JustinGB

I currently own a 4909 T-Maxx and the 3.3 Jato. I have been using byrons 15% fuel in both of them. I am fairly new to rc cars and haven't had these two for a long time. My friend told me that the byrons fuel i use, which come from my lhs, has too little oil content.

Upon research, I found out that the byrons have a 12% oil content, while Traxxas recommends their fuel, Top Fuel, I cannot find ANY concrete numbers to support that they have extra oil in their fuels except their product descriptions say so. Now, am I okay to keep running Byrons as I'm going to try a 30% nitro mix without adding oil? is 12% enough? Does anyone know how much oil content Top Fuel have?

Thanks,
Justin

rcdudegermy10

Really anything above 10% is good... use 12-15% of oil in combination with after run oil, that's the best... If you're just bashing you're gonna want a higher oil content and you're gonna want to use 20% nitro, this way your engine will last longer

JustinGB

Thanks a lot for the info. Just wanted to make sure, and i'll take that advice for that 20% as I only use it for recreational purposes. Thanks a lot!

rcnitrohead

Most of the crap spread around here is untrue about oil content, an excellent source for fuel content here:

Why 8% to 12% Oil

Using high oil content fuels (above 15%) in gas car engines won't provide improved engine life, as some would expect. Through extensive testing we've discovered the point of diminishing return as far as oil content to engine life is actually around 8% for most car engines. In other words any more oil than 8% in the fuel does noting to improve the life of a car engine. In fact the secondary effects of high oil content fuels can actually cause engine damage by encouraging over lean runs. Here's how.

Using high oil content fuel causes a car engine to be unresponsive during acceleration acting as if the engine were running rich. Typically when using high oil content fuel, in order to get crisp acceleration and response, an engine will need to be adjusted overly lean. In addition the high oil content prevents lean bog when an engine is over-leaned thus allowing the engine to run at this lean setting without the customary telltale lean bog warning letting you know the engine is overheating.

In summary, high oil content fuels don't give added protection. The point of diminishing return from a protection standpoint in a gas car application is about 8% oil depending on the oil type and engine. Anymore oil than this doesn't offer added protection and has potential secondary effects that reduce performance and can actually cause you to over lean your engine in an attempt to get crisp throttle response and acceleration. Do yourself a favor and follow these two rules:

Rule #1- Always use a high quality fresh fuel designed specifically for gas car use that has between 8% and 12% oil preferably with at least some castor in it. (We recommend Blue Thunder Sport or Race Formula)

Rule #2 - Don't use airplane fuels or any other type of fuels that have over 15% oil in your gas car engine.


This pretty much sums it up; from my personal experience, higher oil content lowers performance and this is especially noticeable in Traxxas Fuel which is trash. Byron's and O'Donnell's are two of the leading fuel blenders. It is safe to run any nitro percent in your engine unless it is specifically tuned for a certain percent in which you need to play with head shims, however running a different percent in a stock RTR engine like the one you have will have no negative effects. Engines running on higher nitro percents typically run cooler from what I've heard, I've always stuck to 20% for the last 5 years and just bumped up to 25% during the fuel shortage in the summer, barely any difference...

Tom.

Tom.

rcdudegermy10

Why would oil content make a difference? Isnt it the temperature of the engine that causes the oil to break down, thus creating over lean tuning, hot temperatures etc?

While it may be safe to use "any nitro content" does it make sense to? 30% are what professionals use, they rebuild their engine after every run if they arent getting a new one for free. 30% may make your car run cooler and faster but common rc knowledge proves that 30% makes your engine last shorter than running on 20%. There may be barely a difference, but to me any difference is a difference, and in this case a positive one...

rotor head33

^^^^^ i agree!!!

matts6887

Well, actually I feel that ur so called "friend' is wrong about byrons; as I along with countless other people have used byrons fuel before and have generally had very good luck with it; in fact Imo I think its some of the better stuff out there on the market. As for whether or not u are ok to run the byrons fuel; I would say yes u are ok to run it, however u might want to add just a very very small amount of castor oil to it and mix it in there to help to get the over all "content" closer to 20%(15%nitro, 5% oil or something similar to that I think, someone correct me on that if I am wrong) but overall u do want a bit higher content so u know the engine is getting proper lubrication, etc.

JLRevo

Forget the brands. 12% good for racing. 16% above good for bashing and not worriying about aro. I wouldnt nomal state this but many of my " lazy, cheap friends use high oil fuel and dont practice any after run procedures and they dont have problems. I dont do this at all. Just stating facts. But I would run 20% minimium nitro in any of my vehicles. Personaly : the more nitro the easier to tune. Just more wear. But by the time you notice the wear you'll have a new motor by then.

matts6887

I agree with running 20% nitro minimum. because while running 30% will indeed give ya more power; ur engine wont last as long overall running 30%......

Sugafree

The Oil Content Makes a Big Difference as the More Oil the More Heat.....The Higher the Nitro Content the Cooler it Runs.......

And I've been Running 30% Nitro with 8% Oil for Years.......I've Gotten over 10 to 12 Gallons on Every Engine I've had...... Most of them being Cheap Machs

It's People's Crappy Tuning Skills that Kill Engines Not Nitro Content......

rcdudegermy10

Then I need you to tune my engines

Obviously there's a reasonable amount of oil to run, kasarn sums it up simply

matts6887

+1!!! I would have to agree with the true fact that one of the major contributions to "killing" a engine/leading it to a early death, is by running it too lean....