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+--- Thread: Nitrous is good! (/showthread.php?tid=7201)
Nitrous is good! - TurboTim - 05-08-2016
Just installed nitrous on my OM606 and am loving it! Now I can confidently race anything and know I will win. I run an HE351VE and so it's not a super big turbo but it does have some lag. I guess I am around 430hp. With a 100 shot I can roll on second and this thing spins the tires like it's my 619HP CL65. Lag is gone. Having another 100hp is nice. EGT's seem to be down because now my turbo is boosting higher. I really love nitrous on diesel because you don't have to worry about bottle pressure being low and being pig rich. As far as I know I can hit it pretty low and not have to worry about anything either. If anyone it running a bigger turbo then they like I highly suggest spray! The end..
RE: Nitrous is good! - Dark Hawk - 05-09-2016
What made you choose nitrous over propane? Just curious
RE: Nitrous is good! - TurboTim - 05-09-2016
Propane is a fuel. Nitrous is a power adder. 2 completely different things.
RE: Nitrous is good! - R-3350 - 05-09-2016
one of the limitations of diesel is the extremely slow speed of combustion (this is one of the main reasons diesel engines turn slower than gas also the higher stresses involved in compression ignition make the components heavier). increasing the oxygen content of a fuel mixture tends to increase the flame propagation speed. thus nitrous can increase the efficiency of the combustion process for diesel. lower EGT and more power however peak combustion pressure increases due to the faster burn. also n20 is not very cheap and available unlike propane which is one thing to factor if you want to commonly use it. they both have good and bad its up to what you want to do.
RE: Nitrous is good! - Tito - 05-09-2016
How does nitro on a diesel work? I've heard it falls apart in oxygen when burned. So, you'll need more fuel. If it's combustable it would set fire while on the compression stroke giving heavy knocking right?
RE: Nitrous is good! - R-3350 - 05-09-2016
it increases the oxygen content of the intake charge while also cooling it rapidly. normal air is about 20% O2 while nitrous is N2O thus its 33% oxygen by weight. its also a liquid when its in the bottle when you spray it it boils rapidly into a gas cooling the air charge. the cold high oxygen intake charge lets you burn a great deal more fuel than you could normally. in a gas engine you spray nitrous while adding more fuel too to increase power. in a diesel it will let you burn the fuel you would normally need a lot of boost to burn cleanly. it also increases the efficiency of the burn as i explained earlier. thus more power without waiting for your turbo to spool.
RE: Nitrous is good! - [486] - 05-09-2016
Nitrous when you don't have enough air
Propane when you don't have enough fuel, and don't know any better
A little propane can help efficiency, but if you're using it for a power adder you're going to hurt things. There's a reason diesels have such a thing as "injection timing". With fuel into the intake, it doesn't have anything saying when it lights.
For that matter, careful with the nitrous, VERY easy to get far too much torque going on when you're low in RPMs. Rods buckle, bearings get spun, clutches get slipped, trans hard parts break... With more revs you can sneak more horsepower through the engine and trans with less stress on the bits. The torque limiter in the pump (or in the ECU maps) is your very good friend.
RE: Nitrous is good! - MFSuper90 - 05-09-2016
Also be careful of cylinder pressure and exhaust back pressure with nitrous, the faster burn in turn creates high cylinder pressures (not to mention to added boost) which in turn can make some super high back pressure. If you check around lots of the diesel guys that shoot abunch of NOS have very large external gates.
Pretty cool because the external gate sometimes has its own exhaust pipe and it will shoot fire out of it haha
But nitrous is low doses can be really awesome!
RE: Nitrous is good! - baldur - 05-10-2016
(05-09-2016, 12:46 PM)R-3350 one of the limitations of diesel is the extremely slow speed of combustion (this is one of the main reasons diesel engines turn slower than gas also the higher stresses involved in compression ignition make the components heavier). increasing the oxygen content of a fuel mixture tends to increase the flame propagation speed. thus nitrous can increase the efficiency of the combustion process for diesel. lower EGT and more power however peak combustion pressure increases due to the faster burn. also n20 is not very cheap and available unlike propane which is one thing to factor if you want to commonly use it. they both have good and bad its up to what you want to do.
Diesels do NOT have slow combustion. They have a very fast and violent combustion which is why they need such heavy duty components. In fact the fast combustion is one of the components to an efficient engine, it increases the surface area inside the P-V plot. Petrol engines have slow combustion, that's why they need to ignite the fuel some 30 degrees before TDC for best performance (Some need less, some need as much as 40-50 degrees).
RE: Nitrous is good! - TurboTim - 05-10-2016
(05-09-2016, 11:29 PM)MFSuper90 Also be careful of cylinder pressure and exhaust back pressure with nitrous, the faster burn in turn creates high cylinder pressures (not to mention to added boost) which in turn can make some super high back pressure. If you check around lots of the diesel guys that shoot abunch of NOS have very large external gates.
Pretty cool because the external gate sometimes has its own exhaust pipe and it will shoot fire out of it haha
But nitrous is low doses can be really awesome!
