NITROUS OXIDE ( nos / n2o ) advice forum

My opinion of the current Drag racing nitrous safety regulations (which have been in existence and remained unchanged despite advances in technology, for over 30 years, is that they are 'out dated and unsafe'.

I hope to change the regulations for the well being of all nitrous racers, so what I've done is taken a 'superior' concept and designed a new component, that when used to replace (or supplement) the existing 'blow off disc' will make not only the bottle safer but also the 'use' of the Nitrous system itself MUCH SAFER!!!!

Here are the problems with "blow off discs" that are required on all Nitrous bottles by existing regulations;

1) They are an unnecessary weak link in the system.

2) They are inconsistent and fail over a wide range of pressures.

3) When one fails, it results in a COMPLETE loss of the bottle contents (this could cost you as much as £80 of gas, plus the disc at £6, plus the travelling costs, plus the inconvenience).

4) Failure renders the bottle useless until a replacement disc is obtained and fitted (this could mean you are unable to continue in a race meeting or have to wait many days before you can use the system again).

5) Disc failure results in a rapid and total release of the bottle contents in LIQUID form which can result in freeze burning the user.

6) If the bottle is not secured to the brackets in the car, the sudden release of the pressure and force from the bottle can turn the bottle into an unguided missile.

7) The sudden release of pressure makes a very loud noise and will come as a shock to the driver of the vehicle, which can result in the loss of control of the vehicle.

8) MOST IMPORTANTLY, with a blow off disc the bottle pressure can exceed the intended safe working pressure that the system is jetted for. This means that too much Nitrous could be fed to the engine without an adequate amount of extra fuel, resulting in engine failure.


Here are some SPRVs

http://www.noswizard.com/admin1/image/6477SPRV.jpg

http://www.noswizard.com/product_desc.php?id=116

http://www.noswizard.com/product_desc.php?id=44


VIDEO CLIPS DEMONSTRATING THE PERFORMANCE OF A RUPTURE DISC COMPARED TO THE SPRV TO FOLLOW ASAP - SEE LATER POSTS.


Replacing or supplementing the 'blow off disc' with a 'Safe Pressure Relief Valve' (SPRV) has the following advantages;

1) The weak link is made adjustable to suit your requirements.

2) The SPRV is 100% consistent, reliable and produces repeatable results.

3) When the bottle pressure exceeds the safe pressure ONLY enough GAS to reduce the bottle pressure to the safe level is discharged (lost). This also has the advantage of reducing the bottle temperature, which will also reduce the bottle pressure, thus minimising the loss of gas and the risk of a repeat.

4) The loss of gas with a SPRV will cost you just a few pence not up to £80 as with the blow off disc.

5) When the bottle pressure exceeds the safe pressure, the system can still be used even if there is gas 'leaking down'. It will not result in a lost race or a weekends racing as with the blow off disc.

6) When the bottle pressure exceeds the safe pressure it results in a slow low pressure controlled release of ONLY the excess pressure.

7) When the bottle pressure exceeds the safe pressure there is NO sudden release of pressure and force so the bottle remains in it's normal safe and stable state.

8) There is no loud noise as the SPRV releases excess pressure, so there is no chance of a sudden loud noise distracting your driving and causing an accident.

9) With a SPRV the bottle pressure can be set so to prevent the gas pressure exceeding the intended safe working pressure, that the system is jetted for. This means that its impossible for too much Nitrous to be fed to the engine without an adequate amount of extra fuel, which will prevent an engine failure that would occur in the same situation if a rupture disc was in use instead of an SPRV.

10) Not only does the SPRV make the bottle much safer under normal system conditions but it also means that bottle heaters will now be a MUCH safer option, because it will be impossible for the heater to raise the pressure to the level that could burst the bottle, so we have introduced a heater as an optional extra to our systems now.

11) Furthermore for race applications it will now be possible to maintain a more constant bottle pressure for the full 1/4 mile with or without the aid of Nitrogen boosting.

12) A final advantage is that the user has control over what pressure their system works at.

ALL our systems have the SPRV as STANDARD fitment and they are available as an upgrade for other valves at £26

ANOTHER WORLD FIRST FROM HIGHPOWER SYSTEMS

hi trev.
can these valves be udjusted to say 900 p.s.i blow off and are these still available?.thanks

Yes & yes!!!

cool,,would it be able to be adjusted for me before its sent?,rather than me trying to do it and completly messing it up,,also out of interest would it being set that low interfere with the filling of the bottle,,i.e will it blow past at that setting as they are filling it?,,thanks wizard

rgds
warlock

Yes we can set it for you and no it won't cause any problems.

great.ok i shall be in contact on pay day.thanks alot trev your a diamond or is it a wise old owl....lol

Trev,
I have a rupture discs in my bottle, do i need to return the bottle to have the upgrade????

No you can fit the SPRV yourself.

You can either add the SPRV to the rupture disk as a catch net or you can remove/replace the rupture disk and use it to it's full potential.

Here's a clip demonstrating the difference between a rupture disc and an SPRV.

You'll notice the bottle on the left (with the rupture disc) is strapped to the post (for reasons you'll appreciate towards the end of the clip), but the bottle to the right (with the SPRV) is not, because the release of nitrous pressure from an SPRV is controlled and safe.

You will also notice that we have run a tube from the SPRV into a bottle of water. This is to highlight the small amount of nitrous being released as the pressure is increased, because the release is ONLY GAS (not liquid) and would otherwise be invisible. With a rupture disc there is no need to highlight the release of nitrous as you will see.

