Nitrous set up and prep

[Brooks James]

I’m getting ready to set up my plate nitrous system 50/100/150 hp
Here’s the plan:

1 correct bottle angle
2 non projected spark plugs a heat range colder than stock file rough edges smooth
3 carefully check timing
4 retard timing 2 degrees for every 50 hp of gas
5. Make a 1/4 mile pass stop immediately
To read plugs
6 make adjustments according to how the plugs read more or less nitrous/fuel
7. Install nitrous cutoff if fuel pressure drop
8 installed air/fuel ratio gauges tune to between 12.8 to 13.2 to 1 at WOT
10 install wide open throttle switch for nitrous activation

Am I forgetting anything???

 

[DrCharles]

The tunes recommended by the nitrous system manufacturers are WAY too rich...for example, a 150 hp tune from NOS is 63N/71F (5-6 psi fuel pressure). But the late Monte Smith recommended starting at 65N/52F. That's a big difference.

 

[Brooks James]

The tunes recommended by the nitrous system manufacturers are WAY too rich...for example, a 150 hp tune from NOS is 63N/71F (5-6 psi fuel pressure). But the late Monte Smith recommended starting at 65N/52F. That's a big difference


Thanks I’m going for the 100hp setup
Do you have any idea what a good starting point is for the jets or where I might find out

 

[Brooks James]

Thanks I had read that
I had forgotten about the fuel pressure

 

[Biff]

I like to start opposite fuel rich /nitrous lean then go from there

 

[Brooks James]

The tunes recommended by the nitrous system manufacturers are WAY too rich...for example, a 150 hp tune from NOS is 63N/71F (5-6 psi fuel pressure). But the late Monte Smith recommended starting at 65N/52F. That's a big difference.

thanks do you have any idea or know where I can find info on jets for 100 hp set up

 

[Biff]

thanks do you have any idea or know where I can find info on jets for 100 hp set up

Depending on you system brand that info should be on there site ?

 

[Brooks James]

Depending on you system brand that info should be on there site ?

I was trying to take Dr Charles’s advice
On starting with different jets as he said that Monty smith said to start with different jets as that commonly come set up rich which means to me that if the factory supplied jets are too rich for a 150 setup then they will probably be too rich for the recommended 100hp jets

 

[DrCharles]

I'm no expert... But I do a lot of reading. Eventually you can pick out the useful wheat from the chaff...

I recommend starting with this (now 10 year old) thread on YB:
Timing Tuning vs Jet Tuning

 

[CFD244]

Is the bottle going to be mounted in the trunk? Right above the 3 foot flames?

 

[Brooks James]

I'm no expert... But I do a lot of reading. Eventually you can pick out the useful wheat from the chaff...

I recommend starting with this (now 10 year old) thread on YB:
Timing Tuning vs Jet Tuning

Thanks

 

[Brooks James]

Is the bottle going to be mounted in the trunk? Right above the 3 foot flames?

From what I’ve read nitrous in the bottle is not flammable it’s when it’s introduced into the engine that it’s flammable I’ve been wrong before

 

[Biff]

Nitrous is not flammable but it needs to be hard line vented out side the car see NHRA rule book .

 

[SLOPAR72]

Nitrous is not flammable but it needs to be hard line vented out side the car see NHRA rule book .

Pop off valve.....

JW

 

[Brooks James]

Pop off valve.....

JW

What do you mean “hard line vented”

 

[SLOPAR72]

Thanks

A 150 is not a huge increment in power. Oh it's gonna be good but not at a level where you need to have a setup like a Top Sportsman car. Opinions will vary on that.

If you want to keep everything in check get a Bottle heater with a Pressure gauge. Alot can change from just 25lbs. of pressure variation. I wouldn't put the effort into the EGT myself. AFR is fine. Make sure you have additional Ring gap also although a 150 shot tuned properly should "used loosely" be OK without doing that.

And yes Yellow Bullet is a good source for your project....

JW

 

[Brooks James]

What do you mean “hard line vented” and pop off valve

 

[SLOPAR72]

What do you mean “hard line vented”

If you bottle pressure exceeds a certain pressure basically it will exit the Gas from inside the car. I have been in a NOS car that had a leak. It will catch you off guard and quick like. And I sure wouldn't want to be around a Bottle that's blown it top lol.....

Now the other reality is if the Bottle explodes. One in a million. But honestly if it did you won't be around to tell us about it. She go boom and it goes bad....

JW

 

[Brooks James]

A 150 is not a huge increment in power. Oh it's gonna be good but not at a level where you need to have a setup like a Top Sportsman car. Opinions will vary on that.

If you want to keep everything in check get a Bottle heater with a Pressure gauge. Alot can change from just 25lbs. of pressure variation. I wouldn't put the effort into the EGT myself. AFR is fine. Make sure you have additional Ring gap also although a 150 shot tuned properly should "used loosely" be OK without doing that.

And yes Yellow Bullet is a good source for your project....

JW

I found the setup you are talking only a few bucks for major safety factor
I’m guessing hard line would be hard steel lines instead of braided stainless

 

[SLOPAR72]

I found the setup you are talking only a few bucks for major safety factor
I’m guessing hard line would be hard steel lines instead of braided stainless

definitely not braided. Small cost for what it does when you need it.

JW

 

[Biff]

There is a valve between the on off valve and gage

 

[j par]

Nitrous plumbing A1A...??..
I've covered all this^^^^
Most factory settings are rich and that's the way I'm going to try mine first...
I have every safety device possible and play in mine..
Activation switch, full throttle switch, window switch, low pressure switch, MSD start retard... Amongst other things like a full standalone fuel system with 110 Sunoco.. of course a temperature controlled heat blanket keeping the bottle at a perfect 93 degrees for a perfect
950 lb... On every bottle there is the exit tube which runs to your nitrous and on the opposite is a blow off plate that will pop at 1,500 lb.. if the bottle is in the cab of the car like mine you need a hard-line coming off of that exiting the car in case that plate burst and it doesn't fill up your car with nitrous...

 

[33IMP]

The announcer at my local track says we should plumb the nitrous purge into the car, make the driver happy.

Somehow, i don't think it will pass tech.

 

[DrCharles]

The announcer at my local track says we should plumb the nitrous purge into the car, make the driver happy.

Somehow, i don't think it will pass tech.

The sulfur dioxide added as an irritant won't do the driver's lungs any good, either.

Why set it up to "factory" rich? You wouldn't jet your carb for a 9:1 or 10:1 AFR, which is the equivalent of what the nitrous system companies are recommending. All that does is blacken plugs and make less power.

 

[Brooks James]

The announcer at my local track says we should plumb the nitrous purge into the car, make the driver happy.

Somehow, i don't think it will pass tech.

I’m planning on if it looks like the guy next to me at the light looks like he wants to race I will purge the system and direct the nozzle spray onto his wind shield. Yes I am irreverent