NITROUS OXIDE ( nos / n2o ) advice forum

Here i am once more complaining about another nos setup issue.

This time it regards how ineffective the system is, almost not even worth using it! I'll try to be as specific as possible with as many details and what others think may be causing my system be so poorly performing.

Vehicle is a 2 litre, straight 4, naturally aspirated RenaultSport Clio 197 2008 model.

Nitrous setup is an 11b bottle with bottle heater/pressure gauge, nylon supply line, x-10 pulsoids and single point injection being controlled by a Max Extreme Street. The nylon line runs inside the car right to the bulkhead. 'Professionally' fitted by Julian at Active Nitrous.

Now the reasons for my concern is because my other half has the previous generation clio with the SAME engine in it, her setup includes 11b bottle with no heater, braided line, no purge kit, minimax controller, standard pulsoids and single point injection in same location as mine. Supply line is also plumbed through the same route.

When she uses her nitrous on the road you can feel the spray kick in much like a turbo coming on boost and the car just shoots away, spinning wheels all the way up through 3rd gear. Its an absolute animal and she has beaten some seriously impressive cars on the strip, recording a mid 14's average.

When i use mine, well firstly its doubtful whether the system has actually activated or not at first, but after a longggg delay you can notice a VERY gentle and smooth surge in power mid range which almost immediately tails off at higher rpm, almost like your gunning it with the handbrake half on and then release it to feel the car pull a little better. It does seem that the longer you hold it on the less effective it works, after two gears its having zero effect on power. Both cars are set on the identical start power and build time.

Okay heres the test i carried out last night to help you all out to understand:
My car in 4th gear at 56mph, pulling exactly 4000rpm. I then test ran the car with no nitrous to record how long it took to get upto 7000rpm ( approx 85mph ). Without nitrous it was 10 seconds. I then re ran the test on the same strech of road immediately but with nitrous on, the bottle is full and showing 950psi on the gauge exactly, bottle heater being on for at least 20 minutes. It took the car 8 seconds, a mere 2 seconds less. I then reduced build time on the controller from 2 seconds to 1 second. The next test recorded 7 seconds, one second quicker.


Next I'll show you a few pics of the two different systems to identify any problems and also go through some common ideas other nitrous 'pros' have highlighted to me at a recent airfield drag day.

Thanks.

First up my system.

someone mentioned the roots to all my problems lay in the position my bottle is mounted, transversely:





Describing that as the car accelerated the nitrous was being forced back and the dip tube was drawing up the useless gas. After seeking advice on here i tested mounting the bottle at various angle within the bracket ( outlet at 6 o'clock, 7 and even 8 rearwards to the car ) all of which had no performance advantage, so i settled on 6 o'clock position.

Next problem is that my delivery pipes under the bonnet are too long, causing long delays in from the pulsoids and delivering just gas. Note: please ignore the braided line and old pulsoids, this is an old picture and i have since fitted a nylon line.





The line also comes from the bulkhead and over the exhaust manifold, but i've been told because the distance is so short it isnt enough to effect the nitrous from the heat, i have however heat wrapped excessively to protect it.

Been there, so I know its frustrating.
Firstly, Its NOT the position of the bottle and those are NOT long lines.
What size jets are installed?

But why have you connected the NOS to the Black Pulsoid in one car and not in the other?

Now a couple of pictures of the other system which should provide less results ( braided line, no bottle heater, lesser spec pulsoids and basic controller ). But it for some reason has triple the effect on the road.

Bottle is mounted correct way round:



And nitrous delivery lines are far shorter than mine, maybe upto a 3rd shorter:





Despite having the braided line and no bottle heater this system suffers almost zero delay in activation, unlike my very poorly system.

Thanks for any help or advice you can give to point me in the right direction, i have nearly over £2000 on parts and fitting for this nitrous setup and i just dont think the minor/zero gains it gives is justifying itself.

Both cars are running 50bhp shots of nitrous, exact numbers i dont know. I will check asap.

Its also worth noting that naturally my car has been dyno'd at 215bhp and the other at 170bhp and off nitrous the cars are pretty much even. On nitrous my car gets left in the dust.

I didnt fit the system, my local nitrous specialist garage did, who is recommended by WON for South East installations.

My car now currently runs the x-10 pulsoids with nitrous supplying a blue unit and fuel to a red unit, As instructed by WON.

Do the pulsoids differ internally for fuel/nitrous?

