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Life begins @ 30psi....
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Discussion Starter · #1 ·
Alright guys I know many of you have a lot of experience using nitrous and I am still very much on the fence about spraying the Supra.

My question is this....

I would only be running a small wet shot on my car and I am not sure how to handle to fuel setup. My car has about 48psi of static FP and it will see as high as 80psi on big boost. How would I control the fuel being sprayed into nozzle and keep the fuel consistent when the FP pressure jumps so high as the nitrous is coming on.

Thanks,
Bob
 

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FP is always 48!! It will always be 48 psi. Remember that if your FP goes up to 78, then you have 30 psi of boost. The boost works against the fuel trying to come out. 30 psi against and 78 psi of fuel pressure means your static FP is still 48!!
 

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Life begins @ 30psi....
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Discussion Starter · #3 ·
FP is always 48!! It will always be 48 psi. Remember that if your FP goes up to 78, then you have 30 psi of boost. The boost works against the fuel trying to come out. 30 psi against and 78 psi of fuel pressure means your static FP is still 48!!

Hmm I never thought of that way Larry.

Thanks again for the info!!

Bob
 

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Boost Junkie
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There you go. You can email NX directly to figure out which pills to use and richen up your fuel a little while you are spraying.

Steve K.
 

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If you have an aem ems why not run a direct port dry kit and control the fuel through the AEM?
 

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Bob,
What do you want to do? Spray out the hole or the whole pass?

Jason
 

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Life begins @ 30psi....
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Discussion Starter · #7 ·
Bob,
What do you want to do? Spray out the hole or the whole pass?

Jason
Well I would probably want to spray it the whole pass, it will get me moving really well I would think. I will only be using like a 50shot at most and the AEM will control it all. I think a small 50 shot will easily put me into the 9's without much fuss on the slicks. I think a direct port for my meager needs would be over kill and I will not be running a big shot.

Bob
 

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so if I want to calu. the fuel & N2o jets, should I put the base FP 45psi and do not care about the extra psi came from the boost.

thanks
 

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Just an old *******
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How in the hell does 30 psi of boost slow down the 1000 psi of no2 blasting its way out of the same nozzle that has already mixed the fuel and no2?

You should be running another pump and regulator to keep things constant. However, on a 50 or 75 shot through a single fogger, it wont really make that big of a diference. It will be fat at the higher fuel pressure, but not that fat, because you will be running a small fuel jet.


FP is always 48!! It will always be 48 psi. Remember that if your FP goes up to 78, then you have 30 psi of boost. The boost works against the fuel trying to come out. 30 psi against and 78 psi of fuel pressure means your static FP is still 48!!
 

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Is it really worth it for a 50shot on a 6cylinder?

If you don't like the dry direct option why not just do a dry single nozzle and still let the AEM control it. Then you don't have to worry about all this FP crap as you can take care of it in the AEM EMS and you will save money on the kit as you only need "half" the parts.
 

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Bob - FYI, I have a 50 wet shot. My air fuel goes from 11.5 off nitrous to 11.0 with nitrous on the same boost level. Hope that helps.
 

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Life begins @ 30psi....
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Discussion Starter · #12 ·
Bob - FYI, I have a 50 wet shot. My air fuel goes from 11.5 off nitrous to 11.0 with nitrous on the same boost level. Hope that helps.
Beau -

Where are you picking up your fuel source?

Thanks,
Bob
 

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King of the NA-T's
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For the sake of argument, say you have 40 psi of fuel pressure at 0 psi of boost. When you run 30 psi of boost, the fuel pressure rises to 70 psi, but the fuel only flows at the delta across the fuel injector which is still 40 psi (70 psi of fuel on one end of the injector pushing against 30 psi boost on the other end of the injector). So basically you have the equivalent of a static fuel pressure of 40 psi of fuel at all times.

