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-   -   How to Modify / Tune your car - 2 - Nitrous (https://www.team-bhp.com/forum/technical-stuff/55361-how-modify-tune-your-car-2-nitrous.html)

Well GTO had put up a post on Modding and Tuning your car where he talked about modding the car in stages and what could be done and what not. I thought that I could add to that bit in this post where I would primarily focus on detailing the forced induction aspect of things before anything else. This thread will focus on nitrous, there is another thread for superchargers here.

There are enough and more options out there for going fast but what exactly is right for you and when is the biggest question. the next question is usually how far can you go and what does it take, I shall take these up in a few posts gradually in this thread and share as much information as I can. Shall be starting with Nitrous as the first option

Nitrous:

One of the quickest approach to a fast car and a quicker approach to a blown(no reference to turbo's or superchargers here) car if not done right.

Nitrous is just packaged air to send more oxygen into your combustion chambers in a chemically stable form so that it does not explode outside your cylinders. More fuel and more air can help get more horsepower also lead to detonation (which is capable of destroying your engine)

So what does it take to run the right choice of a nitrous system on your vehicle?

Check the key parameters:

Compression Ratio: 8:1 - 10:1 (Have not brought cc into consideration yet and prices are only indicative without import)

• Lower the compression ratio more the effects of nitrous are obvious on a stock car
• Lower the compression ratio higher the nitrous shot (Shot: A measure of nitrous that is injected into an engine)
• Lower compression engines tend to handle dry shots(without additional fuel being injected) much better
• Higher the compression the lower the limit of nitrous used theoretically

Fine if that is the base minimum then what kind of nitrous system should I use:

Types of nitrous systems

• Single Nozzle - Dry Shot
  - Can be suitable to any type of car
  - Easier to fix and run
  - Just about enough bang for the buck
  - Prices typically start at $ 350
  - Can handle 35 - 150 shot (rough translation into HP figures too)
  - Typically comes with multiple jets
  
• Single Nozzle - Wet Shot
  - Can be suitable to any type of car
  - Needs additional plumbing for the fuel line
  - Fuel Pressure Regulator reccomended
  - Prices typically start at $ 450
  - Can handle 50 - 150 shot (rough translation into HP figures too)
  - Typically comes with multiple jets
  - Once in a while race
  - Do not try above 50hp on your own on a 1.5 ltr on and definitely not such a high shot on a lower capacity engine
  
• Plate Type - Dry and Wet
  - Suitable to carburetted cars
  - Needs additional plumbing for the fuel line
  - Prices typically start at $ 350
  - Can handle 50 - 300 shot (rough translation into HP figures too)
  - Typically comes with multiple jets
  - Race scenario only recommended
  - Needs the hand of a good tuner
  
• Direct Port -Wet Shot
  - Suitable to Fuel Injected cars
  - Needs additional plumbing for the fuel line
  - Fuel Pressure Regulator reccomended
  - Prices typically start at $ 400
  - Can handle 50 - 300 shot (rough translation into HP figures too)
  - Typically comes with multiple jets
  
• Direct Port - Progressive Controllers
  - If you race quite often
  - Needs a good tuner
  - Might need multiple sets of jets based on the controller used
  - Costs start to skyrocket

Let me now start with the key points that can help destroy your engine before going further

• Factory plugs - trust me they will blow out before you release that nitrous button
• RPM Trigger / WOT Trigger: Fire nitrous on a low revving engine on partial throttle and you are sure to blow it to heaven come
• Lean fuel mixtures: Nitrous use requires a lot more additional fuel else the knock of death is for sure
• Restrictive exhausts: Overheat your valves
• Ignition Timing: Needs to be retarted for nitrous use and not advanced
• NOS Bottles: would not blow your engine apart but your car instead if you do not use the forged aluminum bottles CO2 bottles are not direct replacements. It makes me jittery when people try to run NOS systems with cast iron bottles and then try to regulate heat by pouring water on it have seen a guy blow to smithereens while filling in helium in a co2 bottle, stay away

What are the mods that will benefit my car for nitrous use

• Better intakes and exhaust
• Plugs with short ground straps
• Race Cams
• Porting and Polishing
• Fuel pump upgrade
• Additional Fuel Pump
• Forged parts - Pistons, Con Rods, Crank
• Aftermarket ignition controller especially for distributorless cars
• or a Good ECU - piggy back or stand alone
• A good clutch and drive train to transfer the power
• good tyres to grip and not spin out (look who's talkingclap: )
• A good tuner who knows what he/she is doing

Ok now you know the types of Nitrous systems and the risks out there, BUT how do I jet them???

