Author Topic: NOS fuel install...  (Read 4162 times)

Offline SaltandPepper

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NOS fuel install...
« on: January 24, 2019, 01:40:04 PM »
OK, need some advice here. I bought a single stage cross bar nitrous kit and am currently installing. Looking at plumbing the fuel solenoid. I have a 10an main fuel feed coming off of my fuel pump to the fuel pressure regulator that then splits it into duel 6an feed lines to my 750cfm 4150 carb. The directions specifically state that the fuel solenoid for the NOS must have its own separate regulator. However, in the limited space I have it would require quite a bit of plumbing to reduce the 10an down to 4an that connects to the solenoid and I would have to plumb a T valve into my 10an line. I also have a fuel pressure safety switch that will disable the NOS at 5lbs. I usually run my regulator at 8lbs. I understand what the directions state. It would be a heck of a lot easier and compact for me to plumb that solenoid from one of my 6an lines and use the regulator that I have for the carb than to cut into that 10 and add a separate regulator. Since I have the pressure safety switch is a separate regulator honestly needed? In short, could I honestly get away with this or should I go with a separate regulator?

Offline BK

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Re: NOS fuel install...
« Reply #1 on: January 24, 2019, 02:15:30 PM »
Assuming you have a T where the 10 reduces to the 2 6s.
How about drilling and tapping the side of the T for your -4 line.

Offline SaltandPepper

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Re: NOS fuel install...
« Reply #2 on: January 24, 2019, 02:53:07 PM »
Good thought BK but the regulator is actually the T....the 10 runs into the bottom of it and the duel 6s come off of each side

Offline BK

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Re: NOS fuel install...
« Reply #3 on: January 24, 2019, 03:40:51 PM »
Google -10 gauge fitting

Offline noslin

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Re: NOS fuel install...
« Reply #4 on: January 24, 2019, 04:49:05 PM »
unless you have a huge pump i would run two pumps and also run high psi on fuel side.  purpose for high psi (say 30-40) is the margin is less if your off say 1lb psi.  if your going to run 5psi and your off 1psi, thats 20% of the tune where as how many psi do you need to drop at 30 to be off 20%.  also have to account for volume of fuel on hand if one pump which the reason why you run -10. 

Y from the pump using -10 'Y' then to both regulators.  if your going to run the holley reg like a lot of guys do then thats 3/8" pipe i believe.  one side -10 to 3/8 to reg and other side 3/8 to  -4 which is made.  idk if you plan on splitting after the carb reg but i dont feel it would be a good idea.  you T after the reg then is your carb getting the psi it needs and also the volume of fuel it needs?   just look at psi the carb is actually seeing when you turn the kit on.

not sure how your going to split the system but thought i would interject a little bit. the tune is critical when you start messing with power adders.

the other thing too is ignition and battery voltage.  lot of guys will build a big ole 540 lets say and then run a programmable 6 on it with the a blaster coil.  so, make sure you at least have good ignitions like a msd 7 w/ the 2amp coil they sell or sim.  further batt voltage will have an affect on tune too.  think again about the 5psi base fuel.  what happens if the voltage drops a little bit and battery is seeing another amp or two because of demand?

Dean

Offline Roger

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Re: NOS fuel install...
« Reply #5 on: January 24, 2019, 07:00:10 PM »
Sounds like you have something similar to the photo. I used a #6 AN gauge adapter with a 1/4" pipe thread for a gauge on one side and on the other side the same fitting will be used for the RacePak fuel pressure sensor. Instead of the sensor, put a fitting in and attach your 4 AN line.

Offline dusterdave173

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Re: NOS fuel install...
« Reply #6 on: January 26, 2019, 01:03:22 PM »
Perfect GROUNDS are a must! make sure that all wiring is soldiered and shrink wrapped--grounds must be perfect and reliable or you will have issues
I have always had a fascination with fast cars at the expense of more normal character development

Offline noslin

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Re: NOS fuel install...
« Reply #7 on: January 26, 2019, 04:29:17 PM »
Perfect GROUNDS are a must! make sure that all wiring is soldiered and shrink wrapped--grounds must be perfect and reliable or you will have issues

100% what Duster Dave said, people overlook this and its the crux of a lot of issues people will have.  also, do not ground to the chassis.. you need floating grounds (and power) directly from the battery.

Offline dusterdave173

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Re: NOS fuel install...
« Reply #8 on: January 27, 2019, 12:33:19 PM »
Yes many installs get low voltage To the solenoid so use correct gauge wire and TEST voltage at the solenoids when applied
I have always had a fascination with fast cars at the expense of more normal character development

Offline SaltandPepper

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Re: NOS fuel install...
« Reply #9 on: January 27, 2019, 04:22:53 PM »
Thanks fellas, getting ready to run wire and plumb this week, good advice. I ordered another regulator and will run my fuel off the main line....will post pics when done.