Yes, but its ok as the configuration you quote above is correct.
"Although our fuel and nitrous Pulsoids 'look' the same (apart from colour), there are in actual fact 4 internal differences (in mechanical, magnetic and electric parts), that 'we' developed to make the two Pulsoids more 'matched' in their response rates than any other solenoids"
I expect Trev will assist as soon as he spots this, but what jets are you running, as I'm sure he'll ask too?

As requested, the Jets im running:

Fuel = 40
Nitrous = 100

Im uploading some more in depth pictures now that i took of the system, and some various controller settings i dont understand lol.

I'm suspecting controller settings, I'm sure we can resolve this

Sounds like its possibly running rich?

Why dont you pull the lines off the pulsoids or crossfire and do a quick flow check Ben ??
Or even better flow the fuel test through the crossfire itself.

1. Nitrous bottle off and line depressurised, but with engine lidling. Activate the throttle switch with the fuel line into a small bottle or similar. You should see a healthy even flow of petrol.

2. Other way round this time. Engine not running but have ths system armed. Take the line out of the nitrous pulsoid and keep clear. hopefully you can rig it so the fuel pump is not running. Then activate to see what the gas flow looks like.

If you want to do it properly you can do 10 seconds at full output on the fuel and then measure how much comes out. You should see around 40-50 ml of pretrol assumming your fuel pressure is around 3 bar.

You can do the same with the nitrous for a 5 second test by weighing the bottle before and after. This will tell you how much gas you flowed for the 50hp nitrous jetting.

Perry

Right heres the controller settings, i tried to get as many as i could find. If i've missed any when i get informed i'll retake the pics.

For the most of these settings i havent adjusted them at all, some were adjusted by the Nos Installer and the others are factory settings. All i've adjusted is the basics like start power, build time, gear delays, rpm switch etc.

More detailed pics of the install:

Angle of bottle outlet, the right hand side of the picture being the rear of the car.



Bottle connections:









Fuel take off:





Angle of injector in inlet:





And finally, delivery line passing over exhaust manifold:







I dont think i could supply any more information if i tried lol, Any help or advice is greatly appreciated as always. Thank you.

Ben.

I'M a newbie to nitrous but hope you get this sorted. Looks like an awesome set up

Improving in gear acceleration by 3 secs is pretty impressive though. When it's all sorted it's going to be an animal.

10 down to 7 with a very aggressive controller map i think personally isnt good enough.

Thanks anyway, hope to sort it before august as thats when the next drag day is....

I would just check through the system as Perry suggested

1. remove outlet pipes from pulsoids and then test flow of N2O & Fuel

2, down size jets reconnect pipes and try a static test

3, if 1 & 2 ok then its going to be controller settings there is a flow chart in the instructions link

Austin

I'm sure it will be mate.

Will keep an eye on this as that's a very similar set up to what I will be getting soon.

Good luck with it.

The only thing i can say ben is the bottle outlet should be at 5 oclock as you look at the top of the bottle..i have mine fixed transversed like yours...just watch this and you will see what i mean..http://www.youtube.com/watch?v=WDWW4ejVXzc

oh forgot to say .. when i had the 4 way oulet from my bottle trev said there was a much better way then that ...so when he sees it he may advise, these little things may all add up...

I know nothing aobut your controller!!
What does "gear reset 4 seconds" mean ?

Sorry to hear of the problem but we'll find the solution.

Is the nitrous supply pipe running over the top of the exhaust manifold without the pipe having any protection against the heat?

Have you checked the spark strength for each cylinder?

Is the exhaust stock?

Is the exhaust stock on your girls car?

Thanks for all replies.

Gear reset is the time it takes when im off nitrous activation for it to revert back to gear 1 and its settings.

Both exhausts are aftermarket, both having 4-2-1 manifolds, no cat and a single backbox, both having dual outlets.

supply line is heat protected and goes over the top of the manifold for about 10cm in length and 20cm above the manifold.

And the spark strength!?!?!?

I'm not sure whether it makes any difference but do you have the fuel & nitrous lines in the correct position on the crossfire (regarding which one is closer to the engine/throttle body) as I know it says to put the fuel one in front i.e. in the position adjacent to the direction markers on the crossfire, with the nitrous one behind. (Damn...just checked picture and yes, they are correct...doh!!!)

Also looking at the crossfire it looks like it needs rotating more so it's at around 15 degrees off line.

As I said, I'm not sure how much this affects the perfomance if any but I'm guessing the information wouldn't be in the manual if they had no relevance.

On to the performance, it does sound with the power you have as standard that you should be getting more benefit on nitrous.

