Lean at the hit
02-05-2012, 05:23 PM
#21
He's gonna need the pump regardless because of the fuel volume needed. Now you will get a lean spike because of the differences of pressure between fuel and nitrous. It just depends how long it goes lean for... There are obvious ways to combat this but it just isn't going to go away. Equal lengths same opening time 900psi gets there much faster than 60... trying to minimize that time is what you need to do
and yes you can pull plenty of fuel off the stock rails if needed... been there done that
and yes you can pull plenty of fuel off the stock rails if needed... been there done that
02-06-2012, 11:02 PM
#27
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if your really worried about a lean spike i wouldnt mess around trying line sizes i would just buy a controller like the microedge that can control the fuel and nitrous solenoids independently and set up the delay, a window switch and a wide open throttle all in one along with a lean safety shut off... thats full of win.
fwiw i believe the problem does not come from the fuel rails or anything else but the fact that the fuel in the fuel line after the solenoid gets siphoned out of the line as air is drawn passed it. what i would do during my track runs is briefly trigger the nitrous during the burnout to fill the line.when i launched i would get no spike. If i didnt i would see a lean spike at launch all the way up to 20 afr very clearly in my logs and very audible when the nitrous hit (almost like a backfire). When i hit the nitrous in the burnout i would get no lean spike in the logs and no audible cues.
So obviously if you have a very short fuel line it will fill up with fuel much faster then a 18 inch long line, but that limits solenoid mounting location to the throttle body, which is great if thats where you want to mount it
fwiw i believe the problem does not come from the fuel rails or anything else but the fact that the fuel in the fuel line after the solenoid gets siphoned out of the line as air is drawn passed it. what i would do during my track runs is briefly trigger the nitrous during the burnout to fill the line.when i launched i would get no spike. If i didnt i would see a lean spike at launch all the way up to 20 afr very clearly in my logs and very audible when the nitrous hit (almost like a backfire). When i hit the nitrous in the burnout i would get no lean spike in the logs and no audible cues.
So obviously if you have a very short fuel line it will fill up with fuel much faster then a 18 inch long line, but that limits solenoid mounting location to the throttle body, which is great if thats where you want to mount it
Last edited by got-a-ls1; 02-06-2012 at 11:14 PM.
02-07-2012, 11:26 AM
#29
if your really worried about a lean spike i wouldnt mess around trying line sizes i would just buy a controller like the microedge that can control the fuel and nitrous solenoids independently and set up the delay, a window switch and a wide open throttle all in one along with a lean safety shut off... thats full of win.
fwiw i believe the problem does not come from the fuel rails or anything else but the fact that the fuel in the fuel line after the solenoid gets siphoned out of the line as air is drawn passed it. what i would do during my track runs is briefly trigger the nitrous during the burnout to fill the line.when i launched i would get no spike. If i didnt i would see a lean spike at launch all the way up to 20 afr very clearly in my logs and very audible when the nitrous hit (almost like a backfire). When i hit the nitrous in the burnout i would get no lean spike in the logs and no audible cues.
So obviously if you have a very short fuel line it will fill up with fuel much faster then a 18 inch long line, but that limits solenoid mounting location to the throttle body, which is great if thats where you want to mount it
fwiw i believe the problem does not come from the fuel rails or anything else but the fact that the fuel in the fuel line after the solenoid gets siphoned out of the line as air is drawn passed it. what i would do during my track runs is briefly trigger the nitrous during the burnout to fill the line.when i launched i would get no spike. If i didnt i would see a lean spike at launch all the way up to 20 afr very clearly in my logs and very audible when the nitrous hit (almost like a backfire). When i hit the nitrous in the burnout i would get no lean spike in the logs and no audible cues.
So obviously if you have a very short fuel line it will fill up with fuel much faster then a 18 inch long line, but that limits solenoid mounting location to the throttle body, which is great if thats where you want to mount it
02-07-2012, 03:36 PM
#33
fast forward to 1:15http://www.youtube.com/watch?v=4pW6VSgEmrA
yes sir, we only ran that jet to the 1/8 for the heads up stuff, no idea if we will do it this year yet...
02-07-2012, 03:59 PM
#36
Long story
Last year stock heads about 380hp unlocked and about 275 of nitrous
1.32 9.52 140
This year we have only went out once that resulted in the video above
455hp unlocked 200 nitrous and a bad lean pop
1.43 9.52 140
We have fixed our lean problem and hope to go 9.0s 9.teens next time out
Last year stock heads about 380hp unlocked and about 275 of nitrous
1.32 9.52 140
This year we have only went out once that resulted in the video above
455hp unlocked 200 nitrous and a bad lean pop
1.43 9.52 140
We have fixed our lean problem and hope to go 9.0s 9.teens next time out
02-07-2012, 04:24 PM
#37
Long story
Last year stock heads about 380hp unlocked and about 275 of nitrous
1.32 9.52 140
This year we have only went out once that resulted in the video above
455hp unlocked 200 nitrous and a bad lean pop
1.43 9.52 140
We have fixed our lean problem and hope to go 9.0s 9.teens next time out
Last year stock heads about 380hp unlocked and about 275 of nitrous
1.32 9.52 140
This year we have only went out once that resulted in the video above
455hp unlocked 200 nitrous and a bad lean pop
1.43 9.52 140
We have fixed our lean problem and hope to go 9.0s 9.teens next time out
