Why not higher % nitro?
01-11-2013, 01:27 PM
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Why not higher % nitro?
If we can go from 20% nitro to 30% nitro and see 2-3mph gain and a few more rpm's, why not shim and go higher?
Why not add .13mm shim and go to 40% or even 50% nitro? Have we already determined that there will be no gain beyond 30%?
Sorry if we have already talked about this, I missed it.
Why not add .13mm shim and go to 40% or even 50% nitro? Have we already determined that there will be no gain beyond 30%?
Sorry if we have already talked about this, I missed it.
01-11-2013, 01:44 PM
#2
RE: Why not higher % nitro?
ORIGINAL: Ttowntoolman
If we can go from 20% nitro to 30% nitro and see 2-3mph gain and a few more rpm's, why not shim and go higher?
Why not add .13mm shim and go to 40% or even 50% nitro? Have we already determined that there will be no gain beyond 30%?
Sorry if we have already talked about this, I missed it.
If we can go from 20% nitro to 30% nitro and see 2-3mph gain and a few more rpm's, why not shim and go higher?
Why not add .13mm shim and go to 40% or even 50% nitro? Have we already determined that there will be no gain beyond 30%?
Sorry if we have already talked about this, I missed it.
01-11-2013, 01:52 PM
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RE: Why not higher % nitro?
Being that every hobby store you walk into has 30% or less for land based models, one would assume there is nothing beyond this threshold.....[&o]
01-11-2013, 02:00 PM
#4
RE: Why not higher % nitro?
ORIGINAL: Ttowntoolman
Being that every hobby store you walk into has 30% or less for land based models, one would assume there is nothing beyond this threshold.....[&o]
Being that every hobby store you walk into has 30% or less for land based models, one would assume there is nothing beyond this threshold.....[&o]
01-11-2013, 02:27 PM
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RE: Why not higher % nitro?
People at high elevations (think Denver, Colorado) have been known to use 40%. There has also been talk of some Pro's using 40 - 45% to gain an advantage. I believe the RB engine people
tested a 45% fuel at the 2010 World's. Results are mostly kept secret.
tested a 45% fuel at the 2010 World's. Results are mostly kept secret.
01-11-2013, 07:50 PM
#6
RE: Why not higher % nitro?
Up until recently the 1/8 On Road class used 40% Nitro...
I never got into it all that heavy, but I learned a few things while talking with the Calandras over at CRC Raceway...they are doing mostly electric stuff now I guess...it's been a while since I've been over there...
I haven't really kept up lately with all the rules, etc. etc. but they have switched, or are in the process of switching to 16% Nitro...(r c t e c h dot n e t has a lot more detailed info if you don't already know about that place? )
Expense, and parts longevity are good reasons to avoid high Nitro content...but if you want to give it a try, there's nothing wrong w/ doing your own experimenting.
Back in the 1970's, 80's and into the 90's the Formula 1 Pylon airplane engines (6.5 cc or .40 cu. in. ) were run on 60 to 70% Nitro...and if you got off lean, you would fry the piston / sleeve. Also, the plug would only last 1 flight... 3 OZ. per minute consumption rate...and so on...
I never got into it all that heavy, but I learned a few things while talking with the Calandras over at CRC Raceway...they are doing mostly electric stuff now I guess...it's been a while since I've been over there...
I haven't really kept up lately with all the rules, etc. etc. but they have switched, or are in the process of switching to 16% Nitro...(r c t e c h dot n e t has a lot more detailed info if you don't already know about that place? )
Expense, and parts longevity are good reasons to avoid high Nitro content...but if you want to give it a try, there's nothing wrong w/ doing your own experimenting.
Back in the 1970's, 80's and into the 90's the Formula 1 Pylon airplane engines (6.5 cc or .40 cu. in. ) were run on 60 to 70% Nitro...and if you got off lean, you would fry the piston / sleeve. Also, the plug would only last 1 flight... 3 OZ. per minute consumption rate...and so on...