As an example to give you 'some' sort of idea, I run a 1.7 Puma which is only 123bhp standard, with 100/50 jets (I believe I'm running very rich at the moment) I get the following reduction in acceleration times when using nos:-
30-70 in 3rd gear - 2 seconds (10.44/8.37 running 40/20 jets)
60-80 in 5th gear - 4.7 seconds (11.81/7.07)
80-100 in 5th gear - 3.6 seconds (12.78/9.18)
I did the latter 2 tests in 5th rather than 4th so that the rpm was lower as previous tests seem to indicate that it wasn't worth having the nitrous at high rpm (as the 3rd gear test shows as it was near the redline at 70 - haven't done that test on 100/50 jets yet). Getting it in at lower rpm was giving the greatest benefit by far meaning lower gear change rpm's which I much prefer. All tests were done at 20% start with a 3 second ramp up time.

Hopefully some help to you (probably not but thought I'd write it anyway)...lol.

Hope you get it sorted

To add: Been out and done a 56-85 run in 4th on my car to give a comparison (despite cars being totally different...lol). I'm guessing yours must be a lot higher geared or you have 6 gears, mine only having the 5. Anyway, it did it strangely enough in 7 seconds on the nitrous and was from 3500-5500rpm, this was 20% to 100% with a 3 second build time.

A thought here:- It seems weird that mine is as quick as yours i.e. 7 seconds, for 2 reasons, 1) despite my lower gearing and 2) on gas the power of mine being a theoretical 173 (123+50 N2O) equals your standard bhp which I can't help thinking means yours isn't running as fast as it should OFF the gas.....I'm confused unless of course mine is running an insane amount of extra torque on the gas.

As Trevor says, I'd check the spark strength but as seen in another members car, I'd also check the nitrous pipe route from the bottle to make sure there are no kinks/extreme bends restricting the flow.

And another thought which may or may not be applicable to your car, I'm assuming yours is setup so the gas only comes in at WOT (Stupid question I know) as the ECU should then not be interfering with the fuelling/ignition etc but if it's set before WOT it may indeed be interfering as is the case with mine when I do a static test i.e. it doesn't do it properly...lol.

Thanks for all the advice from members

okay first off, noswizard the spark strength hasn't been tested but all plugs record good colouring, ecu does not detect misfire nor does the lambda sensor detect any unburnt fuel or a excessively rich/lean mixture on nitrous.

The ignition system is a direct coil type, that being the type with pencil cos over each plug, wasted spark setup as standard with standard plugs ( although they seethe same plugs as used in the turbo megane so should be more than cool enough ).

The car runs fine off nitrous, keeping on par with other similar powered vehicles. And yes it does have 6 gears for those enquiring.

I will move the bottle to the 5 o'clock position for safe measures. Regarding the line I replaced the braided line with the nylon line myself so know it isn't kinked, I will however check in the alkward places like the pedal area where it passes behind them securely.

Thanks.

Edit: on a side note how do you go about testing the spark strength on a modern ecu controlled car l. And regarding an earlier question, my car has a small primary cat at the end of the manifold where as the other car doesn't. This is a 300 cell type I believe, approx 1/3rd the size of a normal cat.

Is there much gain to be had from a straight through exhaust with nos?

That must the culprit. That catalytic converter chokes the engine when on the gas.
I have a decatted racemanifold on my car and it`s a night and day difference on and off the gas.
See if your can get a decat pipe. B.T.W. What diameter exhaust do you have?

One other thing that can have an adverse effect is the ecu. These modernday ecu`s have all kind of safety measures to keep the engine from knocking itself to death. But they can be overacting.
On my car for instance there is an active knock control system retarding ignition, but not when the knock sensor detects pre ignition but when it thinks the engine will detonate under certain engine loadings or fuel quality limits.
The detonation sensor is also a very crude one. It doesn`t have filters, so it picks up frequencies everywhere; road irregularities, noise from my race manifold, short ram intake, sharper cams etc. It even shows engine knocks when I accelerate hard in 1st gear because of my strengthened engine mounts.
I can monitor all ignition settings and detonation via my Hondata flashpro management system and I found that I hardly had to retard ignition advance, even when on a 100 bhp nitrous shot. What I did was compensating by adjusting fueling and cam angles.
The stock ignition advance curves were pretty conservative and the ecu had an overzealous tendency to remove ignition advance when it felt like it.
Don`t know if your ecu is chipped but the engine may be removing quite a lot of ignition lead as soon as you turn the gas on. On these engines as soon as you remove ignition timing you tend to loose a large amount of torque. My engine does.
I understood that your F4R 830 engine has a rather high 11.5:1 compression. Perhaps it is possible to have the ecu remapped to make it better suited to nitrous use.