Brett, I hope you meet your objectives and you stay safe.

 

Replacing bottles would suck and IIRC N2O setups, on most cars, are only activated at WOT. While boost on the other hand, can be achived at low throttle. No thanks.

 

From a popular website, you can see the obvious here.

http://encyclopedia.airliquide.com/E...a.asp?GasID=55

at just above the boiling point of NOS going from a gas to a liquid, its density is still near 1000times that of what it would be as a gas. even the temp difference of boiling point vs 59degrees F, is a factor of 3.
If NOS can be injected directly in the intake, there is no doubt that the HP potential is well over what Z has said is a limitation.

mk


For NOS:

Liquid phase

Liquid density (1.013 bar at boiling point) : 1222.8 kg/m3
Liquid/gas equivalent (1.013 bar and 15 °C (59 °F)) : 662 vol/vol
Boiling point (1.013 bar) : -88.5 °C
Latent heat of vaporization (1.013 bar at boiling point) : 376.14 kJ/kg
Vapor pressure (at 20 °C or 68 °F) : 58.5 bar
Critical pointCritical temperature : 36.4 °C
Critical pressure : 72.45 bar


Gaseous phase

Gas density (1.013 bar at boiling point) : 3.16 kg/m3
Gas density (1.013 bar and 15 °C (59 °F)) : 1.872 kg/m3
Compressibility Factor (Z) (1.013 bar and 15 °C (59 °F)) : 0.9939



For Air:

Liquid phase

Liquid density (1.013 bar at boiling point) : 875 kg/m3
Boiling point (incipient boiling point) : -194.5 °C
Latent heat of vaporization (1.013 bar at boiling point) : 198.7 kJ/kg
Critical pointCritical temperature : -140.5 °C
Critical pressure : 37.71 bar

Gaseous phase

Gas density (1.013 bar at boiling point) : 3.2 kg/m3
Gas density (1.013 bar and 15 °C (59 °F)) : 1.202 kg/m3
Compressibility Factor (Z) (1.013 bar and 15 °C (59 °F)) : 0.9992
Specific gravity (air = 1) (1.013 bar and 21 °C (70 °F)) : 1
Specific volume (1.013 bar and 21 °C (70 °F)) : 0.833 m3/kg

 

+1...please keep us posted.

 

Mark,

You can't even correctly interpret the data that you yourself provided. If you could, you'd realize that it helps show that it's impossible for that engine to make 1,350hp, even in a best case situation, and while completely ignoring other factors that will reduce the power output even further from the theoretical maximum when using just nitrous. It's too bad that we'll never see a dyno chart, although explanations of why the dyno chart showing nowhere near 1,350hp would be wrong could be pretty entertaining.

 

Hi

And the world is still flat ???? lollll

All the best Brett

 

Z, you are wrong. I've seen 2.3 liter engines pull ~500rwhp running on nitrous alone. I'm not saying Brett's engine won't blow up, but he can definitely generate over 1000hp from his 4.7 liter engine if it holds together. Please stop making negative comments on something that really is much more complex than it seems on the surface.

Dan
'86 928S 5-spd w/LSD

 

Some of know Z's background on this subject

 

Perhaps this relates to different horses, like the ones the carnival barker implores you to see. G

 

Z, all I am interpreting is that NOS in vapor form is going to be much more dense than air alone. Im stating this, as you assumption is that the only difference between NOS and normal air flow to the engine, is the 50% difference in O2 content. this is far from the truth. not only is there a temperature difference, giving greater density, there is a "state" difference, where if the NOS is injected to an engine on the intake phase, the density would be 3x + that of air, just as it turned to a vapor as seen by the information ive provided If you can get 3x the density of the NOS in the combustion chamber, PLUS the 50% greater O2 content, that would equal a theroetical 1500HP. (if the NOS was matched with gasoline in the appropriate ratio)

Edit: if you look at the chart, even if NOS was injected at the same temp (like running an engine in a room filled with NOS instead of air) the density of NOS is again, another 50% more dense than air. SO, thats 50% more density at room tempurature, and 50% more oxygen. thats 100% more oxygen apples to apples or the same volume flow. So, if you have 300hp with air, it means that 600hp with just pure NOS and required fuel, is possible with out any changes. now, to meet the 1350hp range, just a drop in tempurature to double density would be required. if you understand how cold and vapourous NOS is out of the bottle under 1000psi, the theory is easy to understand. comments????? am I off base here??

you keep on insinuating that there might not be "room" for the mass flow.
This couldnt be futher from the truth. There is plenty of room for 1500hp worth of mass flow in an internal combustion engine in the 5 liter size.
Dragsters that produce near 5000hp are said to be on the verge of Hydrolock with their fuel and air load, out of engines only 50% larger than the 5 liter in question.

