So I finally got my car on the dyno with the bottle and the numbers were extremely disappointing. I'm running a Nitrous Outlet LS1 plate kit with NX Lightning solenoids, trick window switch set at 3k and 6k and Zex bottle and bottle warmer. Bottle pressure was about 900. Car made 318 on motor on this particular dyno, which everyone said was giving low numbers (approximately 5-10% less from what others said they had run before). I had gone 331 on this same setup on another dyno. However, I only made 383/426 on the spray, with the 150 pills in. AFR peaked on the hit at 13.9 and then tailed down into mid 11's throughout the run. What do you guys think could be wrong and do you have any suggestions? I know Nitrous Outlet kits are supposed to be rated at the wheels, so where was my 468HP?

Any suggestions (intelligent ones) would be appreciated.

Thanks!
99 FRC

 

I am gonna say up the bottle pressure for starters.

Here are three plate dyno's on my setup from a couple years ago, jetting is on the sheet, and I am a A-4 so yours should be about 10 HP or so higher. This was a totally stock LS1 A-4. My Baseline was 300 RWHP. Bottle pressure about 1000

Here is the jetting sheet from Dave

 

So, you got 114 RWHP from a 150 shot? Also, I see that you chose to go 62 and 36 on the jetting, when the chart called for 62 and 38? Was that because of your AFR? Mine had a small spike to 13.9 when it kicked in, but basically stayed in the mid-11's the rest of the way. You think I should use the same jetting as you?

Thanks for jumping in!
99 FRC

 

Those #'s were totally Stock, I found the recommended jetting to be rich so we jetted 2 smaller on the fuel. Trends from reading the boards were stock guys were a bit rich, and guys with bolt ones were a bit lean. You should be ok with LT's I would think. After my Bolt on's (H/C/LT) I was lean.

Having logged fuel pressure when trouble shooting my system, the lean spike you see is the fuel rails losing pressure when the fuel noid opens but it recovers so you should be ok pump wise. I have a lean spike for about .7 seconds, when spraying to 525 RWHP but it recovers nicely.

I think if you up the pressure (Dave uses NX jetting and bottle pressure recommendations from NX) you will probably see you will be really close to the 150 your expecting. I think Dave tries for 11.8 for the AFR.

 

Thanks, beer! I just bought this stupid Zex bottle heater and it won't get the bottle pressure any higher than 950. Looks like I'm in the market for another.

99 FRC

 

I think it's you jockeying for a new kit with that post. You get an "A" for effort, though. Fortunately, Nitrous Outlet has already hooked me up with everything I need. I just need to get it dialed in.

99 FRC

 

What torque did it make on motor? I see the nitrous torque but not on motor. Where is the timing? My car put down 361 343 on motor and 502 585 on a 150 jetting through a nos plate with 1050 bottle pressure. Something is terribly wrong with the combination or you might not be on the right jetting, recheck the jetting and get us the numbers, hope to help, Josh

 

318/304 on motor with a nitrous tune from LG Motorsports (4 deg. retard).

Thanks!
Scott

 

It should be in the 450 range on the gas then. Even at 900 psi it still should make way more. What jets are in the plate?

 

Clutch slipping maybe? We dynoed a manual with a Zex dry kit and above 400 HP the clutch slipped, he put in a new one shortly after, although did not go back to the dyno.

 

Clutch is solid. They were monitoring it on the dyno because they had the same thought. It's basically a Textralia oz700, so it's stout.

99 FRC

 

What jets are in it?

 

It's been raining, so I haven't been able to double check them.dum I'll post when I do.Thanks again!99 FRC

 

I had the 62 nitrous and 38 fuel in.

99 FRC

 

So I was trying to figure out what was up with my bottle heater and I noticed that it kept shutting off every few seconds and wouldn't get the pressure above 900lbs. I decided to take the heater apart to see how it worked and try to fix it. This is my second bottle heater and I wasn't too happy about spending another $130 on another one. Any way, the assembly below was encased in rubber, so it cut all around it with a pocket knife. I noticed the little metal tube (I cut one of them off) seemed to be either a heat switch or timer of some sort, so I bypassed them by soldering the two leads together. Now the heater stays on and I reconnected the bottle pressure shutoff switch from my other heater kit to regulate the pressure. I bought this heater because it had the built in cutoff switch, but it looks like the old-school pressure switch is still the best way to go.



99 FRC

 

I have tried all the different transducers, temp and pressure based. So, in the end, none worked the way I wanted so we have by passed all auto control and prefer the manual method. This way the pressure can be maintained exactly at the psi desired. Just make sure it's key/ign activated so when you shut your car off it will be turned off automatically in case you forget.
Robert

 

Ok, so I put my bottle heater back on with the modifications above and got the bottle pressure up to 1050lbs. and sprayed it again (on the street). It definitely sprayed better than before, but still hit no harder than my Zex kit 100 shot and I've got the 150 jets in. It seems to stumble a bit when the spray comes on, and feels like it's getting too much fuel.
My theory is that the fuel is spraying harder since I switched to the Lighting Solenoids, and I should probably drop the fuel jetting a little. My question is would that theoretically cause an increase in RWHP, without increasing the nitrous jetting? So, all other conditions remaining the same, would reducing the fuel jetting cause an increase in RWHP if the previous jetting was too rich? Any theories about how much might be gained?

Thanks again!
99 FRC

 

Yes, for sure. If your rich and lean it out an increase in hp will be had. You really should be using a WB though so you know for sure this is what you want to do. Or reading plugs will suffice.
Robert

 

Well, A/F was in the low 11's on the dyno, so I know I have a little room to work with. Any idea how much the A/F (and RWHP) would increase if I went from a 38 fuel to a 36 fuel? I wonder if Beer99C5 would chime in since he made this exact adjustment. I can go back to this same dyno to get an A/F reading, but I want to have a good idea that the setup is going to perform before I go back.

Thanks again!
99 FRC

 

changing out the fuel solenoid will not increase your fuel pressure, that is definitley not what is going on. your A/F ratio seemed pretty good last time around, if you bumped up nitrous pressure from 900 to 1050 without changing the fuel jet then you are leaning it out. So you wouldnt want to do what beer did in going with a smaller fuel jet. In his case he was running slightly rich and wanted to get the A/F up a little. if you peaked at 13.9 and leveled down to mid 11's on 900 then you are in a good range. Since you increased the nitrous pressure you need to compensate that by increase the orfice size of the fuel jet. I think that will get you closer to the number you are looking for