Dasupacat1

iTrader: (25)

Less oil content, good or bad?
There are some at my local track that say less oil content makes your engine run cooler. I disagree because I think that more oil helps cool your engine while lubricating and will help extend engine life. If I'm wrong then thats cool. I just don't see how it would run cooler with less%. Can someone esplain this? I don't doubt that less oil will make the engine faster by making more power, but I'd rather have longer engine life then anything else. I run 12% where as they all swear by 10%.
What's your .02? Does less oil make your engine run cooler?

wingracer

iTrader: (24)

I run 8% in on road but I would not recommend lower then that.

If you are running 12% and switch to 8% you will have 4% more fuel in the tank and in theory get 4% more runtime.

Nitro syco

your motor will run faster with lesss oil, but if you run it to lean your motor will be more damaged than it would have been with a higher oil content. So basicialy you have a smaller tuning window. Just continue running what you are, you wont be able to notice hardly anything with 2% difference.

vladconnery

iTrader: (35)

I run the same 12% oil with byrons gen2. I like you are more interested in long engine life. If thats working for you and your still having success on the track stay with it. Why risk your $300 engine on a MAYBE.

British Menace

I run fuel with 18% all synthetic oil content! Also, it has 15% Nitro.
I want my engine to last a long time. It smokes like an SOB though...lol.

The only time I notice the lack of power is on a long straightaway. But that's ok........I'll get them on the jumps and corners....lol.

I've had some experience running such fuels before. My last motor I ran with similar oil and Nitro content lasted for 4 years !

If your not a serious racer who notices the difference or needs the extra 1/4 or 1/2 second faster lap times then I would go with as higher oil content as you can get. Try and get a fuel with good synthetic oils in though. And, depending on the amount of oil content and the Nitro content used. You may have to go with a lightly hotter plug and take out a shim or so.

Regards,
British Menace

itsshemp

iTrader: (9)

MY "opinion" on this is that oil lubrication qualities of todays oils, are MUCH better than those of yesteryear, and as a result, less oil is needed to get the same protection. Synth oils dont break down, like older versions. I believe that oil actually retains heat, so less oil would actually help cool. Of course you still want the lubrication protection.

I have been running the Gen2 9%, and it seems to leave a nice film of oil on the walls, even after running the engine all day. I still add afterun oil after.

Im sure there will be many opinions on this subject, but this is my personal opinion. I am no engineer, but maybe one will toss in there thoughts.

Coming from a dirt bike background, I made the switch years ago from Caster based oils to Synth oils, and was able to run a much leaner ratio, and still had great engine protection, and performance. There is a fine line though, since oil does help seal the piston to the walls..... Geez always something to have to consider.

largeorangefont

iTrader: (4)

Oil does not carry away heat, unburnt fuel carries away heat. Generally speaking, more oil will make the engine run a bit hotter. This is because the other fuel ingredients carry heat away more efficiently than oil. When you add oil, you are lowering the amount of these other ingredients.

In a 2 stroke engine, oil is for lubrication, and the fuel is coolant. Oil also does not burn like fuel does. The more oil in the fuel, the less fuel ends up in the combustion chamber which means less power.

The more oil, the more forgiving the engine will be to a poor tune. The less oil, the more responsive the engine will be, but the tune must be better or you will damage the engine. Addtionally, it is also easier to tune with less oil.

I have run as low as 4% oil content and you can really feel the the difference the engine runs more "crisp". We also found temps were sucessively cooler when properly tuned after back to back tests of 10%, 8%, 6% and 4% oil content.

superdave2

iTrader: (3)

im running i think like 20 or 14 percent im not exactly sure but i used to be running like 18 and found out my motrs last long enough so i went down you get more snap off the line which is what i think and it also runs a little better

Dasupacat1

iTrader: (25)

That does make sense. My thinking was that less lube would create more heat because of friction since there is less oil film.

superdave2

iTrader: (3)

yep and more lube will make it run cooler but it wont have as much snap out of you motor but if you run a lower content of oil you will get a more accelrating motor

seayya

iTrader: (2)

My experience: I have ran several different kinds of fuel with different oil contents. I have found that with the lower oil content I can run colder plugs, the motors are running cooler, more punch, and are by far more consistent (less tuning). I still have a good oily film inside the motors as well, and the motors are lasting awhile for me as well. I have a Picco with 9 gallons, a P5 with more than 10 gallons, and I could go on but you get the idea.

I was playing around last weekend with my NovaRossi 367 (no clue how much fuel has been through it) and I was trying to find the breaking point. Never found it. I was running my Cold Fusion fuel 30%/9% 80% synthetic/20% castor. I kept leaning it to see how hot it would go and still run. I was running in the parking lot of my local track doing wide open runs about 100 yards long, and did this about 10 to 15 times. Motor got up to 423 degrees still was running, good pinch, and no visible damage to the piston and sleeve. Motor still runs good.
I know this was a dumb thing to do, but I do not run this motor.

ezveedub

iTrader: (17)

I would stick to 12% oil content fuel. It seems to be the best balance for lube and power. More oil will help with longevity, but at a cost of power. Oil content affects the burn rate of fuel. Less oil content fuel burns quicker. As for lubricants of today versus a few years ago, not much has changed IMO. Actually, the original lube of castor oil has been very hard to match under severe heat protection where most synthetics burn off.

Allumina

iTrader: (27)

I didnt read all the wall of text posts so if someone alreayd said this sorry

Things you know:

The percentage of nitro in your fuel remains constant [regardless of oil content], lets use 30% for this example.

That leaves 70% left in the mixture, factor in oil, lets say 8% or 12% for the two options.

In a 12% oil mixture, that leaves you with 58% extra, and in an 8% blend, thats 62%.

The other 58 or 62% of this concoction is comprised of Methanol. Methanol is an extremely COOL burning fuel, therefore the more Alky [Methanol] you've got in your motor, the cooler it will run.

Example, I run nonwing sprintcars professionally, and our motors are 360 cubic inch, small block chevy's, naturally aspirated that produce over 800 horsepower running on pure methanol. Our motors hardly ever get over 215, even after a long main.

Hope that helps!

p.s. I would just stick to the 12%, better safe than sorry. My rule of thumb is, 8% is for drivers who have their motors sponsored

wes95_z28

iTrader: (3)

I can tell you from experience, that the switch from 12% to 10% isnt enough to even worry about in terms of performance, or temperature drop.

Yes my motors did come down in temp slightly 5-8 degrees while running the 10%, but the performance gain wasn't huge, actually on a dusty track it made it just that much more difficult.

But if longevitity is the more important thing to you ( as it is with me) stick with the 12%. I have made the switch back, and once you cross that fine line of 10% oil the tune does become pretty touchy, not so much with the 12%.

Just remember, a motor tuned correctly running 20% oil content, will always run better and live longer than any motor running any % of oil content that isnt tuned correctly.

superdave2

iTrader: (3)

i know in drag racing that the 100% alcohol burning motors dont even run a water pump to help cool the motor but they arnt running long enough to get the motor too hot to start to damage things