01-12-2013, 06:10 AM
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RE: Why not higher % nitro?
Tower has in stock 50% car/truck fuel LM1943 so I know I can get it. I race 4 minute heat races dirt oval, I think there is room in the rules to allow this in our outlaw class. I was mostly wondering if I am competing against guys running higher nitro content than I.
01-12-2013, 08:32 AM
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RE: Why not higher % nitro?
ORIGINAL: proptop
I guess it depends on how ''Outlaw'' the Outlaw class is? Just the word ''rules'' in an Outlaw class is sort of contradictory...ain't it..? JMO
If you suspect some other guys are using 50%...they probably are...
I guess it depends on how ''Outlaw'' the Outlaw class is? Just the word ''rules'' in an Outlaw class is sort of contradictory...ain't it..? JMO
If you suspect some other guys are using 50%...they probably are...
01-13-2013, 02:30 AM
#10
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RE: Why not higher % nitro?
I run alot of 60% nitro in my speedboat which is equipped with a Sirio .27 Race engine (yes a normal aircooled buggy engine) It runs great (WOT for the most part) and don`t burn plugs. I have also tried the same fuel in different cars, but do not notice any difference in power to my normal 30%, other than having to readjust the carb some.
There`s alot of myths around high nitro, burning plugs every tankfull, destroying engines and so on, but that is not my experience anyways. My YS engines love it, but consumtion is high
There`s alot of myths around high nitro, burning plugs every tankfull, destroying engines and so on, but that is not my experience anyways. My YS engines love it, but consumtion is high
01-13-2013, 03:57 AM
#11
RE: Why not higher % nitro?
ORIGINAL: asmund
I run alot of 60% nitro in my speedboat which is equipped with a Sirio .27 Race engine (yes a normal aircooled buggy engine) It runs great (WOT for the most part) and don`t burn plugs. I have also tried the same fuel in different cars, but do not notice any difference in power to my normal 30%, other than having to readjust the carb some.
There`s alot of myths around high nitro, burning plugs every tankfull, destroying engines and so on, but that is not my experience anyways. My YS engines love it, but consumtion is high
I run alot of 60% nitro in my speedboat which is equipped with a Sirio .27 Race engine (yes a normal aircooled buggy engine) It runs great (WOT for the most part) and don`t burn plugs. I have also tried the same fuel in different cars, but do not notice any difference in power to my normal 30%, other than having to readjust the carb some.
There`s alot of myths around high nitro, burning plugs every tankfull, destroying engines and so on, but that is not my experience anyways. My YS engines love it, but consumtion is high
Oh... And throwing YS in there? Aren't they royal toads on anything less than 20%? For what the engine costs and what the fuel costs... Ouch. [:@]
01-15-2013, 12:19 PM
#12
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RE: Why not higher % nitro?
The YS engines still produce more than "normal" power on just 15% too, which is what I usually feed them. But for the extra WOW factor 60% is nice
02-11-2013, 11:20 PM
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RE: Why not higher % nitro?
You can also play with glow plugs for high rpm use, a lot has to do with humidity, if you run a high compression turbo head button and glow plug and live in a low humidity are. You may or may not have to shim the head with 30%, If it's running hot then shim it down. If it wont pull at high rpm get a hotter plug. once you get it set up right with 30% or even 60% nitro then it will only run good with that percentage of fuel. Running 60% nitro will shorten the life of the engine considerably, lack of oil in the fuel. If I'm gonna run 60% it would be on a well worn engine that has ware clearances between the bearing and can get a way with less oil and live. You'll need to lower compression about .003 thousands of a inch and keep a close eye on temp. If it runs hot then add another .01.5 thou shim should cool it down to run without risk of blowing the engine. I do hope this helps out, it works for me so I pass it on to you guys.
All the best Arless
All the best Arless
02-12-2013, 10:09 AM
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RE: Why not higher % nitro?
