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19,790 Posts
Discussion Starter #1
a nitrous work sheet
Just one place to put all my thoughts, solutions and working problems down in writing
in public

So here goes

Having experienced n20 only in other peoples cars, [old, heavy metal, with at least a 150 shot, most were 200 shots and above. all 10sec cars ,capable of being street driven, but usually towed to the track]
I have no idea of what a 35-75 shot feels like

So some of this prep and worry may be unnecessary

The biggest initial effect of n2o on me was it hits like a hammer
The smooth application of ever increasing power was present only in the progressive systems; which at the time were maintenance intense [tear down solenoids every 6 runs, now nx lightning solenoids can go a year between servicing]

So in my mind, despite the increased maintenance, only a progressive system would be useful at the track, In order to maintain traction.

A big $$$$ problem, as the better n2o controllers cost more than the kits themselves
With 400-700 dollar price tags

What to do
Companies like dynotune, nos made some 200 buck effective controllers
But I could find no one running a big shot willing to run one
[at paradise in Calhoun, I also noticed none of the alcohol guys run nitrous]
And curiously the n2o guys ran oxygenated race gas

The top controller here is the nx maximizer followed by various nos devices all 4-500 dollars
[I got my new nx mainline kit on craigslist for 200 bucks]

This leads to, no matter, if you choose nos or nx
$400 for controller
$200-750 for used to new deluxe kits
$40- 400 for safety and tuning devices
$150-400 for pressure control [bottle heater to nano]

A simple single nozzle 100 shot capable system
Might be composed as follows
Nx controller
Nx deluxe kit [or like me, the economy kit, with lightning solenoids]
Nx purge kit
Ngk or zeitronix o2 sensor
Nos solenoid bottle closer
With the nx controller set up to monitor afr and alter both n20 and fuel solenoids to maintain it.
Also in lean conditions the nx box can shut down the n20 system AND close the bottle

Pressure control is left unattended, [aside from excess pressure, by venting with purge], due to it’s hot in Georgia
The full effect of the n2o hits after 6 sec.[about 3rd gear] with a soft initial entry

This adds up to almost 1300 bucks, the cost would not change much if you added direct port injection but the complexity would

My main task here is to produce a working, easily usable nitrous system at a reasonable price that my well used motor can tolerate

Doesn’t seem like we are there yet
More thought and input seem reasonable

check slyguys approach for comparison

19,790 Posts
Discussion Starter #2
continuing to try to get a more reasonable cost, i contemplated dropping the o2 sensor
i have read spark plugs for many years and should be able tell a lean condition without the gauge
while this saves between $200-300 it also eliminate the main advantage to the max4, nx, n2o controller

as you may know nitrous pressure declines during a run; if fuel pressure remains constant, we get a safe rich condition developing at the end of the run
in my car however, even with a walbro pump, fuel pressure tends to vary, [esp at wot at the end of a run]
possibly causing a dangerous lean condition
the max 4 uses the afr [delivered by the o2 sensor] to pull ether fuel or n20 to maintain afr.
delivering maxmum power for the present conditions and maintaining safety and efficient running

to discard this safety net i feel that upgrading the fuel system would be a must

if a walbro alone won't do it
then perhaps adding a separate n2o fuel system, to supplement it, would solve the prob [technically]
but to save 300 by spending 400-700 makes no sense

Travis's fuel system with his fuel rail would solve the prob for n2o and the future 4.1 but also is in the 500-600 range.

while both are excellent, almost elegant, solutions, they cost too much to be used in a so called economy set up

theoretically the walbro should handle it, perhaps 2j will dyno the new qr and we will see if the fuel pressure still drops as rpm gets above 6000

[on the vq which ran to 7700 rpm, the walbro was in serious trouble by 7100 rpm]

547 Posts
the biggest problem i see is buying new parts. most of everything is just a part. the noids are a wear item. maybe the progressive is too but most can be picked up used to shave a huge portion of your total off.

