NITROUS OXIDE ( nos / n2o ) advice forum

Besides a road test at wot and plug check is there anything else i should know that would benefit me in finding the right ratio?
My initial road test was done with a 20 fuel jet and a 50 nitrous which gave a noticeable although not earth shattering difference , the car definately felt like it had an extra set of lungs .
The motor doesnt sound rich when coming off the gas and runs great so is there a chance that i may have got lucky with the jets that highpower supplied ?
Incidentally, when doing a static check the revs only rose 6oo rpm , (then i remembered i hadn,t undone the bottle lol . With the gas on the revs only came up a few hundred rpm more .
Damn i wish doncaster was closer than 5 hours away !!

Well on the surface it sounds a bit rich, but where you are you could pop along to a rooling road and setup the raito with the help of dynamic loading and a wideband lamda sensor.

I am sure you could make it to Owen Dev, PowerStation , Thor or Interpro easily.

Then you know you are spot on.

Thanks for the reply mate , but what is it that makes you think i,m running a bit rich ?

Well the revs should climb and hold somewhere near the redline, revs not increasing could be a rich setup.

Maybe it could be that gas instead of liquid is being injected, heat protection of the pipes and shorts routes are best.

I am sure Trev, will have other definate answers.

Thats what i thought should happen to (especially with a 50nitrous and 20 fuel jet , which i,d imagine is fairly lean). But as i now understand ,the static test doesn,t always yield good results on certain cars
and if this is the case the vehicle should be roadtested to guage any improvement .

Very true.

I would still say for the cost of an hour on the roolers, its nice piece of mind.

The first bthing all my customers need to keep in mind is that they will never be too lean on the starter jets (unless one of my team makes a mistake - which is very unlikely).

Before commenting on this specific case I need to know what the vehicle spec is?

Regards

Specs are 1987 toyota supra , 3litre twin cam straight six, with an induction kit /headers 1 grade cooler plugs (copper), new leads cap , rotor, and the air flow meter has been mildly tweaked to increase fueling as these cars run on fresh air and i didnt want to introduce nitrous while the engine was running lean across its rev range from std .

How have you tweaked the fuelling ?

Remember Nitrous super cools in inlet charge.

By doing this http://www.tscperformance.com/supra/afmtune/afmtune.htm
It relly made a diffrence to all round tourque (only had to adjust it 2 clicks on the gear as well)
N/a supras run fithy rich on start up and on fresh air when warm

Got to say what a right bodge job

If the mapping is so bad on good quailty UK fuel, then the best way to fix it is a piggyback ecu.

At a guess you are overfuelling the car to see small gains in power, this over fueling is made worse with the direct fuel injection with the crossfire nozzle.

It certainly the better way to be, lean is a big no no

It may look like a bodge , but it really works well .
The plugs are now the right color / the engine pulls stronger and it idles very nicely (even with the colder plugs )
As with any engine mod the proof is in the driving and not always found on a dyno slip .

You've got some kind of problem as your car should respond well to a static test.

Give the office a call and speak to Ant telling him the results of your tests. Have you got a pic of your bottle mounting and your solenoid location?

Regards

i,ll post them up asap Trev

dont forget trev this is the one with the really long inlet that starts on the offside of the engine,then goes over the top of the engine where the butterfly is and then curves back round into the engine on the nearside.
could this long inlet cause the fuel and nitrous to not reach the engine very well on the static but be ok on full throttle?
bryan

I'll reserve judgement till I see the pics.

Regards

Spoke to Ryan today and he,s happy that the initial jetting was ok , and now its time to go to 50hp .
Heres a few pics of the install any way .

After struggling to find the right spot for the pulsoids i found a nice mounting place behind the coooling fan . I had to make a compromise between injector supply length and heat reduction

Heres where i put the bottle

All thats left to do now is fit the minimax and find some decent heat insulation for the injector supply pipes/intake/headers to tidy that area up

This is a very old system so I suspect the filter is blocked. Before fitting bigger jets I'd fit a new filter as I'm confident the static should work on this vehicle which indicates to me that you're not getting the full amount of nitrous you should be getting. Assuming the bottle is full of LIQUID and as you have the bottle mounted correctly, that only leaves excess heat in the supply pipe or a restricted filter.

By the way if you want to go above 50 bhp you'll need a 5mm pipe upgrade.

Regards

Thanks for the advice Trev, the nitrous filter is pure white and the nitrous supply line has been rerouted down the cool side of the inner wing.
So that really just leaves the question of what and how much is in the bottle (incidentally the bottle is the oldest part of the system).
I,ll leave things as they are on the 50 shot for know and see how it goes
Then i,ll fit the 5 mm pipe