need help with overheating .16

[parris001]

Maybe instead of saying there was more compression with a higher nitro content I should have said there was higher compression pressures. If you could run a nitro engine with a compression gauge installed you'd see a higher pressure reading as nitro levels increase.

Here's a scenerio for you rocknbil...... I work in the on highway diesel market, buses specifically. I can take a 500 hp engine running a max of 20 psi of boost and run anywhere in the country and it never overheat. Take that same engine and do nothing but raise the max boost to 30 psi (okay, the computer will compensate and add more fuel) and the power will probably go up to about 550 hp and the likelyhood of overheating becomes a real issue. And this all happens because suddenly you're making more power and where your cooling system (ie. the heatsink) has the ability to only absorb a given quantity of heat, once that limit's been reached you're going to begin running hot or at the least hotter.

Power = heat. Harness the power or loose it as heat

AC48, it sounds like you have crap for fuel if you're getting that much liquid in the exhaust. Bum a tank of known good stuff from a buddy and see what happens

 

[rocknbil]

Like I said, I don't know if I agree with the more nitro=cooler temps, but that's everyone's claim.

 

[AC48]

AC48, it sounds like you have crap for fuel if you're getting that much liquid in the exhaust. Bum a tank of known good stuff from a buddy and see what happens

Just to clear this up, this should be directed towards aj200415 and I agree with the soulution. BUy some better fuel and play with that.

Actually I'm pretty sure it just means there is a higher ratio of fuel to air. Because of nitromethane's oxidizing qualities, it allows more oxygen molecules to be packed into the C.C., but the effective volume should remain the same. (??)

Well, if there is more oxygen molecules in the combustion chamber this will raise the presser. Like you said the fuel to air ratio will increase which means there is greatter amount of fuel compared to before the 30%. Since there is more fuel then there is less space for the oxygen to compress which means higher pressures??? I'm just trying to think this through, I'm not sure whether I agree with the more nitro=less heat or not yet either.

 

[parris001]

I say let's all agree that I'm right (and :trashed: drunk). More nitro = more power (which) = more heat. The only exception I see to this..... is this.... Let's say before I was only able to run :moped: 50 mph on 15% nitro and now I'm running 20% and I'm running 60 mph (this is totally hypothetical so these numbers are just what I pulled out of my ass :horsecrap , and don't forget, I'm wasted). Is the extra 10 mph going to give me extra air flow across the head and additional cooling power that will more than make up for the increase in nitro content? Think about that rockinbil and let me know your thoughts.... (it's bad to be this trashed on a tuesday night)

I might have used more "smilies" than I was supposed to (hey, shoot :stickup: me). I'll not use any in my next post

 

[FastEddy]

I say let's all agree that I'm right (and :trashed: drunk). More nitro = more power (which) = more heat.

You are absolutely and totally wrong!!!!!

If you have an engine properly tuned on 20% then run 30% the next tank full without making any adjustments the temps of the engine will DROP..... This is a fact not a guess.

It is easier to get your engine to over heat with higher nitro content. The higher the content the smaller the tuning window gets.

Please don't argue your point of view if you are wrong. First off it makes you look stupid and secondly we don't like to promote bad information here.

-Ed

 

[parris001]

Oh well, now I'm gonna have to see proof of that there ol' FastEddy. In just the last week I helped a guy set up a RS4 Evo with a .15 HPI engine. He got the thing off of eBay and the tune-up was totally whacked so we tweaked and tuned and got it running good on 20% Blue Thunder. He bummed the tankful of Blue Thunder from another co-worker of ours and later that afternoon stopped at our LHS and accidently bought a quart of 30%, he intended to buy 20%. The next day (55 degrees outside) we were playing around and this guy was running his car and it began to stall and showed all the signs of overheating. We started looking at things and trying to figure it out and there it was...... 30% nitro. We bummed another tankful of the 20% and all was well again.

