i spoke to wizards of nos a while back, and i asked how they set it up, (eg with WB afr meter, det cans etc etc)


he sed no we just change the jets till it feels best.


is this true?


wots the best AFR with gas (i mean safe/best)

does the ignition need trimmin, or retardin/advancein to get the best of the nos,

as i always hear of cossie havein nos just put on without a remap.


cheers danny

 

PMSL. That sounds good.

Increase the jet size until you hear the Big Ends wanting to turn inside out, then come down one size.......

 

 

it is set up using a static test.this is unique to wizards and does not work on any other system.you are supplied with "rich" jets as standard.on na cars hold revs at 2000rpm,activate nitrous and revs should rise to just below the red line.this is the "perfect" mixture.this does work on some turbo cars but not all.

 

but surely thats not accurate, as there's no load at all.

 

it depends on the car the nos is being fitted to. i think p j motorsport can set up nos on high power cosworths

 

yeah but how?

 

holy shit batman

 

At the end of the day nitrous is simply extra oxygen content so like a forced induction engine it should be mapped for correct AFR and detonation.

When used to achieve a small percentage power increase the cooling effect of nitrous will actually reduce the detonation/pinking limit and as such when increasing power by 10 - 15% with nitrous it usually does not require any ignition retardation. Like wise there can be a small reduction in egt's again meaning that AFR's can remain similar to the non nitrous setup.

However when running in excess of 25% power increase with nitrous the car MUST be mapped correctly for both fueling and ignition requirements. I'm not prepared to give figures though as thats part of my trade that you pay for!!

 

cheers Karl.


i'm not lookin at nos myself, but was just thinkin wot if,
as never believed the car didn't need a remap.

 

I've run Nitrous on a 1.4 Focus, 1.6 and now my Focus RS engine...all in the same car. Its best you take it to be installed by a pro unless u know what ur doing.

But judging by the car u drive, I don't think it'll be much of a chore for ya! LOL

 

i think i nearly just pissed myself

 

Static test that dangerous described is an excellent way of determining the correct jet ratios, but doesnt very well work on cars with a lamda sensor as if they are in closed loop mode the eco tries to compensate for any inaccuracy in the nitrous jetting.

Mapping to a lambda/afr value isnt as easy as you might think as the nitrous portion of the intake requires a different AFR value (actually the term AFR then becomes misleading as obviously its not air!) the main reason for this is the lower percentage of nitrogen present which means that propotionally there is a bigger percentage of oxygen in any given number of molecules, and as the reading you get at a wideband is a percentage it doesnt take a genius to see why that throws things out.

The problem you have here then is that the reading you are wanting to arrive it is then a proportion of the air AFR and the nitrous AFR interpolated to a point relative to the % oxygen you are getting from each source, ie the bigger % power you are getting from the nitrous the more it effects the value, and as this changes depending on where in the rev range you are it gets really quite complicated.

Then you have other factors like the bottle temperature drops during a run which means that you need to lean the mixture off the longer you are on gas even at the same point in the rev range.

So if you were on a hill at 4000rpm and at full throttle and on nitrous the hill was so steep it held you at 4000rpm without accelerating it would mean that you would then have to lean it out over time even though you were at the same load site in your fuel map for the whole time!



With regards to timing, its not quite as simple as the 25% that Karl mentions although thats not a bad ballpark to work to, but its very dependant on the individual engine, ive had increases of almost 100% power from nitrous with NO ignition retard without ever introducing det.
The worse the intercooler on your car the more nitrous you can run, and (assuming the ECU ACT sensor is upstream of the nitrous) the hotter the external temp the more you can run without timing.

In fact if you are looking for the ultimate power output from an engine you can actually often ADVANCE the ignition safely, even on fairly large % gains.


ITs very dependant on the kit you use of course though and all kits are NOT equal, you did the right thing enquiring at wizards of nos, i would advise you stick to that path if you do decide to go for nitrous

 

PS

When using time based progressive control, it complicates things still further as the amount of nitrous at any given point in the rev range is dependant on what rpm you were doing when you went full throttle.

fun, fun, fun

 

cheers chip.

how do you get around the problems of fuelin changes needed at same loads in the map whilist on the gas?

and would bottle heaters cure the problems with bottle temps?

 

Bottle heaters cure the problem with initial bottle temp but cant overcome the drop in pressure during use when you are on big shots of gas.

I get round the fuelling (as wizards of nos would recomend) by using a wet kit with its own fuel supply and you set it up for the worst case scenario so the rest of the time its too rich, safest way to do it, the thing is with nitrous that the potential gains are SO enormous that its not worth chasing down every last BHP from a given amount of gas, its normally safer to jet it rich and then just go up a jet size if you want more power.
Not the most effiecient use of gas but nice and safe for your engine.

 

cheers again.

 

Very interesting Chip

 

Quickly realised that the Wizards set up instructions were really meant for the 50bhp Nova boys. The supplied Jets made the mixture so rich that it totally swamped any Power gains. I can inject up to a 200bhp shot & no ignition retard is required anywhere under any conditions. It took the best part of a year of trials to get the system giving 100% but it was worth it. I use a Heater before Topspeed runs to raise bottle pressure to over 1000psi.
I wish you luck, but be carefull, incorrectly used Nitrous is an engine Killer.always use a Proggresive Controller or it will end in tears.

 

Very impressive post Chip, truly the PF NOS expert

 

apparently rod ,the nitrous cars in the states are actually going quicker by using

less nitrous than they used to

btw,why do people keep asking what fuelling is needed for different map loads etc ,

thought you should only use gas on WOT?

good post though

puddy

 

I AGREE!!!

