More Nitro Content?
09-28-2007, 10:34 AM
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More Nitro Content?
I was in my lhs a week or so back, picking up a gallon of nitro for my savage, the k4.6, and he was telling me, that i should 30% (i have always used 20%) he was saying it give a better idle, and easier tuning, is this true?
I have seen people run 20% in alot of big blocks, even .30's. but i thought if u go 30% u have to put a extra head shim on, and plug shim, to handle that much extra nitro, but u end up pretty much back at the power of 20%, so is it worth going to 30%, or just stick with 20%.
I have seen people run 20% in alot of big blocks, even .30's. but i thought if u go 30% u have to put a extra head shim on, and plug shim, to handle that much extra nitro, but u end up pretty much back at the power of 20%, so is it worth going to 30%, or just stick with 20%.
09-30-2007, 06:28 PM
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RE: More Nitro Content?
30% makes the car perform a lot better, and less sluggish, but kills engine life by a few tanks. for larger engines, u should probably stick with 20%
09-30-2007, 07:51 PM
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RE: More Nitro Content?
theoretically 30% nitro should make your engine run hotter, but being able to run rich and still maintain performance means you can run cooler with 30% then with 20% without loosing performance.
10-02-2007, 02:10 AM
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RE: More Nitro Content?
running more the 12% oil in 20% nitro, and 10% in 30% nitro doesn't effect engine life at all, running more just lowers performance without adding extra protection, and i don't see how having more energy involved is going to decrease engine life, if you running at the same temp with both fuels, with the same operator with a similar tune will give you similar engine life, has for me anyone.
10-02-2007, 05:43 PM
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RE: More Nitro Content?
It wont make your engine run cooler. The more nitro, the hotter it burns. So if you have already put 20% and run it dont switch to 30%, it will need to be rebroken in and if you dont see better performance, you cant swich back. More oil in 30% is better cuz ifits burning hotter it will make the castor in the fuel start to thin out and wont protect that well.
Hope this helps you guys
Hope this helps you guys
10-02-2007, 05:47 PM
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RE: More Nitro Content?
ORIGINAL: ttoks
running more the 12% oil in 20% nitro, and 10% in 30% nitro doesn't effect engine life at all, running more just lowers performance without adding extra protection, and i don't see how having more energy involved is going to decrease engine life, if you running at the same temp with both fuels, with the same operator with a similar tune will give you similar engine life, has for me anyone.
running more the 12% oil in 20% nitro, and 10% in 30% nitro doesn't effect engine life at all, running more just lowers performance without adding extra protection, and i don't see how having more energy involved is going to decrease engine life, if you running at the same temp with both fuels, with the same operator with a similar tune will give you similar engine life, has for me anyone.
Why do you think a 8000hp Top Fuel engine doesn't last as as long as a similar sized blown streetable 800hp V8 running on pump gas?
The comparison is exaggerated for sure and in reality the difference between 20 and 30% is barely noticeable BUT still there.
10-02-2007, 05:49 PM
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RE: More Nitro Content?
ORIGINAL: RC_HAVOC
It wont make your engine run cooler. The more nitro, the hotter it burns. So if you have already put 20% and run it dont switch to 30%, it will need to be rebroken in and if you dont see better performance, you cant swich back. More oil in 30% is better cuz ifits burning hotter it will make the castor in the fuel start to thin out and wont protect that well.
Hope this helps you guys
It wont make your engine run cooler. The more nitro, the hotter it burns. So if you have already put 20% and run it dont switch to 30%, it will need to be rebroken in and if you dont see better performance, you cant swich back. More oil in 30% is better cuz ifits burning hotter it will make the castor in the fuel start to thin out and wont protect that well.
Hope this helps you guys
An engine can't be broken in twice. Once it's done it's done. You just need to retune it for the new fuel.
10-02-2007, 06:06 PM
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RE: More Nitro Content?