FastEddy, I don't mean to start anything with you, but you're talking to someone whom I bet has many more hours wrenching over engines than I'm willing to bet you have. I've built everything from a .049 Cox to a 16 cylinder 2384 CID diesel and I've had my hands inside an engine every day for the last 20 years. I've built stock engines to precise OEM specs and build modified engines depending on what the customer wanted. I've been running nitro R/C since '87 and have had numerous, numerous nitro powered toys. I'm all for healthy debate and I enjoy it. If I can get a discussion going and keep it alive for a while I find that to be a lot of fun. It makes us all think and that's good. For you to come on here and be so arrogant as to make a reply like you just did is stupid. Who the f%#* are you? The end-all authority? I may have been being a little silly and immature earlier but you my friend went a little too far. This is a message board. Thoughtful exchange should be welcomed here. I have research to back up my findings as you too probably do and we should be allowed to discuss them and in the end if we draw different conclusions then we can agree to disagree.

 

[FastEddy]

First off you can have as may hours as you like behind a wrench and still be wrong.
Your understanding of this subject is flawed. I will not try to educate you on this issue due to the fact your experience far out weighs any other member here on this forum. We should just listen to what you tell us and keep our mouth shut. Maybe, just maybe if at sometime during the last 20 years you have had your hands inside an engine you took some time to read and more importantly open your mind a bit to look and understand what others are trying to explain to you, you would get an even better understanding of a subject you believe you have mastered.

Its totally obvious that you are the master of anything you put your mind to and are more then willing to try and shove your mislead opinions down our pie holes. This forum has seen people like you come and go.

I will back off and consider myself schooled by the master.

You are right and everyone else is wrong.


NitroRC.com
Often engine temperatures are actually improved (lower) with higher nitro-methane contents because a richer setting can be achieved without adversely affecting throttle response. This is an important consideration when deciding on your blend of fuel.

Plus the 30% nitro keeps the engine cooler

I've been using 30% for about a year now.
Plenty of power at cooler operating temps.

With 30% you will get more power and LOWER temps.

I would like to make one correction, though. Higher nitro percentages actually tend to run cooler than the lower percentages.

higher the nitro % the cooler you would run.

Actually with 30% you can run leaner and get the same power. It has more nitro content. Thus it tends to run cooler at the same needle settings for 20% nitro..

After re-tuning it with the 30% I was able to get even better performance and lowered temp to 260-270

If you up the nitro % to 30% you can run richer and still get the power you want while running cooler.

Mine have always ran cooler with higher % as well.

It will actually run cooler on 30% but will be a little more difficult to tune.

The higher nitro content will allow you to run a little richer but keep the same performance.

You can use a 30% fuel if you would like. If your tuning skills are good a 30% will make it run cooler. 30% fuel is usually a race formula and is much less forgiving.
-Ed

the more nitro the cooler it runs 20% wil run a little hottrer than 30% with the same amount of oil. But you also sacrafice engine life with higher nitro content.

One thing to keep in mind is the higher the nitro content the cooler the engine will run.

Yes, the higher the nitro content the lower the temps as a general rule. The downside of this is the higher the nitro the quicker your engine will wear out

 

[StaticSag]

Wow, did i miss out on this one....LOL

If you go back to what I posted earlier I was talking oil content. From what I was " told" higher oil content will cause more heat. Someone didnt believe this. Let me clear that one up. I wanted someone to dispute that with some proof to back it up not because I think I'm right but because I dont have a clue.

Now then,

Does higher oil content cause more heat? i think I get the part that higher nitro content doesn't....LOL


Saggy

 

[husky24tn]

o.k i have a dumb question....

i understand more nitro = cooler temps....

but in 30% fuel isn't there less oil content?...that would cause less heat right?

just a guess....don't shoot me.....

 

[FastEddy]

I'm not sure if there is a correct answer.
Oil % is just a relative number. Each fuel company uses different lubrication delivery packages in the manufacturing process. Some are more efficient then others. There are companies that use Castor Oil and some that use synthetic blends. They guard the formulas and treat them as top secret.

A fuel that uses a higher % may have a less efficient blend then a fuel that uses a lower %. I haven't seen a company that has the same exact fuel with different oil content %. There very well may be one out there but I haven seen or even looked for it. If there is let me know and I would love to do some experimenting. There is always something to learn.

In general, higher nitro content fuel may contain the same or less oil %.
30%s are usually branded Race Fuel or Race Blends. Its all about the blend of nitro, oil, and other garbage they put into their mix.

What I can tell you is its all about the users tuning abilities. I know for a fact that this has more to do with temps then the fuel being used. I don't care what % of anything that is in the fuel whats on the other end of the screwdriver is more important.

Sorry I can't offer proof or find an answer for this one in either directions. However I've been told that others here have way more wrenching time then I do. What the hell do I know I'm just a noob to all this.

