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I have a question with setting up my shot on the new setup... i will be running close to 90 psi of fuel pressure at the top of the boost table.... and do not have an additional regulator for the nitrous system.. but on the launch i will be at about 60 psi of fuel pressure...

what fuel jet do you recommend for a 50 shot using your single nozzle system..

I have and will always use nx kits... i sell them at the shop as well... great products...:thumbsup:
 

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Thats the issue with using a 1:1 with nitrous you will have to be lean on the bottom to be right up top.
 

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If I'm not mistaken it should equal itself out. The rise in fuel pressure will be equall to the rise in manifold pressure hince (1:1). So the greater fuel pressure will be needed to combat the the manifold pressure that exist.

Lets say you had a steady 58 psi of fuel pressure injecting into a manifold with 10psi boost. Then you used the same 58 psi of fuel pressure to inject into a manifold with 30psi of boost. The effect would be the same as lowering the FP to 38psi because the boost pressure will be pushing on every opening to find a place to escape (including the fuel nozzle).

NE, correct me if I went wrong somewhere.
 

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Not the case, you are pushing fuel into a nozzle that has 1000 psi of nitrous pushing it along. Your fuel jet puts fuel into the nitrous and they mix and come out the nozzle. So if you have X fuel presure at Y boost then you start your one to one you increaseing X by Y and then you will should have to much fuel in your nitrous and will be rich. If you go small on your fuel jet to make up for being rich up top you will be lean on the the bottom because you are changing your X all the time. If that sounds crazy let me know and I'll explain diffrent.
 

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Not the case, you are pushing fuel into a nozzle that has 1000 psi of nitrous pushing it along. Your fuel jet puts fuel into the nitrous and they mix and come out the nozzle. So if you have X fuel presure at Y boost then you start your one to one you increaseing X by Y and then you will should have to much fuel in your nitrous and will be rich. If you go small on your fuel jet to make up for being rich up top you will be lean on the the bottom because you are changing your X all the time. If that sounds crazy let me know and I'll explain diffrent.
You are right, I wasn't taking into account the nitrous pressure that is gig along with the fuel.
If one wanted to be safer they could set the window switch for where ever there turbo reaches max boost. So most guys would do 3500-3900, and the real big turbo guys would have to wait a little longer.
 

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You are right, I wasn't taking into account the nitrous pressure that is gig along with the fuel.
If one wanted to be safer they could set the window switch for where ever there turbo reaches max boost. So most guys would do 3500-3900, and the real big turbo guys would have to wait a little longer.
At that point you should just got with a boost refrence activation cause one of the reasons for nitrous on a big turbo car is spool up.
 

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You will actually be a little richer with a FI car as the boost comes in. But not because of fuel delivery. :)

The Positive pressure effects the fuel AND the nitrous. So the car will actually be a touch richer because the fuel is correct, but the nitrous is slightly less, given it is not regulated. Example:

Srt4 with 58 psi fuel pressure on 20 psi. Bottle pressure at 1000.

We will jet the car for 58 psi.

Now as boost pressure comes in the regulator increases 1:1 in compensate. The fuel pressure at both the injectors and the fuel solenoid will be 78 psi at full boost. As both the nozzle outlet and the injector outlet are exposed to the positive intake pressure. they are corrected back to 58 psi. Leaving us with accurate fueling from the injectors and the nozzle.

Yet the nitrous is still effected by the positive pressure. Leaving a final pressure of 980 psi. This of course is a much smaller effect on overall nitrous function given the percantage difference is much less.
 
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