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Function f(x) = 9.61307 * 1.0959 ^ MPG

There is simpler chart that I have devised with rounded numbers to make it easier to remember. I explained it well in the link below which is essentially a guide and not something written in stone.

There are two keys to this guide. The first is the chart that respects the chance in oil demand at different rpm and load. The second is the simple method to calculate a percentage less or more oil using the mpq (Miles Per Quart of oil). So if you prefer 20% less oil, then it is a simple % calculation based on mpq which respects the need for oil at different rpm and load. I firmly believe this is a leap forward.

The hidden advantage is if a tech or the owner makes a change to the oil consumption either purposely or inadvertently, then this change becomes easy to calculate. The same holds if an engine is rebuilt or a change in track or clutching, or anything that affects the fuel consumption. As long as you know the Fuel vs Oil consumption before the change, then you have the ability to compare the before and after.

I keep thinking that I need to submit this to BRP. I know they have their own chart which is essentially what I was able to extract. But the ease in calculating the % increase or decrease may be something new.

Oil vs Fuel consumption (see post 284 that this links to)

**Calculating change in oil consumption**

Example A:

Example A:

Sled @ 11 mpg consumes too much oil @ 70 mpq for an average ratio of 25:1

Target decrease @ 85 mpq for a ratio of 31:1

Convert mpq to quarts per 100 miles

100 / 70 mpq = 1.429 quarts

100 / 85 mpq = 1.176 quarts

Calculate percentage

( (1.176 / 1.429) - 1) x -100 =

**17.7%**decrease in oil consumption

An increase from 70 mpq to 85 mpq =

**21%**increase in distance

( (85 mpq / 70 mpq) - 1) x 100 = 21.4%

**Example B:**

Sled @ 16 mpg consumes too little oil @ 225 mpq for a ratio of 56:1

Target increase @ 170 mpq for a ratio of 42:1

Convert mpq to quarts per 100 miles

100 / 225 mpq = 0.444 quarts

100 / 170 mpq = 0.588 quarts

Calculate percentage

( (0.444 / 0.588) - 1) x -100 =

**24.5%**increase in oil consumption

A decrease from 225 mpq to 170 mpq =

**32%**decrease in distance

( (225 mpq / 170 mpq) - 1) x 100 = 32.4%

**Simpler chart**

4 mpg @ 14:1 @ 14 mpq

5 mpg @ 15:1 @ 19 mpq

6 mpg @ 17:1 @ 25 mpq

7 mpg @ 18:1 @ 32 mpq

8 mpg @ 20:1 @ 40 mpq

9 mpg @ 22:1 @ 49 mpq

10 mpg @ 24:1 @ 60 mpq

11 mpg @ 26:1 @ 70 mpq

12 mpg @ 29:1 @ 85 mpq

13 mpg @ 32:1 @ 105 mpq

14 mpg @ 35:1 @ 120 mpq

15 mpg @ 38:1 @ 140 mpq

16 mpg @ 42:1 @ 170 mpq

17 mpg @ 46:1 @ 195 mpq

18 mpg @ 50:1 @ 225 mpq

19 mpg @ 55:1 @ 260 mpq

20 mpg @ 60:1 @ 300 mpq

**Example C:**

This is the latest chart I put together on Feb 21st, 2022 for a 2018 600 Carb.

The range starts with

**Longevity**for the engine with the oil consumption taken from the E-TEC. The

**Economy**provides roughly 20% greater distance for a quart of oil which figures about 17% savings.

The cool part is mixing 200:1 in the gas raises the oil consumption from

**Economy**to

**Longevity**with the benefit of running mix through the carbs and reeds. Who doesn't want a little more lube to help prevent the carb slides from wearing and causing a high idle? With a 100:1 mix, then the oil injection can be lowered even further for a total of 40% greater distance and still have the same oil consumption for

**Longevity.**

Note how the

**Economy**numbers are the same as

**Longevity**shifted up one line. It makes for an easy chart to remember and use.

The mpq and ratio numbers have been rounded for ease of use, There is no need for being ultra accurate, but rather in the ball park.

Range for

**Longevity**and

**Economy**

12 mpg @ 85 - 100 mpq (~28:1 to ~34:1)

13 mpg @ 100 - 120 mpq (~30:1 to ~37:1)

14 mpg @ 120 - 140 mpq (~34:1 to ~41:1)

15 mpg @ 140 - 170 mpq (~38:1 to ~45:1)

Economy +

**200:1 mix**= Longevity

Below are several topic links on the subject. Take note of at least the first and last one.

A debate on oil to gas mixture

Trailrider with the 800 SDI in Post #24

Trailrider with 6,600 miles over 212 running hours since last rebuild

Ratios from the Ski-Doo Race Manuals in Post #7

Will too much oil cause a lean failure?

Trailrider's example from a big wood processing timber operation