 

By different map loads they are reffering to different boost levels and different RPM points, TPS should indeed always be reading 100% or the kit shouldnt be on in the first place.

Dont look at american cars for whats the right way to do nitrous, i could take every single one of the top nitrous cars in the states and show you how to make them quicker without even spending much money on them, they are VERY poorly designed systems that they use, its just that they have been doing it that way for so long that they have got good at making it work.

A friend of mine runs a mid field pro-mod car, running low to mid 6 second quarter mile passes.

He has recently swapped from a traditional american setup to a custom designed UK one.
He is slightly quicker now than he was to start with.
Previously he used to have to replace pistons after most race meetings, now he can run a couple of meetings on the same set of spark plugs, there really is THAT much difference in how damaging the two systems are to the engine and yet still make the same power, and the UK system does it from less nitrous than the yank one too as its making more efficient use of it.

Expect in the next few years to see ALL the top promod guys running completely different setups to the ones they run currently.

 

What fuel pressure do you run Rod, or is that a secret that mark wouldnt want disclosing?
Cause assuming its standard cossie pressue the supplied jets should be only a touch rich when running 1000psi pressure in the bottle.

Obviously though if you are running higher fuel pressure it would make them horribly rich.

 

Chip - what do the guys in the states use then that's so wrong?

Just interested...........

 

Rich, there are so many ways they are wrong mate.

They dont control the flow of it properly, they hit it in stages instead of progressively.

They dont pay any attention at all to flow dynamics along the pipe, changing pipe sizes all over the shop, the solenoids they run arent matched to open and shut at the same rates for the fuel and nitrous which leads to lean conditions, the piston designs they use are wrong (cant really disclose details of that in an open forum) they locate the solenoids too far away from the injectors meaning that they exagerate lean conditions as nitrous travels quicker than fuel.

And thats really just scratching the surface with stuff i can talk about publicly, i could go on and on about it mate there are SO many things they do wrong, but my friend wouldnt be too happy if i went into much detail so im not going to, as there is massive money involved in racing at that level so sometimes a little secrecy is useful.

Some are better than others of course, but most of them share all those problems.

Several of his competitors, even some of the guys beating him still due to the amount of extra money in the rest of their cars (he has a 50K a year budget and some of them have 10 times or more that money) are currently trying to convert to the same system but wizards of nos wont currently supply them as they have signed an exclusive deal with Johnny that hasnt yet expired, so for now its only him running it.
As soon as one of the front runners swaps over though everyone will obviously notice the difference and will follow suit, hence what i was saying that you can expect in a few years to see them all running completely different systems to they do now.

 

Cool - always wondered about that stuff, as I've only ever seen NOS and Zex stuff up close - I gather you're not a fan of them then

 

Im a fantastic fan of them in any car ive got to compete against

 

This is my mate Johnny's car:





This is his manifold with the nitrous solenoids attached directly to it with the jets straight out the back of them so the length of pipework after the solenoid is exactly zero!



Nitrous is put in upstream of the fuel, it mixes better that way and also it guarentees the two arrive at the same time!



This is the built engine:

 

That's a rather sexual looking engine!

 

The new setup he is going to have next year actually works far better but looks less impressive from a nitrous point of view as it only has half the number of solenoids.

His current system is capable of delivering in excess of 3000bhp, but its only used on 1200bhp jets.

Its quicker like that than it was with the previous spec running 1500bhp jets!

 

is he in the low "teens" with that motor yet?

puddy

 

it aint no blower motor puddy or did you mean 7.teens? lol

 

I was joking danny

puddy

 

I know!!! lol

 

although jonny has run 4.22@1/8th which is on for a 6.40@1/4 and I believe this has been with problems. I'll be getting first hand use of the WON kit soon so will be good to see the differents, there are improvements over US kits but you can't take it away from the US kits as they have ran the numbers despite how crap they're said to be.

 

Agreed

puddy

 

Nitrous works so well that even a bad application of it pulls the numbers.

Fitting a US kit makes your car faster than not fitting a kit, i wouldnt ever dispute that, so they definately work, but they are very old technology even at the top level, and although its a way to get nitrous into your engine its not the best way to do so.

Promod is an unusual situation though, you are just dumping the gas in constantly as such enormous quantitites and for such a short period of time (6 seconds isnt long by anyones standards for an engine to need to last) that it doesnt highlight the problems with the kit as well as lesser formulas do.

Sadly johnny has never had the budget to compete, he has been running on stuff like hand-me-down clutches and things like that, so its not really the best car possible to be demoing the kit on, but on the other hand if he can pull the numbers despite other issues then i guess thats far more proof (him leapfrogging the competition) than the guys at the front using the kit and staying at the front.

I believe that the new "smoothy" system on his car WILL pull those numbers, but as you say, until it does, the US kits are still winning.

 

6 seconds is a very long time when an engine is tuned to its limit, I know your clued up with nitrous but you should apprieciate that the extreme cylinder pressures do great damage if the DUMPING of nitrous is done incorrectly, not to mention the strian on the crank shaft with the heat and weight of the clutch assembly, I have faith in trevors kit hence the reason we are trying it on steve's car which is already a proven car as we have 4 championship wins and a world title with it, ALL with a US kit. I truelly hope trevors kit will be what it takes for us to be the first fully street legal car running on unleaded, street tyres tax and MOT in the 7's.

What motor does jonny run?