Zex Wet NOS Kit Questions

[NSX-Files]

So I have a Zex wet nitrous kit that came with a Lotus Esprit Turbo SE I used to have. The kit is just sitting around in my garage, and I'm thinking of installing it on the NSX. I would probably only use the nitrous/fuel jets that yield 55HP since the manual says no retarding of timing is needed at that level (although I have jets for 65 and 75HP, but that requires retarding timing 2 and 4 degrees respectively). Some questions:

What's the best place/way to tap into the fuel rail - at the bolt on top of the fuel filter, or at the fuel pressure regulator at the end of the injector rail? What fittings would I need to get?

Where have others installed the fuel/nos nozzle? Picts please. I'm thinking it could go in the 1/2" space between the air filter box and the "accordian hose" feeding the throttle body (near where the steel worm-drive clamp is).

Where can I tap into the throttle position sensor wire to trigger the Zex NOS management computer. It monitors the voltage off this wire to know when you're WOT to trigger nos spray. Can someone ID the wire color and location?

I have an SOS chip installed in the ECM that came with my car. Does this chip advance timing and will that cause a problem? (I don't have a stock programmed chip).

Will I need to upgrade the fuel pump? How hard a job is it to install a Walbro 255?

The NSX is a 91 with 67k miles and a healthy engine (198-200psi on all cylinders except one with 195psi). Other mods are a Dali fresh air intake scoop, UNI foam filter, Comptech headers, oem cats, Comptech exhaust.

Any advise would be appreciated.

David

 

[CB169]

your best bet is too have a shop that has experience with nitrous install the kit
based on your questions, and as far as the ECU program I would use the 55hp because most aftermarket programs just add fuel and timing, and run a step colder plug because of your climate. If u had the stock ECU you could run a 75hp with no problem, I've been running a 75 shot for 6 years with no problems at all. Good luck

 

[NSX-Files]

I'm ready to install. For those that have wet NOS installed, where did you tap into the fuel supply?

Where did you put the nozzle?

Are you running the stock fuel pump or upgraded?

Thanks for any info!

 

[angus]

get a stock ecu .

 

[FeetFxr]

Send an email to BadCarma http://www.nsxprime.com/forums/member.php?u=5292 If you get a response, it will be reliable info. He's the NOS expert here.

 

[NSX-Files]

get a stock ecu .

I just got a stock ECU in the mail Tuesday! So I'm set there. Thanks for the advice!

 

[DutchBlackNsx]

Send an email to BadCarma http://www.nsxprime.com/forums/member.php?u=5292 If you get a response, it will be reliable info. He's the NOS expert here.

Very good advise indeed.

 

[CB169]

I'm ready to install. For those that have wet NOS installed, where did you tap into the fuel supply?

Where did you put the nozzle?

Are you running the stock fuel pump or upgraded?

Thanks for any info!

Install the nozzle after the accordian part of the stock intake tube right before the throttle body.

A far as the fuel, you can get a T and tap in to the fuel line between fuel filter and fuel rail, I got a fitting and taped in to the fuel pressure relief valve on top of the fuel filter.

Your stock fuel pump is fine, some kits have a pressure fuel pressure sensor that senses the fuel pressure and, if the pressure is not correct it will not allow the Nitrous solenoids to open

 

[NSX-Files]

Thanks CB169, and others. Those are the answers I was looking for! Hopefully, I will be on the laughing gas soon!

 

[CB169]

Thanks CB169, and others. Those are the answers I was looking for! Hopefully, I will be on the laughing gas soon!

No problem, you will love it and be faster than most of those 6-10k superchargers in the 1/4

 

[NSX-Files]

No problem, you will love it and be faster than most of those 6-10k superchargers in the 1/4

I'm sure I will love it. I just wanted a little "pick me up" and I already had the kit sitting around in my garage collecting dust. May as well put it to use. :smile:

 

[NetViper]

David are you going to need a rematch after the NOS? :biggrin: Let me know if you want some help installing it.

 

[RedlineRex]

i'm not sure if you are using the stock airbox setup. if you are running an aftermarket setup with a cone filter, you may want to look into using the ZEX Amplifier filter. you can install your fogger directly into the head of the filter and no permanent holes in your stock setup are required. just a thought.

 

[NSX-Files]

i'm not sure if you are using the stock airbox setup. if you are running an aftermarket setup with a cone filter, you may want to look into using the ZEX Amplifier filter. you can install your fogger directly into the head of the filter and no permanent holes in your stock setup are required. just a thought.

Stock Airbox.

 

[CB169]

i'm not sure if you are using the stock airbox setup. if you are running an aftermarket setup with a cone filter, you may want to look into using the ZEX Amplifier filter. you can install your fogger directly into the head of the filter and no permanent holes in your stock setup are required. just a thought.

I think those filters are for a dry nitrous set up

 

[CB169]

stock air box with a drop in filter is the best way to go, I made 270whp in my 3.0

 

[KooLaid]

What EXACTLY does that purple Zex box do? What components would I need to purchase to build an equivalent if I were to go with another brand?

Zex's website is crap. I can't find any good information there what so ever.

 

[ScienceofSpeed]

The ECU is supplied with the factory EPROM. I would install this back into the ECU (the ECU is socketed).

For fuel supply, this replacement banjo bolt (part no enpp-442) will work fine. It provides a female 1/8 NPT threaded hole right on the fuel filter.

http://www.scienceofspeed.com/produ...ducts/NSX/ScienceofSpeed/gauge_fitting_parts/

The compression numbers are within factory range, but a little on the low side. They are not low enough to be too concerned, but you should make sure they were done with the throttle body cracked when the engine was spun (make sure to always cut fuel supply as well - pulling the fuel pump fuse is a good idea). That accounts for around a 10% reduction in compression.

cheers,
-- Chris

 

[NSX-Files]

What EXACTLY does that purple Zex box do? What components would I need to purchase to build an equivalent if I were to go with another brand?

Zex's website is crap. I can't find any good information there what so ever.

The best source of info is the instruction manual for the kit you're considering. Zex website has the instruction in pdf format.

The purple box contains the brain, fuel and NOS inlets and outlets, and internal solenoids for fuel and NOS. The brain detects throttle position sensor voltage and triggers the solenoids to open and close the fuel and NOS lines only when you are at wide open throttle. I think it also detects NOS bottle pressure and varies the fuel opening to match.

I don't think any other mfr. has an equivalent to the purple box. It is basically an all-in-one box whereas the other mfrs. use separate components.

 

[KooLaid]

That sounds REALLY nice. Especially as a standard good all around kit. But it sounds like a PITA if you wanted to get more advanced with your NOS and add more goodies.

 

[BadCarma]

You still need help? I have been MIA for far to long. I have a shitload of folks with many installs to help with all over the place not just trampabay and I am helping folks in order I discover their messages and severity of any problems.I charge nothing for 3 hour phone support, will even provide free phone support on installs on any x , if you want me to install I have a vast prep list for the engine. just ask and it will not be free just perfect

best regards david