If your nitrous pressure is at 1000 psi, and you run 30 psi of boost, then basically your delta across the nitrous nozzle is 970 psi of nitrous pressure. This is only a 3% change in pressure... in reality your nitrous pressure changes more than that as the bottle cools off as you spray down the track. It's safe to say that you have the equivalent of 1000 psi of nitrous at all times

40 psi of fuel at all times, plus 1000 psi of nitrous at all times = nitrous a/f stays pretty consistant. :)




How in the hell does 30 psi of boost slow down the 1000 psi of no2 blasting its way out of the same nozzle that has already mixed the fuel and no2?

You should be running another pump and regulator to keep things constant. However, on a 50 or 75 shot through a single fogger, it wont really make that big of a diference. It will be fat at the higher fuel pressure, but not that fat, because you will be running a small fuel jet.
 

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Life begins @ 30psi....
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Discussion Starter · #14 ·
Nitrous express tech department just told me the same thing that Larry stated.

I am going to order the NX20923 kit from summit today. Is the anything else that is must have? purge kit ect ect?

Thanks,
Bob
 

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Just an old *******
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The no2 and fuel mix back in the nozzle, not at the tip of it. It could be argued that the presurized no2 draws the fuel out as it passes by sort of like a carberator works. The boost does not affect the fuel pressure at the nozzle, only at the fpr, just like it is desighned to do. I run a wet shot with 10psi of fuel pressure, wich is perfectly ok as long as you have the proper jetting.

Dave, thanks for clearing that up. I, being a grade school drop out illiterate, can hardle speak, much less explain things in english.

For the sake of argument, say you have 40 psi of fuel pressure at 0 psi of boost. When you run 30 psi of boost, the fuel pressure rises to 70 psi, but the fuel only flows at the delta across the fuel injector which is still 40 psi (70 psi of fuel on one end of the injector pushing against 30 psi boost on the other end of the injector). So basically you have the equivalent of a static fuel pressure of 40 psi of fuel at all times.

If your nitrous pressure is at 1000 psi, and you run 30 psi of boost, then basically your delta across the nitrous nozzle is 970 psi of nitrous pressure. This is only a 3% change in pressure... in reality your nitrous pressure changes more than that as the bottle cools off as you spray down the track. It's safe to say that you have the equivalent of 1000 psi of nitrous at all times

40 psi of fuel at all times, plus 1000 psi of nitrous at all times = nitrous a/f stays pretty consistant. :)
 

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Just an old *******
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You may want to call back and talk to someone else over there. You will get more than one version of a story depending on who you talk to. You however do not need to worry about all of this on a 50 shot.

Nitrous express tech department just told me the same thing that Larry stated.

I am going to order the NX20923 kit from summit today. Is the anything else that is must have? purge kit ect ect?

Thanks,
Bob
 

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9's Club
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...

Has anyone documented the gains of using a 50shot at the track in a auto? Meaning one pass with out spray, and then one with 50 shot comming off the line to build the boost...and the 60' difference?
 

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Beau -

Where are you picking up your fuel source?

Thanks,
Bob
I'm pretty sure that BL installed a Y immediately out of the fuel filter (which sits near the lower part of my driver side shock tower) and ran one line to the fuel rail and a new line to the nitrous setup. I have a purge kit as well.

I only tried to use my nitrous twice at the line during the TX2K7 test n tune on Saturday and I essentially messed it up both times (too much going on in the cabin: foot braking, e-brake, watching the lights, etc.), so I can't say how it feels on the launch. Perhaps I'll get it down one of these days.
 

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I was planning on simply picking up fuel from one of the ports on the FPR... I assume there isn't a n issue with it? Can one of you confirm?

Bob, I plan on a small wet shoht as well. I'll have different jets and work my way up 50 and 75 then to a max of 100 shot.
 

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I was planning on simply picking up fuel from one of the ports on the FPR... I assume there isn't a n issue with it? Can one of you confirm?

Bob, I plan on a small wet shoht as well. I'll have different jets and work my way up 50 and 75 then to a max of 100 shot.
I have seen it plumbed directly from the FPR as well.
 
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