ORIGINAL: RC_HAVOC
It wont make your engine run cooler. The more nitro, the hotter it burns. So if you have already put 20% and run it dont switch to 30%, it will need to be rebroken in and if you dont see better performance, you cant swich back. More oil in 30% is better cuz ifits burning hotter it will make the castor in the fuel start to thin out and wont protect that well.
Hope this helps you guys
It wont make your engine run cooler. The more nitro, the hotter it burns. So if you have already put 20% and run it dont switch to 30%, it will need to be rebroken in and if you dont see better performance, you cant swich back. More oil in 30% is better cuz ifits burning hotter it will make the castor in the fuel start to thin out and wont protect that well.
Hope this helps you guys
theres no such thing as "rebreak in". you can switch from 20 to 30 then back to 20, you just need to retune and reshim
10-02-2007, 08:06 PM
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RE: More Nitro Content?
LoL......ok not 'Re-breakin' but the piston WILL wear more from the heat of the 30%, get it?. Like what my dad did with our ford escort, he overheated it to the point that we had to swich to a hotter sparkplug so the piston would fit in the cylinder again. Ask any mechanic and he would know that you can either run the engine hotter or you can rebore it and have oversized pistons installed. I also had to to this with my ATC for the same reason(its really hard to keep any air-cooled engine from overheating at 115F where I live). See where im going with all this? If not lsurber could give you a good example, if hes willing to post. Ill give one more example, more nitro=more heat and if you have more heat then parts get bigger(pistons in normal cars get to about 700F and have more then 1mm of cylinder to piston clearance.
10-02-2007, 08:11 PM
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RE: More Nitro Content?
Sorry man. Wrong again.
It's not going to be hotter with 30%. If you temp your engine with 20% and 30% and see 240F both times the piston is not going to be hotter in the one you just ran 30% through.
It's just not possible. If it was in fact hotter you would see that with the temp gun, ie it would not temp at 240F.
ABC engines can not be compared with ringed car engines or any ringed engine for that matter.
edit again:
Piston cylinder clearance of 1mm... OK that might be but in the car the piston rings do all the work sealing, not the pistons.
It's not going to be hotter with 30%. If you temp your engine with 20% and 30% and see 240F both times the piston is not going to be hotter in the one you just ran 30% through.
It's just not possible. If it was in fact hotter you would see that with the temp gun, ie it would not temp at 240F.
ABC engines can not be compared with ringed car engines or any ringed engine for that matter.
edit again:
Piston cylinder clearance of 1mm... OK that might be but in the car the piston rings do all the work sealing, not the pistons.
10-02-2007, 08:28 PM
#18
RE: More Nitro Content?
lol, there is so much confusion here. Come to a consensus for python already
[8D] Ive always run 20%, but may switch sometime soon, its just a lot more popular at my lhs, i dont care about the 5% performance increase
[8D] Ive always run 20%, but may switch sometime soon, its just a lot more popular at my lhs, i dont care about the 5% performance increase
10-02-2007, 08:48 PM
#19
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RE: More Nitro Content?