Also keep in mind that under normal conditions the SPRV would start to release at the slightest increase above the desired safe pressure setting and there would never be more than a trickle of nitrous gas released.

HIGH RES VIDEO CLIP
http://www.noswizard.com/videos/SPRV%20 ... 20last.wmv

LOW RES VIDEO CLIP
http://www.noswizard.com/videos/SPRV%20 ... 20disc.wmv

The SPRV is a MAJOR step forward in nitrous safety and in the prevention of wasting liquid nitrous in the event of an accidental increase in bottle pressure.

What was the pressure range of the SPRV equipped bottle?

How fast can the SPRV react to rising pressure?

No time to do the tests myself yet for my own answers.

Trev:

Are you saying i can add the valve to my NOS bottle? If that is a yes, what do you recommend it be set at, I run the bottle at 1000 psi.

The pressure range of the SPRV is from below 500 to in excess of 2,000 psi

For this demonstration the SPRV was set at 1,000 psi and AS SOON as the pressure was increased by the slightest amount the valve activated producing one or two small bubbles in the bottle of water. This was before the gauge registered a 50 psi increase and I have this on the original recording.
However to squeeze the recording down to an acceptable size, I had to save it as the lowest quality and cut it to cover just the essentials.

The pressure release is extremely fine and controlled at the lower end of the scale, where it would actually work under normal conditions, so I think I'll post another clip showing that as well.

We'll be manufacturing an adaptor to fit these to US bottles soon but for now the only way you can have one is to buy our complete bottle valve.

You'll have to look closely and listen closely to this one to get the full picture.

The sound is the nitrogen flowing through the regulator and this clip starts with the smallest amount actually flowing but it's very quiet and there are also one or two bubbles right at the start.

VIDEO CLIP TO FOLLOW ASAP

wow, thats seriously amazing stuff. Almost scary to think of the old design. What is the factroy pressure on these SPRV when supplied with your tanks?

How VERY TRUE, it's very scary when a rupture disc blows and it happens very often when people are heating bottles or in a hot summer.

The factory setting is approx. 1,200 psi but they are very simple to adjust to whatever you want.

Ahh ok great, more than one would ever expect in the UK then

Correct and just enough to avoid engine damage due to more nitrous being fed to the engine than is intended due to the pressure having got too high.

The SPRV is obviously extremely beneficial compared to even a good blow off disc (which are even then still unpredictable) but this link proves that some companies can't even get such a simple component manufactured correctly;

http://www.holley.com/HolleyNews/NOS%20 ... Notice.asp

The contents of this link also prove how IMPORTANT bottle pressure is and the EXTREME risks involved when it's not maintained correctly, so you'd think ALL companies would fit an SPRV to their bottles if they were really concerned more about their customers than their own profits.

Anyone wanting SUPERIOR product design and quality, should know where to come by now.

I've had your SPRV on my wish-list since first seeing the video you published on how rupture discs operate. As a safety device, I don't rate the rupture disc much but (similar to a fuse) where a weaker part will fail before the bottle bursts is better than nothing - unlike the competition bottles you've linked to. It beggars belief!

Here's a clip showing how FINE & SMALL the initial pressure release is from the SPRV.

LOW RES VIDEO CLIP
http://www.noswizard.com/trev/SPRV.wmv

I suggest you pick the enlarge to 800 option otherwise you can't see the bubbles.

As you can see (and hear), as the nitrogen increases the pressure even the slightest amount above the safe limit, the excess is released producing JUST ONE OR TWO bubbles - so much for those "experts" who proclaimed the gas release from the SPRV would be extremely dangerous.

By the end of the clip the nitrogen reg is making a lot of noise and the pressure is up to about 1,200 psi, with the SPRV releasing a relatively large volume of nitrous gas to get the pressure back down. However because the nitrogen is being constantly fed to the bottle at a higher rate that the SPRV can release it the pressure in the bottle rises.
Under normal conditions that would not be the case, as the cause for the rise in pressure would not be able to match the nitrogen boost we're using for the demo. We've had bottles sat inches away from a 5KW heater and the SPRV has kept the pressure within safe limits.

Keep in mind that unless the heat input is greater than the combination of the pressure released and the consequential drop in temp from releasing a SMALL amount of nitrous GAS, this is ALL that will EVER be released from the bottle.

The original clip I posted earlier in the thread, shows the SPRV performing under ARTIFICIALLY EXTREME & EXTREMELY UNLIKELY conditions, just to demonstrate the difference between how it performs compared to a rupture disc, up to the point when a rupture disc would fail.

I now intend to do a few more clips to demonstrate the benefits in real world scenarios.

Watch this space.

Hi

I had an SPRV on my first bottle and had heater problems (the problem being I am old and forgot to wire it into an ignition feed ) so it heated permanently lol...

So there I was happily motoring along and heard this very gently hiss noise that stopped after a few seconds....

After several times, I finally thought...hmmm..lets have a look at my bottle gauge...

It was at around 1100 psi

The gently hissing was just the SPRV releasing small amounts of pressure PRECISELY as it was intended to do....no fuss...no blowing off a rupture disc and losing a whole bottle

I then turned OFF my bottle heater and all was well....

I would NEVER EVER EVER use a bottle without an SPRV after that......

I really cannot understand why other companies still continue to us old fashioned blow off discs

Cannot be bothered ??

Cannot admit Trev is right ??

Dont care about customers safety ??

All the best Brett

last year i forgot my bottle in the boot. direct in the sun! 40°C outside. in the Car 50° or much more.
the SPRV:

sssssss....

thanks to Trev and the SPRV

Thanks for the INDEPENDENT input guys, as your comments are more likely to get the message home than mine.