I run a VGT turbo so my boost goes higher but back pressure stays the same. I think it makes 35psi with 30 EGP.
RE: Nitrous is good! - Dark Hawk - 05-10-2016
Thanks guys, lots of good information in this thread.
Does anyone have any experience with om617 and nitrous? Biggest safe shot, ect?
RE: Nitrous is good! - MFSuper90 - 05-10-2016
(05-10-2016, 11:42 AM)Dark Hawk Thanks guys, lots of good information in this thread.
Does anyone have any experience with om617 and nitrous? Biggest safe shot, ect?
Since nitrous is oxygen, I think you would have a tough time picking up a decent amount of hp because of the lack of fuel the stock MW could supply.
But I could be wrong! That's just my thinking
RE: Nitrous is good! - R-3350 - 05-11-2016
the sound of a diesel has to do with the non linear ignition of the fuel. it doesn't start combustion from one place only and propagate from there. thus the peak combustion pressure is reached faster. the flame propagation speed of a fuel air mixture in diesel is difficult to quantify due to the wildly differing mixtures and ignition conditions existing in the cylinders. the fuel micro droplets from the injectors have a rich mixture surrounding them while the bulk air is a very lean mixture. however when compared in a lab the flame speed of diesel is around 40-100cm/s depending on temperature and pressure this is significantly slower than gas which is around 10-20m/s. that being said all this is very dependent on the conditions of the fuel mixture. for the most part this is overcome in engines due to the compression ignition initiating combustion from multiple points simultaneously. however it becomes a large factor when trying to complete combustion at high velocities. this is why diesels don't make much power at high rpm even when the engine has been optimized to deliver air at these quantities and speeds.
http://www.sciencedirect.com/science/article/pii/S1540748910002695
www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA433310
RE: Nitrous is good! - atypicalguy - 05-11-2016
Always a drag when the atmosphere ignites. Reminds me of the h bomb guys trying to make sure they would not ignite the earth's atmosphere and burn it completely up. Turned out not to be able to maintain combustion due to dissipation of heat etc. Thankfully.
RE: Nitrous is good! - baldur - 05-11-2016
(05-11-2016, 12:54 AM)R-3350 the sound of a diesel has to do with the non linear ignition of the fuel. it doesn't start combustion from one place only and propagate from there. thus the peak combustion pressure is reached faster. the flame propagation speed of a fuel air mixture in diesel is difficult to quantify due to the wildly differing mixtures and ignition conditions existing in the cylinders. the fuel micro droplets from the injectors have a rich mixture surrounding them while the bulk air is a very lean mixture. however when compared in a lab the flame speed of diesel is around 40-100cm/s depending on temperature and pressure this is significantly slower than gas which is around 10-20m/s. that being said all this is very dependent on the conditions of the fuel mixture. for the most part this is overcome in engines due to the compression ignition initiating combustion from multiple points simultaneously. however it becomes a large factor when trying to complete combustion at high velocities. this is why diesels don't make much power at high rpm even when the engine has been optimized to deliver air at these quantities and speeds.
http://www.sciencedirect.com/science/article/pii/S1540748910002695
www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA433310
Yes, but the laminar flame speed has almost no relation to speed of combustion inside an engine, where in the case of spark ignition, flame propagation happens by convection and depends mostly on the turbulence present in the chamber (with high turbulence the surface area exposing unburned mixture to heat becomes greater). And since the diesel initiates combustion in a completely different manner you cannot compare the laminar flame speeds of the fuels and think that has something to do with anything.
Of course, a diesel just like a petrol engine will need considerable modification for best performance at speeds far greater than it was originally designed for. Part of that is optimizing the combustion, a fast burn requires short injection duration and small droplets (high injection pressure). Some attention must also be given to how well the fuel mist mixes with the air in the chamber to maximise the yield of the air/fuel without producing soot.
RE: Nitrous is good! - R-3350 - 05-11-2016
i understand the laminar flame speed is not a good measurement of the characteristics of combustion in real world situations. however it does help to explain the poor combustion in diesels running over ~6000 rpm. very few diesels can be made to continue making power at those speeds. usually there is a sharp drop in output combined with a rapid rise in EGT once you exceed the ability of the fuel to combust in the time between TDC and BDC. while gas engines are mostly limited by fluid flow characteristics at high speed. look at what happens to a gas engine when you switch from petro fuel to methanol without adding timing only adjusting the AFR for the new fuel you gain a little power due to the faster combustion of methanol vs isooctane.
RE: Nitrous is good! - LewisG95 - 05-17-2016
I definitely have some interest in this thread! I work for a nitrous oxide company in the UK and will be planning to put one of our spare kits onto my 605 if/when i get the ECU chip and bigger turbo sorted. We have seen a huge number of good results on diesels with our systems and three of the major companies in the UK and europe use our systems on VAG diesels.
But yeah, i definitely want to get gas on my merc
RE: Nitrous is good! - hooblah - 05-17-2016
RE: Nitrous is good! - LewisG95 - 05-17-2016
That's us ^^