The point here, and correct me if im wrong (as you say i cant even interpret the data properly), but if NOS can be injected from a 1000psi source, (as it can) and that is pushed in via atomospheric pressure of near 1bar, it will have at least 3x more mass than air, for the same volume. by volume, the additional fuel is a fraction greater as well being that its massflow is 1/12th that of the increased air flow, as well as it being in an near vapor state as well.

Now, I am not interpreting anything more than the basic facts of NOS (cold and more dense than just air ) vs air . It is no different than what the power results would be if you were able to increase the pressure density with a supercharger to 3 bar, and add the fuel. this is certainly possible. heck, the Evo makes 550hp with a 2.4 liter and races a full year this way. the Japanese pro version makes near 700hp out of the same displacement. CART has been doing this for years. NOS is just a cheating way to bypass all the mechanics to create such densitys chemically vs mechanically. again, im sure its not possible that it can be done with our engines practically, but it can in theory, certainly not limited by your interpreted limitations!

If NOS enters the engine at a min. 3x the density and has 50% more oxygen (actually 100% more with the fact that NOS is 50% more dense even at the same temp as air) , why wouldnt the engine not make near 1500hp, if all structural and combustion factors were ignored?

as a note, when you talk about "nitrous alone" you are surely talking about NOS plus fuel, right. NOS without fuel wouldnt do much.

mk

 

Hi Brett, pulling for you to achieve your goal!!!

I have a question about your aerodynamics: ARe you going to do this record attempt with stock S2 bodywork? Are you going to tape up the seams, remove mirrors, etc? Or just go as is? Since you could probably achieve your top speed goals with far less than 1350 hp if your car was very aerodynamic, is all the extra power to force the S2 shape thru the air at that speed? Do you think it will be aerodynamically stable enough? Thought about adding S4 bodywork or at least a wing? (recall the all the aerodynamics discussion in the 'removing the wing' thread here)

I recall a family of ORR guys named Goetlib (or something like that) who got a '68 Camero to go 220 mph with a huge Chevy crate motor a few years back, so I suppose anything is possible.

Look forward to reading about your success! (any chance of in-car video for the run?)
-Chris

 

On second thought, if you were a crew chief for a drag racing team in the 80's, you've gotten less aerodynamic things to go faster than that (if only for a few seconds) so this probably familiar territory to you

 

NOS is twice as dense at same tempurature, as well as having 50% more oxygen. PLus, we are talking about an intake charge much cooler, so much more dense than air. the fact that intake charges are reduced in tempurature by 70degrees F, is an indication of how much the temp will drop if an engine was powered by NOS/fuel alone. (thats with a mixture of 75% air and 25% NOS) the boiling point (where NOS turns to gas) is - 90degrees C so it doesnt take a stretch to see that the potential for 1500hp is possible out of a 5 liter based on what is done today.

Mk

 

Yes, double the oxygen if air was totally replaced with NOS. as I said, NOS at the same temp is 50% more dense than air, and has 50% more oxygen.
At the point where NOS turns into a gas (as it is released from the bottle) it is 3x more dense as air. all we need is double the density due to tempurature, and that certainly is plausible to meet the 1350hp theoretical goal.

So, your statement below is incorrect.

Mk

 

Hi Chris

I did speak to an expert in aerodynamics about the 928 and gave him all the drawings ,measurements etc...

His conclusion was...to improve it ,I would need 2 NACA style ducts at the BACK of the bonnet (hood) just in front of the screen and another 2 on TOP of car near the back of roof...

He also said there were 2 ways to get to very high speed....good aerodynamics OR HUGE amounts of hp...in which case the aerodynamics dont matter much..lol

I think you can guess which way I am going...

I may take off the wipers, mirrors and tape seams etc but cutting big holes in my bonnet and roof for Naca ducts on my daily driver is not really on

My dash already looks like "Back to the future" ,I dont really want the outside looking the same

And you are correct, a Top Fuel dragster is not the most aerodynamic thing in the world but the hp makes up for that...

All the best Brett