19,790 Posts
Discussion Starter #5
thanks pat

as an example
summit lists the mainline kit for 399 bucks, i got one for 250 nib on craigs list
Nitrous Express (NX) ML2000 - Nitrous Express MainLine EFI Nitrous Systems - Overview - SummitRacing.com

i picked up a nos sniper system used but with the bottle heater for 275,from a fellow poster here, summit lists it for 403
Nitrous Oxide Systems (NOS) 07006NOS - NOS Sniper EFI Wet Nitrous Systems - Overview - SummitRacing.com

understand the solenoids will have to be rebuilt or replaced

so for the basic kit and spare bottles this is definitively the way to go

looking for leading edge products like n2o controllers or nano nitrous systems is harder
not many people yet use them
they may be rare items on craigs list

19,790 Posts
Discussion Starter #6
having already cut the o2 gauge, i began to think why not cut the most expensive part for now, the n2o controller.
i can test the initial shot of a progressive system by starting with a straight 30shot and seeing how it launches with just the preplaned 30% of the 90 shot

that cuts the cost total by 700 bucks, now we are getting reasonable
but very gutsy

present idea, to review, cuts all safety measures

no o2 sensor [read plugs]
no fuel pressure safety cut off [answered later]
no window switch [i come off the line at 7000 and rarely fall below 5000 on a dragstrip run]
no safeguard for n2o solenoid failure [eliminate progressive controller, allowing mainline solenoid a greater life span,
then make it the purge solenoid and replace it with a lightning solenoid when the system goes progressive]

system initial start up
wot switch [less than 20 bucks[
main switch [included with basic kit]
and basic kit
still need n20 pressure guage for the bottle
less than 300 dollars to test the idea of being able to use n2o in 1st gear with a high rpm launch

next post dealing with the loss of fuel pressure

19,790 Posts
Discussion Starter #8
fuel supply was my last concern, here my fear was huge
i had already lost a 10 grand motor to an inadequate fuel system

the walbro failed me for two reasons, inadequate fuel in the tank and inadequate voltage to the pump at high rpm and demand

surely the two pump return line system with a surge tank would calm my fears, but at huge cost
picking and choosing carefully
i narrowed it down to upgraded fuel pump wiring and a larger fuel rail diameter, so the rail holds more fuel and acts as a mini surge tank
a quick call to Travis and it was done
new billet fuel rail, tapped for a nitrous fuel take off and a fuel pressure gauge plus an upgraded higher voltage pump wiring kit was ordered

approx 260 for an operating fuel kit that takes care of my fears is a little high but where i am for now

with the addition later of a progressive controller and lightning solenoids the price goes up considerably
but hopefully they will be find-able on craigs list at lower prices

a nano system is also being contemplated

2,289 Posts
hey man. i have been piecing my kit and laying all the wiring out in my head it hasn't made it to paper yet.

what i have been looking into is MegaSquirt III. it has a nitrous controller built in to the tuning system. One of my instructors has MegaSquirt I running on his e85 turbo miata so i was picking his brain about it yesterday. he brought his laptop in the classroom and hooked it up to the flat screen to show us the tuning software. very cool. it also has a 2 step controller built in that can be adjusted

19,790 Posts
Discussion Starter #10
sounds good, i wish i had the skills and understanding to build it
ms III is a proven unit, check darsonisis build, good stuff

i'm using uprev, because 2jr is close by and it's their preferred tuning method
and because i can't build the ms III boxes lol

uprev has a two step but no n20 controller except [hopefully] for a 2nd map with 2* retarded timing

i have a proefi 48 with a 4 stage n20 controller and traction control on order but at present it only fits the vq

having decided on my basic pieces i'm up to the details of assembly, neat wiring and what to do for a switch panel
i think i'm going to mount the tank using the front seat mounts with the passenger seat removed and run the wires and main supply hose out the ecu hole [ some way]

7,388 Posts
Barry have you had a chance to try your aeromotive fuel pump yet?

I think I am going with this one over the Walbro.

19,790 Posts
Discussion Starter #12
Barry have you had a chance to try your aeromotive fuel pump yet?

I think I am going with this one over the Walbro.
according to aermotive, to use that pump, i would also need larger fuel lines [and possibly a return line,[ they told me if i didn't, the pump would over heat and have a short lifespan

call them and ask

i finally went with the walbro, Travis's fuel rail [tapped for a n20 take off for fuel] and upgraded wiring kit and hope that will be adequate for a 90 shot in the qr
i got just the rail

