Bullitt gets a little juice
03-15-2011, 08:12 PM
#1
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Join Date: Sep 2009
Location: NC
Posts: 1,481
Bullitt gets a little juice
I just installed my nitrous kit and had it tuned today. We have a configuration that made 360rwhp/440tq with a nice stable A/F ratio. I ran out of nitrous before we finished experimenting with different configurations, but I am content for now with 360/440.
Classes are keeping me so busy this semester that I don't know when I'll get a chance to try it at the track (NO NITROUS on the street for me). I am expecting/hoping this will be enough to propell me to a sub 12.0 second pass. I'll start with the smallest jetting and get acquainted with how that runs before I bump it up to the 360/440 set-up.
NOTE: this is all with the stock fuel pump. I was concerned that the stocker would not support over 350rwhp, but it has been able to satisfy the 360rwhp level for me.
I'll update my sig with nitrous ET/Trap after I get a couple of passes in with it.
Classes are keeping me so busy this semester that I don't know when I'll get a chance to try it at the track (NO NITROUS on the street for me). I am expecting/hoping this will be enough to propell me to a sub 12.0 second pass. I'll start with the smallest jetting and get acquainted with how that runs before I bump it up to the 360/440 set-up.
NOTE: this is all with the stock fuel pump. I was concerned that the stocker would not support over 350rwhp, but it has been able to satisfy the 360rwhp level for me.
I'll update my sig with nitrous ET/Trap after I get a couple of passes in with it.
03-15-2011, 08:36 PM
#7
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Join Date: Sep 2009
Location: NC
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We ran a baseline pull before we started with the nitrous. The numbers were the lowest I have had since I added the cams/headers (270rwhp/279tq). Note: this is exactly the set-up I ran my 12.5@110mph pass with, so take that for what it is worth.
The net gain was 90rwhp/160tq, with what Zex calls the 125 shot. We scratched our heads today at the inability to get the HP numbers up at the rate we expected, but the torque numbers kept increasing as we progressed. We got around 68-69rwhp from the "75 shot" and around 79rwhp from the "100 shot." Seemed like we only gained around 10rwhp or so everytime we increased to the next higher (25hp) jet sizes. The A/F ratio was kept stable as we went up, so it was not due to changes in the mixture.
This is a Zex WET kit. The bottle pressure was right at 960psi for each pull, so there was no variation in pressure. We pulled a couple of plugs and checked them each time we went up a jet size. We made about 10 pulls before I ran out of nitrous in the bottle.
The net gain was 90rwhp/160tq, with what Zex calls the 125 shot. We scratched our heads today at the inability to get the HP numbers up at the rate we expected, but the torque numbers kept increasing as we progressed. We got around 68-69rwhp from the "75 shot" and around 79rwhp from the "100 shot." Seemed like we only gained around 10rwhp or so everytime we increased to the next higher (25hp) jet sizes. The A/F ratio was kept stable as we went up, so it was not due to changes in the mixture.
This is a Zex WET kit. The bottle pressure was right at 960psi for each pull, so there was no variation in pressure. We pulled a couple of plugs and checked them each time we went up a jet size. We made about 10 pulls before I ran out of nitrous in the bottle.
03-15-2011, 10:04 PM
#9
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Join Date: Sep 2009
Location: NC
Posts: 1,481
I agree that track numbers are a far better representation of how the car runs.
Yes, I am running a window switch. However, I am a little unhappy with how the skip shift mechanism works. It simply counts how many times you exceed the high limit set for disengagement to know what gear you are in. So basically, you have to rev past the high cut-off point for it to determin that you have run thru a gear a changed to the next. Example: if you have the high cut-off limit set to disengage nitrous at 6300rpm, you would have to rev past 6300rpm in first gear and drop the rpms before it would activate the nitrous at next WOT if you are set to skip nitrous in first gear. So if you then missed your shift point and shifted at 6250rpm, nitrous would not activate in second gear and you would have to rev past the 6300rpm in second gear before nitrous would activate at WOT in third gear...
This is an unfortunate configuration for the skip shift option!!!
Although more costly, a nitrous controller that has higher capabilities may be a worthwhile investment if you are serious about running juice at the track.
Yes, I am running a window switch. However, I am a little unhappy with how the skip shift mechanism works. It simply counts how many times you exceed the high limit set for disengagement to know what gear you are in. So basically, you have to rev past the high cut-off point for it to determin that you have run thru a gear a changed to the next. Example: if you have the high cut-off limit set to disengage nitrous at 6300rpm, you would have to rev past 6300rpm in first gear and drop the rpms before it would activate the nitrous at next WOT if you are set to skip nitrous in first gear. So if you then missed your shift point and shifted at 6250rpm, nitrous would not activate in second gear and you would have to rev past the 6300rpm in second gear before nitrous would activate at WOT in third gear...
This is an unfortunate configuration for the skip shift option!!!
Although more costly, a nitrous controller that has higher capabilities may be a worthwhile investment if you are serious about running juice at the track.