i dont feel like reading the entire thing but here it goes
more nitro will not make it run hotter, in fact, it has the potential to run cooler, why? well when you add more nitro, your engine makes more power, this allows you to run a slightly richer setting (more oil flow) without any power loss, even though the flame may be a little hotter, it doesnt matter with proper oil, that why car combustion chambers can get to over 3000 degrees on the power stroke, even though the steel melts at around 1800-2000
more nitro doesnt have to make your engine wear out sooner, sure more nitro makes more pressure, with a proper tune, adequate oil, and not revving it under no load, the engine should very well last just as long as an engine on 20% fuel, dont you think if it wore out engines alot faster that it would be a well known fact by now, and noting the dragster engine comment, the 8000hp dragster engines dont last long because they are pushing the edge of engine technology, you have 1000hp per connecting rod....most cars have maybe 50hp per connecting rod...thats why they dont last as long, that and they are run at full throttle until they nearly blow
there is no re-breakin required, your engine is already broken in, what else are you going to do to it, its going to be under more pressure at some time or another, easing into the pressure wont do you a single thing, just retune and go, this is by no means a perfect example but when you switch from regular to premium in your car do you act like your engine is new and break it in again? i think not
i know im prolly gunna get crap from this but get over it
more nitro will not make it run hotter, in fact, it has the potential to run cooler, why? well when you add more nitro, your engine makes more power, this allows you to run a slightly richer setting (more oil flow) without any power loss, even though the flame may be a little hotter, it doesnt matter with proper oil, that why car combustion chambers can get to over 3000 degrees on the power stroke, even though the steel melts at around 1800-2000
more nitro doesnt have to make your engine wear out sooner, sure more nitro makes more pressure, with a proper tune, adequate oil, and not revving it under no load, the engine should very well last just as long as an engine on 20% fuel, dont you think if it wore out engines alot faster that it would be a well known fact by now, and noting the dragster engine comment, the 8000hp dragster engines dont last long because they are pushing the edge of engine technology, you have 1000hp per connecting rod....most cars have maybe 50hp per connecting rod...thats why they dont last as long, that and they are run at full throttle until they nearly blow
there is no re-breakin required, your engine is already broken in, what else are you going to do to it, its going to be under more pressure at some time or another, easing into the pressure wont do you a single thing, just retune and go, this is by no means a perfect example but when you switch from regular to premium in your car do you act like your engine is new and break it in again? i think not
i know im prolly gunna get crap from this but get over it
10-02-2007, 09:14 PM
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RE: More Nitro Content?
ORIGINAL: hpi apollo
i dont feel like reading the entire thing but here it goes
more nitro will not make it run hotter, in fact, it has the potential to run cooler, why? well when you add more nitro, your engine makes more power, this allows you to run a slightly richer setting (more oil flow) without any power loss, even though the flame may be a little hotter, it doesnt matter with proper oil, that why car combustion chambers can get to over 3000 degrees on the power stroke, even though the steel melts at around 1800-2000
more nitro doesnt have to make your engine wear out sooner, sure more nitro makes more pressure, with a proper tune, adequate oil, and not revving it under no load, the engine should very well last just as long as an engine on 20% fuel, dont you think if it wore out engines alot faster that it would be a well known fact by now, and noting the dragster engine comment, the 8000hp dragster engines dont last long because they are pushing the edge of engine technology, you have 1000hp per connecting rod....most cars have maybe 50hp per connecting rod...thats why they dont last as long, that and they are run at full throttle until they nearly blow
there is no re-breakin required, your engine is already broken in, what else are you going to do to it, its going to be under more pressure at some time or another, easing into the pressure wont do you a single thing, just retune and go, this is by no means a perfect example but when you switch from regular to premium in your car do you act like your engine is new and break it in again? i think not
i know im prolly gunna get crap from this but get over it
i dont feel like reading the entire thing but here it goes
more nitro will not make it run hotter, in fact, it has the potential to run cooler, why? well when you add more nitro, your engine makes more power, this allows you to run a slightly richer setting (more oil flow) without any power loss, even though the flame may be a little hotter, it doesnt matter with proper oil, that why car combustion chambers can get to over 3000 degrees on the power stroke, even though the steel melts at around 1800-2000
more nitro doesnt have to make your engine wear out sooner, sure more nitro makes more pressure, with a proper tune, adequate oil, and not revving it under no load, the engine should very well last just as long as an engine on 20% fuel, dont you think if it wore out engines alot faster that it would be a well known fact by now, and noting the dragster engine comment, the 8000hp dragster engines dont last long because they are pushing the edge of engine technology, you have 1000hp per connecting rod....most cars have maybe 50hp per connecting rod...thats why they dont last as long, that and they are run at full throttle until they nearly blow
there is no re-breakin required, your engine is already broken in, what else are you going to do to it, its going to be under more pressure at some time or another, easing into the pressure wont do you a single thing, just retune and go, this is by no means a perfect example but when you switch from regular to premium in your car do you act like your engine is new and break it in again? i think not
i know im prolly gunna get crap from this but get over it
no crap from me...id just like to add in addition to retuning you may need to reshim
10-02-2007, 11:44 PM
#21
RE: More Nitro Content?
