PDA

View Full Version : WHat's the biggest shot I can trigger at 15psi??


JQmile
04-17-2010, 11:37 AM
Going to the dyno next week with more nitrous....was wondering what the biggest jet anyone has used triggering at about 15psi without putting the fire out. I'll have plenty of fuel. I was thinking about starting with a .99 first stage, .135 second and going up from there.

CL2000
04-17-2010, 11:50 AM
That should be ok as long as you start your pull around 2000 and how does your second stage go off

morkable
04-17-2010, 01:39 PM
at one time I ran a .047 shot (about 50 hp) on a WOT switch, that worked quite well

JQmile
04-17-2010, 02:31 PM
That should be ok as long as you start your pull around 2000 and how does your second stage go off

By flipping a switch....gotta be quick! :tree:

carcrafter22
04-17-2010, 02:51 PM
I tried a .120 jet in each stage on my duramax once (2 stages) and all went well. I would imagine common rail injection pressures ( I was commanding 27,000 at the time if I remember right) would hold up better to VE injection pressures.

Does that sound right? Would the fire be harder to put out at 5000 psi than it would be at 26,000 psi?

GRotman
04-17-2010, 03:06 PM
In mu experience, it has more to do with turbo selection than fuel systems. Small turbos can take bigger shots earlier. My theory being that they heat the air up more.

JQmile
04-17-2010, 06:06 PM
In mu experience, it has more to do with turbo selection than fuel systems. Small turbos can take bigger shots earlier. My theory being that they heat the air up more.


That's my thinking too....and the fact the truck is non-intercooled, I figure I'll be able to run a pretty big shot without putting the fire out...especially if I brake boost a little on the dyno.

Red Stroke
04-17-2010, 06:42 PM
I never had problems as long as I was above 15-18 psi, if you are under you get a nice nitrous backfire. I was hosing 3 stages without any jets at just over 15 psi, then 2 more after that.

JQmile
04-17-2010, 09:44 PM
I never had problems as long as I was above 15-18 psi, if you are under you get a nice nitrous backfire. I was hosing 3 stages without any jets at just over 15 psi, then 2 more after that.

I figured if anyone would know, you would.....thanks for chiming in. Looks like the .156 jet it is!! :bow::nos:

Red Stroke
04-18-2010, 09:47 AM
Did you pin out your solenoids? Thats why I didnt use jets, the solenoid is already the restriction, and most of the time the solenoid is smaller than the jet you are trying to use.

JQmile
04-18-2010, 12:20 PM
The NX kit has two .157 solenoids with twin -4 lines, so flow shouldn't be an issue. Where was your bottle pressure at when you made those runs Adam? Did you have heaters on all of them?

04 hotrod
04-18-2010, 12:48 PM
i have 2 200 hp stages and if you fire them once you are under boost it works fine but if you need it to build boost useing them use them in stages because once you fire the first itll start into boost then the second will be fine

Red Stroke
04-19-2010, 06:58 PM
The NX kit has two .157 solenoids with twin -4 lines, so flow shouldn't be an issue. Where was your bottle pressure at when you made those runs Adam? Did you have heaters on all of them?

If you are only making one nitrous run you dont really need the heaters. I used a pressure switch hooked up to the heater relay and it kicked off the heaters at a preset pressure dont remember what that was though...

John Robinson
04-19-2010, 07:55 PM
What turbo ? What size gate? Ive seen that shot pop some decent turbos.

JQmile
04-19-2010, 07:56 PM
62mm turbo, internal gate, plus 38mm external gate.

CL2000
04-19-2010, 08:50 PM
You will be more than fine with that set up, I would hit your second stage at 2500rpm. Running to shots that big it can be easy to put the fire out spraying the second too soon. I know this is why Adam Winslett and I changed our set ups when we started playing with that much n2o and we would hit our second stage at 2500rpm

WINspeed
07-07-2010, 06:16 AM
RPM has more to do with the size jet you use than boost. Don't hit a .157 too early, it could be catastrophic if you do.

I usually run a .088 first stage triggered at about 2k and a .125 second.