how long will the bottle last?

[SharkAttak]

when running nos, on average how long will a bottle last?

 

[ROCKERDAN]

Not positive on this as Im new to NOS game...but Im hearing you might get about FOUR 8second shots out of the 2.5lb bottle...so for radaring this is perfect...4 runs you should be able to dial in and run some serious speeds...

most guys have 2 bottles,so you can swap out to a full bottle...also,you can have a 10lb mother tank in truck,to fill sled tanks.

Dan

 

[SharkAttak]

Not positive on this as Im new to NOS game...but Im hearing you might get about FOUR 8second shots out of the 2.5lb bottle...so for radaring this is perfect...4 runs you should be able to dial in and run some serious speeds...

most guys have 2 bottles,so you can swap out to a full bottle...also,you can have a 10lb mother tank in truck,to fill sled tanks.

Dan

thanks Dan, let us know how you make out with the nos and take some pic's of the install, i'm really interested in doing to my attak next season

 

[Blown14psi]

I've posted this before, but it depends on how much HP

Checkout page 5

http://www.holley.com/data/Products/Tec ... 8-SNOS.pdf


I wish Holtzman, BOSS, and BD gave their customers technical data like this.

 

[SharkAttak]

thanks

 

[BlueMax]

The formula for calculating nos usage is:

Time in seconds =(Tank size of NOS in lbs.) divided by (0.0008 multiplied by the horsepower increase)

Here is an example:

2.5 lb. bottle
90 horsepower

Time in seconds = 2.5/(0.0008 X 90) = 34.7 seconds

Hope this helps.

 

[Blown14psi]

Then why do I only get 40 sec out of a 50hp hit I'm using N.O.S. and Holleys info seems right on for me.

50hp is 2.5lb bottle/.6lbs in 10 sec = 4.17 ten sec hits or about 42 sec total.

90hp would be 2.5lb bottle/1.08 in 10 sec = 2.31 ten sec hits or 23 sec total.


BlueMax Where did you get that info seems a little off to me?

 

[BlueMax]

BlueMax Where did you get that info seems a little off to me?

The amount of fuel used in a modern 4 stroke engine is 0.5 lbs. per horsepower per hour. The ideal air fuel ratio using normal air is 14.7 to 1. When using NOS, the ideal NOS to fuel ratio is 9.7 to 1. Most commercial tuners shoot for 5.5 to 6.0 to 1 to stay on the safe side.

So if you want to convert my fuel usage to lbs per second per horsepower, you divide the 0.5 by 3600.

0.5/3600 = 0.000139 lbs. per second per horsepower.

Multiply the NOS to fuel ratio (since this is by weight or mass) times the fuel usage and you get from 0.00076 to 0.00083 lbs of NOS per sec per horsepower. I rounded it off to 0.0008 in my equation.

So my equation ended up:

Time in seconds =(Tank size of NOS in lbs.) divided by (0.0008 multiplied by the horsepower increase)

 

[Blown14psi]

Interesting?

 

[Blown14psi]

Multiply the NOS to fuel ratio (since this is by weight or mass) times the fuel usage and you get from 0.00076 to 0.00083 lbs of NOS per sec per horsepower. I rounded it off to 0.0008 in my equation.

That's where you are off.

If you go by your 9.7 to 1 that's 9.7 N2O multiplied by 0.000139 fuel per sec = .0013483 N2O per HP/sec not .0008

so a 2.5 lb bottle / (.00135 times 50HP)= 37.037 or

2.5/(.00135 times 90HP) = 20.57 sec. That is closer to the Holley tech info that I've already referenced they've just already done that math for you and given you the nitrous per hp in 10 sec number.

That's the first I've ever hear of 9.7:1 ideal or a conservative 5.5 to 6:1 ratio.

I've always heard that the engine on the juice if you tune with a wideband should be between 11 and 12:1

Are you referring to the actual Nitrous to fuel at the nozzle if so that may be true, and if you use 9.7:1 then the math you stated is closer to Holley's tech info. I'm interested in your references?

 

[BlueMax]

That's where you are off.

If you go by your 9.7 to 1 that's 9.7 N2O multiplied by 0.000139 fuel per sec = .0013483 N2O per HP/sec not .0008

so a 2.5 lb bottle / (.00135 times 50HP)= 37.037 or

2.5/(.00135 times 90HP) = 20.57 sec. That is closer to the Holley tech info that I've already referenced they've just already done that math for you and given you the nitrous per hp in 10 sec number.

That's the first I've ever hear of 9.7:1 ideal or a conservative 5.5 to 6:1 ratio.

I've always heard that the engine on the juice if you tune with a wideband should be between 11 and 12:1

Are you referring to the actual Nitrous to fuel at the nozzle if so that may be true, and if you use 9.7:1 then the math you stated is closer to Holley's tech info. I'm interested in your references?

The 9.7 to 1 is the ideal NOS to fuel ratio by weight or mass. Those ratios (or those approaching that ideal number) can be used when combined with good monitoring equipment (good fuel also) for racing purposes and will produce more horsepower. Most companies that supply NOS kits to the public for street use work in the 5.5 to 6 range to allow for fuel quality variations, fuel delivery issues and etc.

The problem with NOS is cooling the engine when you start injecting too large of shot. When a engine is running on standard air at 14.7 to 1 (lets use the ideal numbers for a comparison), the 14.7 pounds of air is roughly made up of 11.2 pounds of nitrogen and 3.5 pounds of oxygen. This 11.2 pounds of nitrogen absorbs a lot of heat during combustion and is sent out the exhaust system. If we look at the NOS make up at 9.7 to 1, you have 6.2 pounds of nitrogen and the same 3.5 pounds of oxygen. So you can see with the NOS combustion you have only 55% of the cooling from nitrogen as compared by normal air combustion. As I stated earlier, a rate of 0.5 lbs of fuel per hour produces one horsepower in a normal internal combustion engine. In this case 1.0 pound of fuel per hour combined with 3.5 pounds of oxygen per hour produce 2.0 horsepower with either normal air or NOS. For a comparison, Pro Stock cars operate at 0.4 pounds of fuel per hour per horsepower or less and a supercharged or turbocharged engine are at 0.6 lbs per hour per horsepower.

There is also another horsepower adder achieved when using NOS. The NOS is injected into the air intake air flow as a liquid and when it changes states from liquid to gas a large source of energy is required. The energy is taken from the incoming air charge which is at ambient temperature. This reaction lowers the temperature of the incoming air charge by as much as 60 to 70 degrees f. For each 10 degrees of lower intake charge temperature, there is approximately a 1% increase in overall horsepower.

I have been working with NOS for some time and have quite a pile of my own information and engine parts. Most of this info is not readily available from the system manufacturers because it basically gives you the design parameters for your own NOS system. Hope this helps.