Please be careful from this point on and I would never reccomend that you do this on your own

• Jetting a nitrous system and fuelling is best left to the pro's as it depends on too many factors to list out here
• Jetting can never be copied from one car to another as it varies as per the mods / fuel / fuel pressure / ignition system / strength of the engine etc
• So go to your tuner and have him do it :)

I know this post may not have answered all your questions and I may not be able to do so in one go so I am taking the liberty to point you to some good material here

Have fun and be careful. Do not use nitrous on the street and be responsible drivers.

How about providing a link to an online calculator or a pdf file to determine the jet sizes to be used for NOS applications? It would help customers check if the choice made by tuners is correct or not and for those who want to do DIY.

I always wanted to know intricate details about how a NOS sytem works and is installed and its types. Thanks Keshav for shairing the details.

That was really detailed. Thank you for throwing the light.

Liked the NOS bottle part. We are quick enough to find indegenous solutions right?
Since this might be illegal on street, and looking at the list of mods required, i think should wait for the next mod option !.

Very well put up Keshav. add to that,
A nitrous pressure gauge is what i highly recommend to install, you must run Nos using correct pressure or else it will effect the target AFR's greatly & chances of engine blow up increases.

Thanks for the info.

I have heard that NOS bottles are used only for drags?
As bottle will soon get empty. If not how many kms can one drive with MAX amount of NOS filled in?

Has anyone tried NOS on diesel engines in india? If yes, is it reliable?
Can i drive for around 200kms with it?

@brbraj - Life of a NOS bottle depends on how much and how often you use it. In all NOS builds there is a button which when pressed opens a valve which allows NOS to enter your car's engine. If you don't press the button there is no NOS going into the engine and the bottle will last forever (at least theoretically).

Edit: Nice informative thread Psycho.

How many kms can we drive with NOS ON?

keeping these conditions in mind
- lets say its a mild NOS injection, say putting around 30-50bhp more
(I have read some articles which says 'increase 50-150bhp with NOS injection'.)
- And keeping NOS on till its empty.

Depends on the shot/jetting that has been used. A 10lb tank is good for about 5 good runs on the drag strip at 85 shot so it would last about 2 minutes tops and the effectiveness starts dropping as the cylinder pressure reduces. It works best at about 900PSI.

As for a diesel I have personally never tried it out but it could be good for about 25-30 shot assuming your car

Rajiv, its like your ordinary cooking gas cylinder. Its longetivity depends on your usage which varies from person to person. Ideally if you were to do a 1/4 mile with say a 30 shot it should last you for around 8-10 runs.

A few things to remember:
1. Its hazardous to keep nitrous button on unless you are at WOT (wide open throttle) as already mentioned, so at low revvs you will end up blowing the engine.
2. Engine might not be able to sustain such prolonged durations of nitrous injection (when you intend to empty one whole bottle at one shot).
3. I doubt you will get such roads to empty a whole bottle with the kind of shots you are planning to run.

:Shockked:

So it seems that not many people have tried NOS for diesel engines in india.

Thanks for the info keshav & rahul.

900 psi is just the bottle pressure at which NOS operates at its best. I doubt ANYONE has tried running NOS on diesels in India yet.

Isnt propane better for diesels? rather than NOS? It works on a different principle, but if done right, can provide good gains in power and/or mileage.
Would be nice to have more info on that.

@psycho- can we also discuss methanol/water injection in FI cars please?
Thanks for the interesting thread

Thanks a lot psycho,excellent thread.

I haven't got one thing though,why can't we run a 25-30 shot on street,firing at WOT.