... But the only way to test that is some have a HFRR test rig... As for my calc program it was using the infromation from the diesel place testing everything is spits out is in theory... :rolleyes:

I used the calc program to compare to mine and got similar results. All in theory....... I am unable to purchase the HFRR testing gear, due to monetary constraints, i.e. I can't even pay attention:lmao:.

  • Owner

I used the calc program to compare to mine and got similar results. All in theory....... I am unable to purchase the HFRR testing gear, due to monetary constraints, i.e. I can't even pay attention:lmao:.

I know the feeling most times... :broke:

UMMMMMM!!! I feel I'm a fairly smart man and can just about figure anything out, But What the HECK are ya'll Talking about????????????????????????????????????????????????????? He He HE!!!!!I know it's somthin anout Slickum in Diesel and addin some more by usin 2 Stroke oil, But this HRFF HFRR crap ya'll got me lost!!! Sorry can some of ya speak EnGRISH please??? LOL

Ummmmm, let's see!!!!!! Gonna make it slicker, and not waste $$. :smart:Don't use too much slickum', more $$ gone. :smart:More $$ gone, no upgrades!! :cry::cry:

  • Owner

Here is a learning curve for ya...

http://www.eng.wayne.edu/page.php?id=4971

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Lowering sulfur levels in diesel fuel is one of the methods to reduce exhaust emission of diesel engines. Prior to October 1993, the diesel fuel that was sole in the usa had a sulfur level of approximately 5000 ppm. In 1993 the EPA mandated that all diesel fuel sold in USA contain 500 ppm or less sulfur. On June 2006, the EPA again lowered the level of sulfur in petroleum diesel fuel. The new standard is 15 ppm.

The need to reduce the exhaust removes sulfur and significant amounts of polar and aromatic compounds that give conventional diesel fuel adequate lubricating capability. Low lubricity in diesel fuel can cause engine problems unless treated with additives.

Measurement of diesel fuel lubricity characteristics is important in order to monitor lubricity additives and final fuel quality. Engine manufacturers need a quick, dependable, cost effective solution to predict fuel lubricity. HFRR is one such test to measure the lubricity of fuels.

HFRR and SLBOCLE are two methods for evaluating diesel fuel Lubricity. HFRR is capable of rubbing a steel ball loaded with 200 g mass against a stationary steel disk completely submerged in a test fuel at 60 C. The apparatus uses a 1-mm stroke length at a frequency of 50 Hz for 75 min. After 75 minutes of test time, the ball is removed from the vibrator arm and cleaned. The dimension of the major and minor axes of the wear scar are measured under a microscope and recorded as HFRR wear scar diameter. Higher the lubricity smaller the wear scar diameter.

:neutral::neutral: UMMMM! :banghead::banghead: (Mopar):nadkick:(Jgendr) :surrender:( did you see the Light com on) :lmao::lmao::lmao: Oh!!!! I get it now :wif: means :wts: untill you get new :fuel: ROFLMAO!!!

Funny... :lmao2::lmao: Naw... Just means to put alittle extra dope in the fuel... :thumbup2:

I heard they are supposed to add lubricative additives at the refinery to bring the lubricity down to where it needs to be? http://www.deere.com/en_US/ag/servicesupport/tips/tractors/common_stories/ultra_low_sulfur_diesel_fuel.html# Generally speaking, the same oil refinery process used to reduce Sulfur content also removes Oxygen, Nitrogen, aromatic compounds, and other key characteristics in diesel fuel, which are considered to be natural fuel lubricity agents. Sulfur content by itself has little to do with fuel lubricity. Many oil refineries are now adding back in other fuel lubricity agents to prevent the former diesel fuel lubricity and rubber seal deterioration fiasco experienced back in 1993 and 1994. Reducing the sulfur content of diesel fuel from 500 ppm to 15 ppm will have no significant effect on engine fuel economy, fuel density, fuel heating value, or fuel lubricity. For your reference, here are the current and future government regulations addressing diesel fuel Sulfur content in the United States and Europe.

I heard they are supposed to add lubricative additives at the refinery to bring the lubricity down to where it needs to be? http://www.deere.com/en_US/ag/servicesupport/tips/tractors/common_stories/ultra_low_sulfur_diesel_fuel.html# Generally speaking, the same oil refinery process used to reduce Sulfur content also removes Oxygen, Nitrogen, aromatic compounds, and other key characteristics in diesel fuel, which are considered to be natural fuel lubricity agents. Sulfur content by itself has little to do with fuel lubricity. Many oil refineries are now adding back in other fuel lubricity agents to prevent the former diesel fuel lubricity and rubber seal deterioration fiasco experienced back in 1993 and 1994. Reducing the sulfur content of diesel fuel from 500 ppm to 15 ppm will have no significant effect on engine fuel economy, fuel density, fuel heating value, or fuel lubricity. For your reference, here are the current and future government regulations addressing diesel fuel Sulfur content in the United States and Europe.

Believe it or not sulfur is actually a major factor in lubricating potential. Remember that the system used in diesels engines operates under HIGH pressure and sulfur is used just for that. A high pressure lubricant. Pay attention the next time you buy grease and you will notice Molybdenum disulfide. It also shows up in many other lubricants. Also as far as sulfur and fuel mileage you are right. There is no noticeable effect due to the sulfur not being there, if the friction made that big of a difference in mileage the engine would practically eat itself alive...it is the process in which sulfur is removed that effects fuel economy. The current distillation methods used to remove the sulfur from diesel fuel also causes a massive drop in energy content over previous types of diesel. :smart:
  • Owner

But it still come back to the simple problem of the current fuel is ~520 HFRR roughly and Bosch suggest that we use <450 HFRR fuels to keep the fuel system happy. Bad part is very few additive actually make the grade... Because when you take a sample of any of the fuel additives today and leave them out most of them evaporate in a few days leaving a residue of some sort that is sticky/tacky. Remember a true lubricant doesn't evaporate!

so 128to1equals 1 oz. to 1 gallon..correct?that is what you do mike??so is that plenty..border line..a little more than what we should be using?i am sure some folks would like a simple mixture table.cuz your that :smart:...thank you:thumbup2:

Correct 1oz to 1 gal. = 128:1. Easy math.Use the same number of gallons pumped for number of ounces. What you are looking for is a HFRR below 450, this is per the Bosch study. The calculations that I did indicate that the HFRR with 2 stroke is about 383, with 128:1. This translates to very easy math. To get to 450HFRR, you can use 175:1 which uses lots of math. From what I understand, anything below 100:1 is not helping the engine any, and it may be harmful. Just remember that this is in theory.

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