and the wiring kit

19,790 Posts
Discussion Starter #14
Alternate fuel considerations
Seeing the cost of what I chose to ease my fuel concerns, here is an alternative I thought about that works just for nitrous use.
A jegs 1 gal nitrous fuel tank
JEGS Performance Products 15377 JEGS Drag Race Fuel Cells
relay kit
JEGS Performance Products 10564 JEGS Fuel Pump Harness and Relay Kit
$30 approx
holley pump and regulator
Holley 12-802-1 Holley Electric Fuel Pumps
$135 aprox
or jegs pump and reg
JEGS Performance Products 15914 JEGS Street/Performance/Race Electric Fuel Pumps
A fuel filter
JEGS Performance Products 15030 JEGS Billet In-Line Fuel Filters - 2-5/16'' Long, Compact

a short piece of fuel hose and some fittings
JEGS Performance Products 15940 JEGS Mechanical Fuel Pump Fitting Kit
say $50
About 450 installed
or from nx
$420 but you still need hoses and clamps

Advantages of this setup are the use of higher octane leaded race gas [110 octane] and no worry about stock fuel pump inadequacies
Disadvantage is the higher cost and the upgraded fuel delivery system only works with nitrous
In addition special jetting is required to deal with the lower fuel pressure

19,790 Posts
Discussion Starter #17
well, went thru a minor clutch crisis but in the end the CC stage 2 clutch is adequate for a 100 shot
no preload, or clutch slip at the start. lock it up and control wheel spin with the throttle [back pedaling]
the loss of preloading the chassis at the start may cost a tenth but the longer clutch life more than makes up for it [the jwt had the same characteristics]

now with the initial setup decided, the remaining parts listed and about to be ordered

lets talk about taking it to the track

the launch turns out to be very complicated w/o the use of the max 4 progressive controler's clutch switch and rpm window switch capability
the launch on just a wot switch has these obstacles that still need to be overcome

can't use the rev limiter as a two step because wot activates the n2o
back pedaling causes drastic changes in power, leading to bog and spin conditions
can't really floor it till i'm past 60 ft [losing some na power]


19,790 Posts
Discussion Starter #18
back on it as the car becomes available this week
been waiting on a dipstick tube from nissan

after much pondering, i switched systems and partially combined them

NOS and NX use non matching hoses and end fittings but the nx mainline solenoids seem the same as the nos sniper system
as a result i can refit the nx noid as a purge noid in the nos sytem

if you remember i purchased two systems one from nx [mainline] and one from nos [sniper]
in talking with Travis about the fuel rail, i remembered he had the nos system at his place
and that it was a much more complete kit.
used a larger and more easily fitted nozzle
came with a gauge and thermostatically controlled heater
contained all the wiring and switches and relays
and using the nx nitro noid in the purge position in the nos system allowed purgeability
i also had an nx bottle blanket

the combined kits bring us to
a more rigidly mounted nozzle, capable of a 100 shot
the addition of a gauge and bottle heater
and the ability to purge the system
in addition the nos bottle fits the nos bottle opener without modification,
introducing our 1st safety factor, an electronic, solenoid operated, instant shut off valve, at the bottle

19,790 Posts
Discussion Starter #19
Confusion abounds
The car which has been almost ready for weeks
Is ready tonight

Haven driven some lightly modded specs lately
I knew the car would not run with my crowd
the nitrous would have to go in before I visited anybody or any track

So as challenge after good natured challenge rolled in
[even Sammy called me out]
I knew I needed real steel, real fast
This clarified things very quickly,

I had to at least start with the nx kit, that was available here, the nos kit was at Travis's house
Nothing less than a 100 shot could possibly put me on equal footing with the cars around here [read 125-150 in paradise mode]
To deal with the possibly fragile clutch, I had to use a progressive controller
This engine and clutch are dead meat

I have 500 breakin miles to stall and install

So in extreme panic mode
[Its one thing to lose a race, but this is more like not even being in it]

the 100 shot looks this way

FJO controller [built in tps, window and clutch switches]
Nx mainline kit
NOS wiring kit
Summit nitrous gage

Ready for Sammy
But I don’t know about the paradise kiddies
[if it doesn’t break 8s in the 1/8, I won’t be the penguin running from the leopard seals but more like the frozen rat they feed to the big snakes]
Remind me again why I thought less was more

19,790 Posts
Discussion Starter #20
nope, false alarm, maybe wed?

and just as i went to order the fjo controller, i discovered FJO was bought out by Holly [NOS], so its no longer available.
the one fjo makes for nos uses a mini hand held device for programming, i prefer the drag and drop ease of the laptop set up.
still searching for a good low buck controller that has tps and a window switch built in
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