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Mixing fuels.

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militarymaxx

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Littleton, NH
RC Driving Style
  1. Bashing
  2. Racing
I bought a quart bottle of 30% blue thunder race formula thinking it was 20%. Stupid me, lost the receipt and can't return it. Do I eat the 12$, give it away to someone who uses 30%, or can I mix it into a gallon of 20% ?
 
The LHS guy says if I want to start using a higher percentage fuel that I might need to add a shim in the head. But I am going to stick with 20%. I would love adding this quart of 30% it to a fresh gallon of 20%, but am a little concerned that I might do some damage to an engine that was broken in using 20% and has run on nothing but 20%.
 
Hmmm.... I can't see any problem with running the 30% in the .21 but check with the manufacturer.

Maybe there is someone else here who has run 30% in that mill without grief.
 
I know of people that run 30% BT race in that exact engine but once you switch you can't go back to 20%. You gain a little performance and sacrafice a little life. How's your tunning skills? I still do not feel comfortable with running 30% but I feel I am getting close.

even though you don't have the reciept the should swap it for you if you have not opened it.
 
If worse comes to worse, you can send it to me. Ill PM ya my address if you ask.:smoke:

Nah, But if your LHS wont accept it, you could find someone who wants 30 and sell it to them for like a dollar cheaper then go get the 20. Just make sure you read the Label next time!:ninja:
 
I'd be running 25% :D 20% is what I run in my .15 cv-rx and I run 25% in my B01. Get a quart of 20% and mix it and get 25%. you can do that or is you really wanny run 20% get a quart of 10% and mix the two. No lost money.
 
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Christian, it doesn't matter. You can move up or down percentages. You just need to give the engine a bit of a chance to adjust to the new fuel, but I'm sure you knew that. Oh, and you need to retune.
 
I thought 30% made for more bang if you will. Racers will move up 5-10% nitro content to extend the life of the engine. Maybe I was assuming that you can't go back because that leads me to believe it makes more combustion or more bang(forgive me if I am not using the right term.) So if you went back wouldn't the p/s fit be to lose and you would lose a lot of power? I have never done it so it's pure speculation on my part but it makes sense in my mind.
 
You can go back and forth at will with no issues.
I have used both in several engines without changing any shims as well. You will find the 30% will make your temps drop a bit as well.
 
I normally use 30% but the LHS had some sweet 40% that I ran yseterday and I loved it. The difference was like night and day, however when I had switched from 20% to 30% the tuning was a little more difficult. The higher % the less user friendly the HSN and LSN are to tune.
 
Is there alot of tuning to be done if you raise the nitro content? If so my little full throttle boost idea ain't goint to work.
 
No. Its not bad at all. Granted, you will want to drop a colder plug if you are running a hot. But no, not much tuning at all. First thing to watch is your idle IMO.
 
I found no need to change the plug when I move from 20%-30% or vice versa.
Just a minimal amount of tuning with the HSN.

Put the 30% in and run your engine for a few minutes. Take temperature readings often and watch for smoke and performance. Adjust your tuning as needed. Just as a safeguard you may want to richen the HSN ¼ turn to start.
 
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