OK...here's a few facts. Nitro (by itself) has to be run far richer than just methanol to get the correct air/fuel ratio so the more nitro you add to the methanol the richer the mixture has to be. This means you're dumping a lot more fuel into the crankcase. Now part of the cooling for our engines comes from the evaporation of fuel inside the crankcase and this includes all parts like (or especially) the inner surface of the piston. The more fuel the more evaporation the more internal cooling. So the piston interior gets more cooling and that compensates for any additional heat from the combustion process. That's why you can change nitro content (within reason) and not need any "running in".
One benefit of nitro is that it'll tolerate a huge range of acceptable air/fuel ratios, anywhere between about 2.5:1 and 0.5:1 which is a factor of 5 before it decides if it's a bit rich or a bit lean.
Stress on an engine comes mainly from centrifugal and acceleration forces. The slight extra load from higher combustion pressure is insignificant.
One benefit of nitro is that it'll tolerate a huge range of acceptable air/fuel ratios, anywhere between about 2.5:1 and 0.5:1 which is a factor of 5 before it decides if it's a bit rich or a bit lean.
Stress on an engine comes mainly from centrifugal and acceleration forces. The slight extra load from higher combustion pressure is insignificant.
10-03-2007, 08:54 AM
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RE: More Nitro Content?
Saying it's insignificant is not really true. That pressure is what produces power and power puts more stress on the materials.
Acceleration and centrifugal forces are the insignificant ones.
30000 rpm is 30000 rpm no matter how much power you produce, 0.5hp or 3hp.
Acceleration and centrifugal forces are the insignificant ones.
30000 rpm is 30000 rpm no matter how much power you produce, 0.5hp or 3hp.
10-03-2007, 09:37 AM
#23
RE: More Nitro Content?
Maximum cylinder pressure comes at the point of peak torque (which is why it's peak torque really) and declines after that. Adding nitro will boost the peak cylinder pressure at the same point but still decline at higher revs. At 30,000 revs piston acceleration is around 10,000 G's and at 35,000 it's up around 14,500 G's.
10-03-2007, 11:05 AM
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RE: More Nitro Content?
Wow! This thread just went crazy!!!! One thing I notice is that everyone has valid points but very few can agree!
Example: Does more nitro make the engine run hotter? Well, if you don't change mixture settings,,,,,,, yes! If you do change mixture, no!
Also, when piston/cylinder clearance exceeds spec you lose compressive abilities. This means less pressure! It can be compensated for by removing shims OR going hotter with the plug! The plug method is GOOD, shimming is BETTER, and replacement of the worn parts is BEST!
When it comes to stress in the engine, more energy= more stress! STRESS/TIME=STRAIN If you believe this statement then it is fare to say that parts designed for X amount of stress over time will indeed fail sooner if 2X stress is applied to them. That is why they make performance parts!
With all that said, can't we all just get along!
One thing I notice is that everyone has valid points but very few can agree!Example: Does more nitro make the engine run hotter? Well, if you don't change mixture settings,,,,,,, yes! If you do change mixture, no!
Also, when piston/cylinder clearance exceeds spec you lose compressive abilities. This means less pressure! It can be compensated for by removing shims OR going hotter with the plug! The plug method is GOOD, shimming is BETTER, and replacement of the worn parts is BEST!
When it comes to stress in the engine, more energy= more stress! STRESS/TIME=STRAIN If you believe this statement then it is fare to say that parts designed for X amount of stress over time will indeed fail sooner if 2X stress is applied to them. That is why they make performance parts!
With all that said, can't we all just get along!