NITROUS PERFORMANCE PROBLEM

[overpower]

I installed a Zex 100hp wet system. Install went great.. No problems. Window switch and WOT tested and work perfectly. Heres the problem.. We tested it this afternoon and it really didn't seem like that big of a kick.. In fact, I had to pull over and check the system to make sure it was firing.. It was. The car has lots of bolt ons, and has a real kick in the seat to begin with. JLT Cold Air, JBA Long Tube Headers, Borla Exh, IMRC Delete, Bama Custom Tune, and 4:10 Gears. The gearing always made the car accellerate like a bullet. With the NOS Armed, we thought we felt a difference at 5000+ rpm, but it is so subtle, I feel like something is not right. The window switch is set to 3000 - 6500 rpm, plus WOT. I even tried bypassing the window switch (I included a switch under the hood to allow the mode swap), but again, the same result. My basic question is with my current setup (especially the gearing), under what conditions would I notice the biggest difference? We performed the exact same runs with and without the NOS armed and although we had to keep things under 110mph, (due to where we tested), there wasnt much of a difference. Shouldn't there be a HUGE NOTICABLE Difference? What am I missing?

 

[DAKDOG99]

I have the same kit set up on a 100 shot. Went to the track last night. My car ran strong with bolt-ons and motor tune. But with the nitrous tune and on spray it does not feel like much of a difference. But on the spray I was having serious traction issues. When it did hook it ran 1/2 second better than my best motor pass. But I was expecting more. Were you having traction problems?

 

[overpower]

no even from a roll i did not notice a very big difference............ what conditions would I notice the change the most....and again isnt it supposed to be an obvious huge difference...... does it have anything to do with my 4.10s............ is it possible its already accelerating so hard that the change is only noticible when timed? im kinda lost guys help me out here

 

[Stan Weiss]

What size is the Nitrous jet?
What was your bottle pressure?
Did you purge the system first?

 

[overpower]

I have a .46 nitrous jet and .30 fuel jet in.....those were the jets for a 100 shot in the back of the zex manual.... the bottle pressure was 800-900 psi...... i do not have a purge however i ran enough passes so that any air in the line would be gone..... any ideas?

 

[Stan Weiss]

The manual says to use those jets with what bottle pressure and what fuel pressure? Since I do not see a location what was the air temperature and do you have a bottle warmer?

 

[cobra2798]

100 shot on a zex kit is more like a 75 shot with most other kits, but still you would notice a big difference. Wish I could help but im a little lost as to what the problem may be

 

[overpower]

its for 900 psi on the bottle and I believe 40 psi on fuel i dont have a bottle warmer but im in nj and it was a warm day and bottle pressure was consistant............. when you say a 100 shot in zex is like a 75 shot are you saying i just need to up the shot or something else is incorrect..... to my understanding a 100 shot is the most stock internals can take on my car

 

[cobra2798]

its for 900 psi on the bottle and I believe 40 psi on fuel i dont have a bottle warmer but im in nj and it was a warm day and bottle pressure was consistant............. when you say a 100 shot in zex is like a 75 shot are you saying i just need to up the shot or something else is incorrect..... to my understanding a 100 shot is the most stock internals can take on my car

Zex kits make less at the wheels than say NX or NOS systems, its a known fact. Is the car tuned? Its not needed for a 100 shot but will help you see the full potential of the spray. you can run a 125 shot no problem with a tune on that car....even 150 is with a good tune but most stop at 125. You should feel a huge difference on a 100 shot. Ive run a 100 shot on 2 of my cars(NX wet kit and DynoTune dry kit) and you notice the difference for sure. I would go over the entire system again. Check the WOT switch. Arm the system with the car off and click the switch and you should hear the spray come out.....at least hear the selinod click on. Also the purge is not needed but with a clear line it will hit much harder....and its cool to purge a car at a stop light

 

[Tim2002GT]

The combination of the low bottle pressure + Zex kits rated at the crank could be to blame for the problem. Try it again with bottle pressure between 900-1000psi.

If you don't have a heater, take the bottle and sit it upright in about 3" of warm/hot water for a few minutes. It won't take long if the waters hot. Don't walk off and leave it in the hot water though because the pressure will climb fast. When the pressure reaches over 1000psi put it back in the car and try another run. Also make sure the bottle valve is completely open.

I also have 4.10's and I can feel a big difference with just my 75hp jets installed.


btw: You were not spraying the car with your performance tune loaded were you? That is a bad idea as performance tunes advance timing. If you don't have a tune for your nitrous, the stock tune will be fine with a 100shot or less. Also do you have the correct spark plugs for the nitrous. I use NGK TR6's which are 1 heat range colder than stock and they're gapped at 0.035.

 

[overpower]

well i tried it today when the roads where dry (werent yesterday) and really felt the difference....it was great! thanks for the help guys