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totopo · 12-16-2015, 03:41 PM

Jeez man, what's the hate? Why is one side posting nothing but meme's and sarcasm and hate? I feel like the snarky comments are completely unfounded, add nothing to the discussion, and haven't been backed up with anything. When I go back and read this thread, it seems like there are a few people being reasonable, and then a bunch of people trying to derail the thread.

The question of is nitrous FI is kind of debated back and forth on various forums and it is really a stupid argument if you understand it. It's nitrous, it's not really NA, or FI.

Why did this question come about? Because CSG Mike claimed that there was a 300whp NA fa20 (implying stock bottom), and that a 300whp NA engine wouldn't need strengthened rods, then when challenged (it'll probably never happen, and never happen on a stock bottom;i explained it in a post back on page 2 or 3 or something), backed up and said it was on nitrous.

So to kind of back up, and why this argument is stupid, conceptually, there are only so many ways to get more HP out of an engine. You can suck in more air (displacement/FI), you can burn your air more efficiently (MBT), you can compress your air fuel mixture more (octane/e85/methanol), or you can rev higher.

So what does nitrous do? it does multiple things. It cools the intake temperature, which increase both the efficiency and the amount of oxygen. It then provides more oxygen into the system to burn when the 02 is dissociated from the nitrogen. Then it lets you compress your mixture more because of the knock retardation. It is completely different than fuel, it's the opposite side. To do work, you burn fuel in the presence of an oxidizer. Nitrous is the oxidizer, not the fuel. Like take for example a rocket engine (that doesn't consume atmospheric oxygen. One such liquid rocket fuel is nitrous oxide fuel blend. (https://en.wikipedia.org/wiki/Nitrous_oxide_fuel_blend). This completely uses nitrous oxide as the sole source of oxidizer (oxygen).

So to bring it back to what does it mean for engine internals, or specifically the rod. So what the rod sees is pressure, not power. When you need to strengthen the rod is when you have high pressure, not power. If you don't believe me, look back and find the one cosworth post and you notice how he talks about cylinder pressure as the tuning limit on a stock block, not power.

So the difference between FI and NA in terms of overall engine tuning is that they get power in different ways. FI gets more power easier by shoving tons of air. With more air you can burn more fuel. With more air and fuel you get bigger booms. This equates to increased pressure in the cylinder, which pushes on the rods, which eventually gets converted to TORQUE, which minus heat losses turns into power@rpm. NA is limited by the amount of oxygen it can get. There is only so much pressure you can develop. An F1 or nascar engine can only develop so much torque/volume, much less than an FI. So what NA focuses on is getting the highest pressure (BMEP/Torque), then not losing it and revving to the sky, which gets you power.

So which is nitrous more similar to? In my eyes, it is not really equal to either, but in terms of engine design, if you want to run nitrous, it needs beefier internals like FI because it increases pressure phenomenally, which is what fails the rods. So if someone asks "Is nitrous FI or NA" and I don't want to go into the effort saying/type the above, I would say FI, when I don't think it's really the same.

So if CSG Mike says there is a 300whp Nitrous "NA" engine out there. Then I would say yes, it needs stronger internals just the same as a 300whp FI engine, since they are probably developing similar torque.

edit: also, N20 is 36% oxygen, not 33%

edit 2: retarded "typo"

edit 3: the 33% nitrous by molarity is more applicable than by mass, so I would take back edit 1, haha

12-16-2015, 03:41 PM	#201
totopo Senior Member Join Date: May 2014 Drives: 370z Location: california Posts: 364 Thanks: 162 Thanked 299 Times in 156 Posts Mentioned: 4 Post(s) Tagged: 1 Thread(s)	Jeez man, what's the hate? Why is one side posting nothing but meme's and sarcasm and hate? I feel like the snarky comments are completely unfounded, add nothing to the discussion, and haven't been backed up with anything. When I go back and read this thread, it seems like there are a few people being reasonable, and then a bunch of people trying to derail the thread. The question of is nitrous FI is kind of debated back and forth on various forums and it is really a stupid argument if you understand it. It's nitrous, it's not really NA, or FI. Why did this question come about? Because CSG Mike claimed that there was a 300whp NA fa20 (implying stock bottom), and that a 300whp NA engine wouldn't need strengthened rods, then when challenged (it'll probably never happen, and never happen on a stock bottom;i explained it in a post back on page 2 or 3 or something), backed up and said it was on nitrous. So to kind of back up, and why this argument is stupid, conceptually, there are only so many ways to get more HP out of an engine. You can suck in more air (displacement/FI), you can burn your air more efficiently (MBT), you can compress your air fuel mixture more (octane/e85/methanol), or you can rev higher. So what does nitrous do? it does multiple things. It cools the intake temperature, which increase both the efficiency and the amount of oxygen. It then provides more oxygen into the system to burn when the 02 is dissociated from the nitrogen. Then it lets you compress your mixture more because of the knock retardation. It is completely different than fuel, it's the opposite side. To do work, you burn fuel in the presence of an oxidizer. Nitrous is the oxidizer, not the fuel. Like take for example a rocket engine (that doesn't consume atmospheric oxygen. One such liquid rocket fuel is nitrous oxide fuel blend. (https://en.wikipedia.org/wiki/Nitrous_oxide_fuel_blend). This completely uses nitrous oxide as the sole source of oxidizer (oxygen). So to bring it back to what does it mean for engine internals, or specifically the rod. So what the rod sees is pressure, not power. When you need to strengthen the rod is when you have high pressure, not power. If you don't believe me, look back and find the one cosworth post and you notice how he talks about cylinder pressure as the tuning limit on a stock block, not power. So the difference between FI and NA in terms of overall engine tuning is that they get power in different ways. FI gets more power easier by shoving tons of air. With more air you can burn more fuel. With more air and fuel you get bigger booms. This equates to increased pressure in the cylinder, which pushes on the rods, which eventually gets converted to TORQUE, which minus heat losses turns into power@rpm. NA is limited by the amount of oxygen it can get. There is only so much pressure you can develop. An F1 or nascar engine can only develop so much torque/volume, much less than an FI. So what NA focuses on is getting the highest pressure (BMEP/Torque), then not losing it and revving to the sky, which gets you power. So which is nitrous more similar to? In my eyes, it is not really equal to either, but in terms of engine design, if you want to run nitrous, it needs beefier internals like FI because it increases pressure phenomenally, which is what fails the rods. So if someone asks "Is nitrous FI or NA" and I don't want to go into the effort saying/type the above, I would say FI, when I don't think it's really the same. So if CSG Mike says there is a 300whp Nitrous "NA" engine out there. Then I would say yes, it needs stronger internals just the same as a 300whp FI engine, since they are probably developing similar torque. edit: also, N20 is 36% oxygen, not 33% edit 2: retarded "typo" edit 3: the 33% nitrous by molarity is more applicable than by mass, so I would take back edit 1, haha Last edited by totopo; 12-16-2015 at 07:27 PM.