jet sizes for 50 and 75 shot

[bribri]

What are you guys running when looking for a 50 and a 75 shot? I called NOS and told them the fuel pressure (58 psi) and these are the jets they suggested.

from NOS techline

50 shot
37N
20F

75 shot
41N
24F


Any suggestions on if these are good starting numbers? Mods for my 04 are
(stock turbo)
(stock fuel system)

Stage1
Needswings cutout no cat w/ borla catback
BFMIC
Short ram
AGP WGA with MBC at 17-14 psi


Also should i lower the boost once i start spraying? Or will I be ok with it jumping up a few lbs?

Thanks,

Brian

[Rhunter]

Quote: Originally Posted by bribri

What are you guys running when looking for a 50 and a 75 shot? I called NOS and told them the fuel pressure (58 psi) and these are the jets they suggested.

from NOS techline

50 shot
37N
20F

75 shot
41N
24F


Any suggestions on if these are good starting numbers? Mods for my 04 are
(stock turbo)
(stock fuel system)

Stage1
Needswings cutout no cat w/ borla catback
BFMIC
Short ram
AGP WGA with MBC at 17-14 psi


Also should i lower the boost once i start spraying? Or will I be ok with it jumping up a few lbs?

Thanks,

Brian

that depends. How much does your boost spike when you have the cut out open? You will gain at least a pound of boost from the open pipe and you will gain more boost when you spray so you might need to adjust you boost levels accordingly. If you have high enough octane fuel in your tank, I think you will be ok to spike 20 for a couple of runs down the drag strip. I would not spike twenty all day everyday on my car but I think it's fine for once in awhile at the track. You should have plenty of fuel so I say go for it

[bribri]

Quote: Originally Posted by Rhunter

that depends. How much does your boost spike when you have the cut out open? You will gain at least a pound of boost from the open pipe and you will gain more boost when you spray so you might need to adjust you boost levels accordingly. If you have high enough octane fuel in your tank, I think you will be ok to spike 20 for a couple of runs down the drag strip. I would not spike twenty all day everyday on my car but I think it's fine for once in awhile at the track. You should have plenty of fuel so I say go for it

*EDIT* South Florida serves 93 octane

Well I have the boost set to 17psi with the downpipe open. Honestly I don't think I will be spraying the car that often. Im just gonna have it if I need it and for the track (which i go to twice a year if that)

Any ideas on the jet sizes? Im looking for info on it. Im gonna have a wideband to tune the car with. Its not mine so im gonna have to give it back after im done getting the jets right. What kind of A/F ratio should I be aiming for?

Thanks

[Rhunter]

Quote: Originally Posted by bribri

*EDIT* South Florida serves 93 octane

Well I have the boost set to 17psi with the downpipe open. Honestly I don't think I will be spraying the car that often. Im just gonna have it if I need it and for the track (which i go to twice a year if that)

Any ideas on the jet sizes? Im looking for info on it. Im gonna have a wideband to tune the car with. Its not mine so im gonna have to give it back after im done getting the jets right. What kind of A/F ratio should I be aiming for?

Thanks

When I plan on spraying I up the octane. 93 is great compared to the 91 piss water they have out in Cali but I personally won't spray on 93. I recommend some race gas or at the very least N.O.S brand octane booster (about 7.00 a bottle and works!!!) or Torco fuel excelorater (about 17.00 a can). Better safe than sorry.

As far as A/F ratio, I have not gotten to the point of my nitrous tune. I've only sprayed the car like 4 (race gas or torco each time)times, and since I've been back to the states I have not had time to get into tuning the car.

I'm gonna get a A/F reading before spraying, then spray the car and get another reading. From the 2nd reading I will adjust the fuel jet. If it car is rich (most seem to be when spraying) I'll go down one fuel pill size. If it looks lean, then I'll try go up one fuel pill size size.

Don't get to rapped around the axle with HP jetting. You BP will also play a big part in "how much" you are spraying. I would start with jetting for a 75 shot and adjust your fuel pill from that jetting.

I'm sure the real pro's will chime in and add anything I've missed.

[bribri]

Thanks for the info...anyone got input on jet sizes? Install is on Sunday

Quote: Originally Posted by Rhunter

When I plan on spraying I up the octane. 93 is great compared to the 91 piss water they have out in Cali but I personally won't spray on 93. I recommend some race gas or at the very least N.O.S brand octane booster (about 7.00 a bottle and works!!!) or Torco fuel excelorater (about 17.00 a can). Better safe than sorry.

As far as A/F ratio, I have not gotten to the point of my nitrous tune. I've only sprayed the car like 4 (race gas or torco each time)times, and since I've been back to the states I have not had time to get into tuning the car.

I'm gonna get a A/F reading before spraying, then spray the car and get another reading. From the 2nd reading I will adjust the fuel jet. If it car is rich (most seem to be when spraying) I'll go down one fuel pill size. If it looks lean, then I'll try go up one fuel pill size size.

Don't get to rapped around the axle with HP jetting. You BP will also play a big part in "how much" you are spraying. I would start with jetting for a 75 shot and adjust your fuel pill from that jetting.

I'm sure the real pro's will chime in and add anything I've missed.