ORIGINAL: arless
You can also play with glow plugs for high rpm use, a lot has to do with humidity, if you run a high compression turbo head button and glow plug and live in a low humidity are. You may or may not have to shim the head with 30%, If it's running hot then shim it down. If it wont pull at high rpm get a hotter plug. once you get it set up right with 30% or even 60% nitro then it will only run good with that percentage of fuel. Running 60% nitro will shorten the life of the engine considerably, lack of oil in the fuel. If I'm gonna run 60% it would be on a well worn engine that has ware clearances between the bearing and can get a way with less oil and live. You'll need to lower compression about .003 thousands of a inch and keep a close eye on temp. If it runs hot then add another .01.5 thou shim should cool it down to run without risk of blowing the engine. I do hope this helps out, it works for me so I pass it on to you guys.
All the best Arless
You can also play with glow plugs for high rpm use, a lot has to do with humidity, if you run a high compression turbo head button and glow plug and live in a low humidity are. You may or may not have to shim the head with 30%, If it's running hot then shim it down. If it wont pull at high rpm get a hotter plug. once you get it set up right with 30% or even 60% nitro then it will only run good with that percentage of fuel. Running 60% nitro will shorten the life of the engine considerably, lack of oil in the fuel. If I'm gonna run 60% it would be on a well worn engine that has ware clearances between the bearing and can get a way with less oil and live. You'll need to lower compression about .003 thousands of a inch and keep a close eye on temp. If it runs hot then add another .01.5 thou shim should cool it down to run without risk of blowing the engine. I do hope this helps out, it works for me so I pass it on to you guys.
All the best Arless
In a worn engine it would be preferable to use a thicker oil..or if grade is not selectable then more of the oil.....using less oil than a worn engine has seen before (and running high rpm) will be a short road to the end.
02-13-2013, 06:11 AM
#15
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RE: Why not higher % nitro?
Tell you guys what, on race engines that are actually on tune you see a massive increase in power going up in Nitro %............going from 30%-40% makes a massive difference, and going from 30% to 70% would be an astronomical difference........... The only way the high nitro wont make more power is if your unable to tune the engine properly..... a poorly tuned engine will probably make no more power on 30% as the same poorly tuned engine will make on 50% .........however on a properly tuned engine going up in nitro % makes a gigantic difference.........In offroad racing many of the Pro's will run upwards of 50% nitro for the extra power............ You actually can visibly and audibly tell the difference between 30% and 40%, and you can most certainly tell the difference between 30% and 50%.................. If your engines aren't responding to higher nitro its likely that you are not tuning your engines correctly, as higher nitro makes more HP if it is burning correctly, its simple physics..... Put 50% nitro in one of my modifieds and watch how crazy things get ! More of you guys need to try racing out, I feel you would learn an amazing amount about running nitro and what they are capable of, as well as what a properly tuned nitro engine should sound like.......
02-13-2013, 09:52 AM
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RE: Why not higher % nitro?
ORIGINAL: supertib
Tell you guys what, on race engines that are actually on tune you see a massive increase in power going up in Nitro %............going from 30%-40% makes a massive difference, and going from 30% to 70% would be an astronomical difference........... The only way the high nitro wont make more power is if your unable to tune the engine properly..... a poorly tuned engine will probably make no more power on 30% as the same poorly tuned engine will make on 50% .........however on a properly tuned engine going up in nitro % makes a gigantic difference.........In offroad racing many of the Pro's will run upwards of 50% nitro for the extra power............ You actually can visibly and audibly tell the difference between 30% and 40%, and you can most certainly tell the difference between 30% and 50%.................. If your engines aren't responding to higher nitro its likely that you are not tuning your engines correctly, as higher nitro makes more HP if it is burning correctly, its simple physics..... Put 50% nitro in one of my modifieds and watch how crazy things get ! More of you guys need to try racing out, I feel you would learn an amazing amount about running nitro and what they are capable of, as well as what a properly tuned nitro engine should sound like.......
