JonGTR

Does the Zex kit modify the fuel flow in any way to add more fuel in relation to the amount of nitrous?

JAWS 021

yup

it does it all by pressure
For every nozzle you use with the nitrous,... there is a nozzle that corresponds to the fuel

wink

JonGTR

So, there is a fuel line that taps into the stock line and shoots additional fuel into the intake with the nitrous? Isn't that what a "wet system" is? I thought this is a "dry kit".

From what I've gathered, a "wet system" uses a seperate fuel line injecting fuel into the intake and a "dry system" uses the stock system to inject more fuel. How exactly does the Zex system tap into the stock fuel system? What does it do to it?

Cheuk in Seoul

The nitrous line goes into the purple box "control unit"... when flow is seen in the nitrous line, the control unit ups the fuel pressure of the stock fuel pressure regulator.

The additional fuel is gained by increasing the fuel pressure through the stock injectors, not through a seperate injector or nozzle.

So it is a dry system.

JonGTR

I guess it knows what jet you have by the velocity of the nitrous. How does it know how much to raise the fuel pressure according to your specific car?

Thanks.

Cheuk in Seoul

It doesn't really know the jet size. That' why it comes with different jets for both the fuel pressure "adjuster" and the nitrous. I think in actuality it reads the pressure and just the presence of flow.

I usually start with a slightly richer fuel jet than recommended.. then test it on a dyno with a wide band O2. Then lean it out if it needs it.

With the selection of jets, you can get pretty close to the 12:1 or 13:1 ratio that I would recommend for nitrous runs.

erikgsi

on my accent im using the 55 hp jet and the 65 fuel jet so i would be running a little rich seems to work great this way

JonGTR

Could I check this with a simple A/F guage? Nearest dyno is 100+ miles away.
So a wet system would be better then so you wouldn't have to worry about the fuel/nitrous mixture? What type of system would you recommend (wet or dry)?

Cheuk in Seoul

I recommend a dry system for low power applications <75 hp. But for serious nitrous power, a wet direct port is the way to go.

You could test it with just a wide band O2 sensor... some shops will have these and no dyno. A cheapy O2 sensor might do it. Or you could do as ZEX recommends... reading spark plugs.

JAWS 021

for high applications,... the venom kit would be good as well. For some that have turbos or chargers with bigger injectors, the venom kit taps into the electrical wiring and pulses the injectors to squeeze out more fuel. The system also adjust how much fuel will be coming out. It also taps into your 1st 02 sensor, just to ensure you got the right amount of fuel wink
My kit will be put to the test in about a month

WARNING!
WITH ZEX please make sure the clamps are extremely TIGHT,... i thought mine where, but i was wrong. Clamp down both sides of the nitrous fuel pressure lines.