First thing I need to say is THANKS to Dave and the guys at the N20 outlet, his stand alone fuse dedicated system is great and he has been a huge help!
Now, onto the good and the bad.....
The good.... I've ran my cam only z28 on a zex 175 previous to my new kit and best was a 10.8@127 w/ a poor 1.56 60ft. I get my NX direct port kit on and w/ the 200 shot (26n 14f fuel pressure at 42# running 12.2-12.4ish 15timing) the car went 10.17@133 w/ a 1.36 60ft!!!!!!! Now this being kinda odd, I decide to put a 75 shot in the zex kit and hit that on top of the 200 in 2nd gear. Mph dropped to 132 and it ran 10.2 60ft was worse w/ a 1.44, a/f was a 11.8ish.
The bad...... So I get home and decided ok, forget 2 stages, ill just toss in the 250 jets.... 28n and 16f. Made a test pass car was PIG rich. Dropped fuel pressure down to 38 and made another test, now its still rich (11.0-11.4ish). This time i made a complete pass and the car went 10.15@134 but w/ a 1.46 60ft. So, I decided to drop the fuel pressure lil more down to 33 and made another pass. This time 11.4-11.7ish but odd part is i ran 10.2@132 w/ a 1.39 60ft.....
So this leaves me standing w/ a few questions....
1. Why is the car running so rich w/ the 28n 16f jets? How come I had to bump the fuel pressure down so low and is it really a good idea to do that?
2. Why is it that when I hit the second kit I gained nothing? I know the kit works and bottle press was good, I made a pass w/ just the zex kit and the car went 11.0@119 on just the 75shot.
3. How come it only picked up 1 mph on the 250 shot? I realize the 60ft was worse and it was running quite a bit richer, after leaning it out and getting it to hook what should i expect?
And yes this is on a stock heads cam only STOCK BOTTOM END! plan to hit it w/ 325.... 250 direct port and 75 zex
lil backround too, it has a th400 w/ 3600 stall, and from calculators seems to have about 11 percent slippage and im running ngk br8ef plugs gapped at .028
My friend thought it would be funny to throw a bouncy ball at my car when he was going 55mph and mine was going 15. I thought it would be funny to have sex with his sister.
Gear is a 3.50 on a 28'' tire, shifting at 6500 going through the traps at 6350 @ 134. Punching all that in the calculator only comes out to about 11 percent slippage.....
Some kind of restriction on the nitrous side? That would cause it to be prety fat.
__________________ 2002 Trans Am m6: stock heads and bottom end, 10.02 @ 136 on a 150 shot, 3400lbs
Tuned and built by me, welded/fabricated by Madman.
2007 Dodge Ram 2500 Q/C m6
"If it flys, floats, or fucks you're bound to have trouble with it."
If you have a long -4 feed line with a bunch of fittings prior to the solinoids(90* fittings, etc), it could have maxed out the flow capabilities of that line.
We've put 300+ through a -4 line, but it was a straight shot into a single noid....
I say you are out flowing the heads...they just can't flow all that power. You may need bigger heads, or maybe better exhaust cam lope profile. But man you are flying with that setup. How much do you weight " the car that is"
Im guessing your just going to give the car hell and see what you can get out of it before it blows correct. You dont really expect this to last right? lol
Nice times BTW! Keep us updated!
__________________ 2002 Black Z28 SLP Lid and Bellow, 3:73s, DRs
Location: In the garage, working towards a 2900 lb raceweight :D
Posts: 10,765
I'd guess you're limited by the camshaft/head flow and rpm of the engine.
11% for a nitrous converter isn't great, I'd like to see it around 6% to be honest, but if you tighten it up that much you probably won't have enough power to run the first 1/2 of the track.
What noids are on the car? probably out of noid so the extra nitrous jet does not matter.
if 1 kit=200 shot ran at 12.5 A/f and the 2nd kit brings it to low 10's it will not pick up hp.
If your not out of noid the 2nd kit and now the bigger jets are way to rich and you need to get the tune right.
hmmm, you could be right on the noid thought, but they are from the n2o outlet, i believe the fuel is like a .310 and nos is like .126? or something along those lines, they are large in size i know that prob does not say much though.
as for when the second kit came on, the af was in the hi to mid 11s vs mid 12s, and the second kit uses a different set of noids bottle and line.
i am running basically a fully stock ignition setup as well, meaning factory coils and some junk auto zone wires, can it have something to do with this also?
We also once had an issue with a zex kit because they use the lines that have the 90* bent ends on there . They were limiting flow to about a 150 shot. changed to a regular line and it picked right up. post a pic of your setup.
__________________ Steve
Old setup
HK 408 ,AFR, Hydraulic roller
9.1 @149 in PGD trim
2007 Pump Gas Drag Champ
8.9@157
went from 200 to 250 (stock bottom end) 