Tell you guys what, on race engines that are actually on tune you see a massive increase in power going up in Nitro %............going from 30%-40% makes a massive difference, and going from 30% to 70% would be an astronomical difference........... The only way the high nitro wont make more power is if your unable to tune the engine properly..... a poorly tuned engine will probably make no more power on 30% as the same poorly tuned engine will make on 50% .........however on a properly tuned engine going up in nitro % makes a gigantic difference.........In offroad racing many of the Pro's will run upwards of 50% nitro for the extra power............ You actually can visibly and audibly tell the difference between 30% and 40%, and you can most certainly tell the difference between 30% and 50%.................. If your engines aren't responding to higher nitro its likely that you are not tuning your engines correctly, as higher nitro makes more HP if it is burning correctly, its simple physics..... Put 50% nitro in one of my modifieds and watch how crazy things get ! More of you guys need to try racing out, I feel you would learn an amazing amount about running nitro and what they are capable of, as well as what a properly tuned nitro engine should sound like.......
02-14-2013, 09:33 AM
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RE: Why not higher % nitro?
ORIGINAL: Ttowntoolman
Next time I will just send a PM............Just thought this would be good public knowledge.
Next time I will just send a PM............Just thought this would be good public knowledge.
02-14-2013, 11:03 AM
#18
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RE: Why not higher % nitro?
ORIGINAL: Ttowntoolman
Being that my last modified engine came from YOUR shop, I trust the information you have provided. Too bad I had to wait a month for you to respond, I was thinking you did not know. Next time I will just send a PM............Just thought this would be good public knowledge.
ORIGINAL: supertib
Tell you guys what, on race engines that are actually on tune you see a massive increase in power going up in Nitro %............going from 30%-40% makes a massive difference, and going from 30% to 70% would be an astronomical difference........... The only way the high nitro wont make more power is if your unable to tune the engine properly..... a poorly tuned engine will probably make no more power on 30% as the same poorly tuned engine will make on 50% .........however on a properly tuned engine going up in nitro % makes a gigantic difference.........In offroad racing many of the Pro's will run upwards of 50% nitro for the extra power............ You actually can visibly and audibly tell the difference between 30% and 40%, and you can most certainly tell the difference between 30% and 50%.................. If your engines aren't responding to higher nitro its likely that you are not tuning your engines correctly, as higher nitro makes more HP if it is burning correctly, its simple physics..... Put 50% nitro in one of my modifieds and watch how crazy things get ! More of you guys need to try racing out, I feel you would learn an amazing amount about running nitro and what they are capable of, as well as what a properly tuned nitro engine should sound like.......
Tell you guys what, on race engines that are actually on tune you see a massive increase in power going up in Nitro %............going from 30%-40% makes a massive difference, and going from 30% to 70% would be an astronomical difference........... The only way the high nitro wont make more power is if your unable to tune the engine properly..... a poorly tuned engine will probably make no more power on 30% as the same poorly tuned engine will make on 50% .........however on a properly tuned engine going up in nitro % makes a gigantic difference.........In offroad racing many of the Pro's will run upwards of 50% nitro for the extra power............ You actually can visibly and audibly tell the difference between 30% and 40%, and you can most certainly tell the difference between 30% and 50%.................. If your engines aren't responding to higher nitro its likely that you are not tuning your engines correctly, as higher nitro makes more HP if it is burning correctly, its simple physics..... Put 50% nitro in one of my modifieds and watch how crazy things get ! More of you guys need to try racing out, I feel you would learn an amazing amount about running nitro and what they are capable of, as well as what a properly tuned nitro engine should sound like.......
If you want a answer from me your best to just email or phone me........I dont always read all the threads so I had no idea this thread was even here......And I most definitely did not realize this thread was intended for me to answer......
either way higher nitro makes more power if your burning it correctly....
02-18-2013, 02:27 AM
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RE: Why not higher % nitro?
