Wet Nitrous kit questions
 

If you use a wet nitrous kit how does the tuning work? Tuning is like black magic to me. I know the general concept but if you tune for nitrous how does the car run when you're not using the gas? Does it run rich all the time?, do the colder sparkplugs foul up quicker? I'm looking at increasing power while keeping daily driver reliability and the cheapest way seems to be nitrous.

Now to brands. I know everyone has their favorite brand, but which one offers the best bang for the buck? Ease of installation is not an issue, I know my way around fabricating. I just want a system as automated as possible. Also, my car has traction issues when launching at the strip since suspension is set up for road racing, can the nitrous be programmed to come in at second gear instead of at launch? (Car is manual if that matters)

And the most important question of all. On a stock 4.6 engine how much nitrous can you safely run assuming 93 octane gas, which is what I run on the track.

Sorry for all the questions, but with suspension mods nearly done it's time to start looking at the engine.

nice quick comparison article: http://www.americanmuscle.com/differ...y-nitrous.html

A nitrous tune for daily driving will be a compromise on daily driving performance. But nitrous is really only a track power adder and not something you drive around with all the time. If you leave the bottle in the car, pressurized, you are putting a constant 900lbs of pressure (at least with a full bottle) against the solenoid. Eventually the solenoid wears out.

So you get a specific nitrous tune and when you get to the track you program the car, turn the bottle on, turn on the heater to keep the pressure up and race. At the end of the day, turn the bottle and heater off, put your street tune back on and drive home. Fill the bottle for the next trip.

And running nitrous all the time gets expensive. The cheapest I ever found it years ago was $4 a pound. Running a 75 shot I could get 10 passes at the track and then had a hard time keeping the pressure up as the bottle got low.

I prefer a wet kit for the Mustang. With a dry kit you are relying on the computer to recognize that you are spraying and then add fuel through your injectors. A lot of variables leaving a lot of things to chance that you will have the fuel there and not run lean when you spray.

Also, get a window switch! I had the Zex kit on my car, and the Zex Nitrous Management Unit (NMU) is supposed to learn when you are at wide open throttle. I did all the steps and everything said it knew WOT. I was lining up one night and had the system armed, brought the tach up to 1,800 rpm for the launch and the NMU said "good enough, call that WOT" and fired off. I was lucky to get off the throttle quick enough to avoid any problems, although I had a red light since the added power launched me through the beams!

After that I installed a window switch. The window switch sets your nitrous open window based upon RPM. I had it set so that the NMU couldn't see the RPM until it reached 2,300 rpm; and then it shut the window just below red line as well. You don't want to spray too low or too high in the RPM band.

Thanks for the replies and sorry I took so long to respond. Was researching the issue. I know I can run a street tune and just load the nitrous tune at the track, but the colder plugs have to be on all the time. Will they foul up or hurt performance? The window switch is definitely a must as is a wet kit, but I'm still confronted by traction issues, so how do I tell the nitrous to not come on in first gear, a two stage switch? And whats a safe shot for a stock bottom end running 93+ octane?

I didn't use a colder plug on my 2006, but that was the 4.0 and Lidio said it wasn't necessary on that engine.

Some window switches you can set up so that it doesn't spray until second gear. I never had traction problems though. With the window switch set up to open at 2,300 rpm the car was already moving - about the 60' mark you could see the nitrous hit though when the front raised up. But never lost traction.

Thanks, now I've got to choose a brand, I'm leaning towards Nitrous Express or Zex, since those seem to have kits specifically for the 4.6. Looked at NOS but they didn't seem to have a dedicated kit. Any other brands I should look at? Ease of installation and reliability are top concerns.

You can run the stock plugs with a 75 shot. You'll be just fine.

If you have a tuner, you can pull two degrees of timing out of the tune. It's what I did for a few years and it worked great.

Lastly, do yourself a favor and get some track tires/wheels. I almost put my freshly custom painted car into the wall because I was racing on street tires. You need a drag radial.

I have a set in my shop I'm not using. MT ET streets on a17x8 rim. I 60' 1.49 on them. I don't know how much they would be or what shipping would be but I'll look into it if interested.

If you do not spray off of the line you'll be disappointed. The first 300' is where your car will spend more time than any other section of the track. You need spray off of the line.

What size are the MT's?

26.5x11.5x17