 

[rocknbil]

but in 30% fuel isn't there less oil content?...

Generally the oil content remains the same, it's the proportion of methanol that decreases.

edit: oops. Sorry F.E., simul-post.

 

[FastEddy]

Generally ~~it's the proportion of methanol that decreases.

This is true.

 

[HumboldtBlazer]

There's an absolute "sweet spot" that you get only by having both needles set right.

Yeah yeah yeah, and woman have been saying for years there's actually a "G" spot too. BS, I just don't buy it!
:smoke:

 

[FastEddy]

Yeah yeah yeah, and woman have been saying for years there's actually a "G" spot too. BS, I just don't buy it!
:smoke:

Try a bigger screwdriver you may change your mind.

 

[HumboldtBlazer]

poop, the truth hurts!

 

[FastEddy]

poop, the truth hurts!

I does doesn't it!
I was just guessing, I'm in the same boat as you. Its a myth.

WOODIE!!!!!!
We need some help here.

 

[aj200415]

killer thoughts guys! thanx for the help and keep em coming. I really need to no if i should stick to top fuel 10% and figure out y my engines runnin hot or get a gallon of 20. I heard from many people here in Ohio say that 20% will cool me down. I have a half gallon of 10% and i want to just use it up then go to 20% so i dont no what to do for shere.

 

[parris001]

Oh wow Fast Eddy, you sounded really pissed in your reply to my last post. Must be your time of the month. And you refered to me as a "master". And how could you have known that I am an ASE Master Certified Technician? You must be physic as well. I'm not here to shove my opinions down anyone's "pie hole". And I hope I'm very open minded because I spent around 100 hours last year being schooled on the latest trends and updates. And all the postings you listed proporting lower temps associated with higher nitro content was convincing as well. But I can give you a list of people that claim that John Kerry won the last election and will be our next president, but that don't make it true.

Look, here's all I want. Proof and an explaination of how it works. I've never seen an engine run cooler on more nitro than it does on a lower amount. I'm not saying it's not possible. I have dealt mostly with stock, entry level engines with small heatsinks and a low tolerance for nitro. Maybe some of these $300 engines thrive on the hard stuff and prefer it to the weaker stuff. I just want an explaination and some theory that goes a little deeper in depth to how this is possible, an explaination other than "FastEddy and a bunch of other people say it's so". You know, everybody used to think the Earth was flat, too. And that the Sun revolved around us.

You should learn not to take offense, FastEddy, when someone has a differing view than yours. Hey, open your mind to a view that's totally opposed to what you think or maybe even know to be fact.

Now back to the topic: If oil content goes down as nitro content goes up (this is someone else's assertion and not mine) then is it possible that the accelerated engine wear associated with running a high nitro content fuel is a result of lack of lube? I've got a friend with a 4Trac that's running 20% Wildcat fuel with 18% oil content (99% of that is synthetic) that's intended for planes and helicopters and he swears by the stuff. Good power and lots of lube. And at $16.99 a gallon it's cheaper than a lot of the fuel that's marketed as car fuel. I used Byron's airplane fuel at 20% in my cars until my LHS quit carrying it and had good luck with it.

 

[HumboldtBlazer]

Paris, not a good idea to be baiting a mod with such comments about Ed's monthly visitor. The rest of your post was fine, state your opinion and move on. And higher nitro does make your engine run cooler. I do not run 30% for the simple fact 20% is fast enough. If I did run 30% I would worry because I could damage my engine because 30% would make my engine run cooler. Cooler doesn't always equal no damage. Why you are asking? Well because the engine is running cooler doesn't mean there is enough oil to lubricate the piston sleeve. This can mislead people who tune by temp as the engine is showing a seemingly reasonable temp do to the nitro cooling the engine but there is not enough fuel with oil lubricating correctly. Let me give you a graphic but real world example. If you have ever had sex outside in the cold and she was dry, just because it was cold out doesn't mean you do not get road rash, get it? What happens when you spill nitro on your hand? What sensation do you feel at first?

 

[AC48]

Let me give you a graphic but real world example. If you have ever had sex outside in the cold and she was dry, just because it was cold out doesn't mean you do not get road rash, get it? What happens when you spill nitro on your hand? What sensation do you feel at first?

I like these examples, very creative with the first one lol.