I have an os 18tz modded running with 33% nitro. The engine has 2 shims right under the cooling head, I don't know the sizes but one is thinner than the other.
The qestion is if i should I add a third shim? Should I add a thin shim? Or should I use 3 thin shims?
Thanks guys
The qestion is if i should I add a third shim? Should I add a thin shim? Or should I use 3 thin shims?
Thanks guys
02-18-2013, 07:32 AM
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RE: Why not higher % nitro?
ORIGINAL: Car-Tune
I have an os 18tz modded running with 33% nitro. The engine has 2 shims right under the cooling head, I don't know the sizes but one is thinner than the other.
The qestion is if i should I add a third shim? Should I add a thin shim? Or should I use 3 thin shims?
Thanks guys
I have an os 18tz modded running with 33% nitro. The engine has 2 shims right under the cooling head, I don't know the sizes but one is thinner than the other.
The qestion is if i should I add a third shim? Should I add a thin shim? Or should I use 3 thin shims?
Thanks guys
02-18-2013, 09:55 AM
#21
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RE: Why not higher % nitro?
The correct head clearance to burn 20% to 30% nitro in a big block is equal to X. Does X change when you go up in percentage of nitro from say 30% to 50%? To me this is the question that still needs an answer.......Thanks for all the reply's so far!
02-18-2013, 10:56 AM
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RE: Why not higher % nitro?
ORIGINAL: Ttowntoolman
The correct head clearance to burn 20% to 30% nitro in a big block is equal to X. Does X change when you go up in percentage of nitro from say 30% to 50%? To me this is the question that still needs an answer.......Thanks for all the reply's so far!
The correct head clearance to burn 20% to 30% nitro in a big block is equal to X. Does X change when you go up in percentage of nitro from say 30% to 50%? To me this is the question that still needs an answer.......Thanks for all the reply's so far!
If nitro percentage isincreasedby a large amount without adding head shimming, detonation is likely to take place.
02-19-2013, 09:39 AM
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RE: Why not higher % nitro?
ORIGINAL: Ttowntoolman
The correct head clearance to burn 20% to 30% nitro in a big block is equal to X. Does X change when you go up in percentage of nitro from say 30% to 50%? To me this is the question that still needs an answer.......Thanks for all the reply's so far!
The correct head clearance to burn 20% to 30% nitro in a big block is equal to X. Does X change when you go up in percentage of nitro from say 30% to 50%? To me this is the question that still needs an answer.......Thanks for all the reply's so far!
Ideally the head clearance will always be the same and you adjust the volume in the head. As I do not imagine you will be making/modifying head buttons, then switching from 30-50% will require you to add shims (to increase the volume).
02-19-2013, 10:08 AM
#24
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RE: Why not higher % nitro?
ORIGINAL: Ttowntoolman
The correct head clearance to burn 20% to 30% nitro in a big block is equal to X. Does X change when you go up in percentage of nitro from say 30% to 50%? To me this is the question that still needs an answer.......Thanks for all the reply's so far!
The correct head clearance to burn 20% to 30% nitro in a big block is equal to X. Does X change when you go up in percentage of nitro from say 30% to 50%? To me this is the question that still needs an answer.......Thanks for all the reply's so far!
Not usually ! we run higher niro on the same shimming...High oil requires more shims then high nitro does.............. Usually the head has a sweet spot where it wants to be set and you can run 20% or 50% and it will run fine...glowplug temp is what we usually change..............Adding shims ends up defeating the gains made by going higher in nitro...this is providing you have he engine in the sweet spot............
02-19-2013, 10:43 AM
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RE: Why not higher % nitro?
ORIGINAL: supertib
Usually the head has a sweet spot where it wants to be set and you can run 20% or 50% and it will run fine...glowplug temp is what we usually change
Usually the head has a sweet spot where it wants to be set and you can run 20% or 50% and it will run fine...glowplug temp is what we usually change
Have you got any comparison graphs with high-low nitro..cold-hot plugs on the same engine?