Nitrous Questions

dbdragracing

dbdragracing

Member
Dec 1, 2004
397
2
18
#1
I have a 1989 Mustang GT with a T-5, Mac shorty headers, Mac o/r h-pipe, Flowmaster 40s and a cold air intake. I have a few friends running nitrous and have been impressed with the results. I was considering buying the Nitrous Express (NX) 20915 kit after a test I read in Muscle Mustangs and Fast Fords.

Do I want a dry or wet kit? Whats the difference? What do you think of NX kits?

Any help will be appreciated. Thanks.
 
#2
most people are going to tell you to go with the wet system, however I installed a dry NOS system on my 89 and I love it. With the dry system, only nitrous enters the air intake manifold, with the wet system gas is also sucked in the intake - at times and under certain conditions you can have detonation (if fuel puddles in the intake).

with the dry system extra fuel is added through the existing fuel injectors. Changing HP settings is a simple as removing the nitrous jet and replacing it with either larger or smaller - takes about 2 minutes.

I also have over 300,000 km on the original stock engine, and the engine is holding stong - even after many many many nitrous runs. I've had it on my car now for at least 5 years. I'm running the 125HP jet.

You might also want to pick up a bottle heater and blanket. You'll get more pressure in the nitrous tank if the bottle is warm. I took my original NOS heater off and replaced it with a dual heater. this allows the car to warm it up just like the NOS heater did, but more importantly it allows me to plug the blanket in household current - which heats the bottle much quicker and doesn't drain the car's battery. If you are interested I'll find the link.

I don't have much expeirence with the other kits, just NOS, but I imagine they are all pretty much similar.
 
#3
I run a wet kit and like it a lot. There are a couple of different type of wet kits.

Kit #1 - Has a nozzle that goes into the intake tract between the MAF and the TB.
Kit #2 - Has a plate with a spray bar that goes between the TB and the EGR spacer
Kit #3 - Has a plate with a spray bar that goes between the upper and lower intake manifolds.

The kit that I have is the 3rd one. The first two can exhibit the problems that Scott mentioned with puddling in the upper intake. Particularly if you use it to low in the RPM range. The upper intake flows air quiet nicely but fuel even atomized can be a little tricky when low in the rpm range.

The wet plate kit that goes between the upper and lower intakes eliminates the problem of fuel puddling. They are a little pricey but I really like mine. Mine is a Trickflow kit that is basically a rebadged NX kit. This is the kit that I have http://store.summitracing.com/partd...4294925239+4294839080+400098+115&autoview=sku
 
#4
Others have already told you about differences...I had a NOS dry kit on my old stang. I only ran it before the H/C/I, only shorties, catted x, flows and i think the stock 2.73 gears. I started out with the 50 or 75 shot, whatever was lowest. Then stepped it up to 100, and finally a 125. That 125 was wicked fast. Made 2nd gear feel like 1st, 3rd like 2nd, etc... through the stock AOD. Very simple to install as well. Took me maybe an hour or 2 at most. How the dry system worked was a vacuum tube plugs into the FPR and ads more fuel as it needs it. Oh, and make sure you retard your timing 2* per 50 shot. For example, a 150 shot would need 6* retard. This is just a general safe rule of thumb. I ran 10* timing with my 125 shot. Normally ran about 14-16*.
 
#8
My car is basically stock...it has a cold air intake, shorty headers, o/r h-pipe, Flowmaster 40s and a t-5 swap. What else do I need to upgrade to put a 100 shot of nitrous on my car (spark plugs, fuel pump, etc.). Thanks.
 
#9
I upgraded the fuel pump to a 255 lph pump. The stocker should provide enough fuel for a 100 shot but I didn't want to risk leaning the car out and putting a hole in a piston. My though is the bigger fuel pump is cheap insurance.

If you aren't getting any detonation then you can run the stock plugs but you will need to close the gap up to around .035" so that the increased cylinder pressures don't blow the spark out. What I would do is make a pass with the stock temp range plugs and as soon as you get onto return road shut it down and pull the plugs and check them. If you see little silver flecks on the porcelian that is a sign of detonation. If you timing is backed down 2* for every 50 hp of
N20 then you need one set colder plugs.
 
#13
So with a 100hp shot you would run 2 degrees less of base timing. 2 less than stock or 2 less than current (if advanced)? I run about 14 now, so if I went with N2O could I go with 12 degrees base or would I need to go to stock minus 2 = 8 degrees?

Reason i ask is that I would hate to comprimise the NA driving, its not like i am going to use the nitrous light to light!
 
#16
Like bluecoupe said its 2 degrees off of your timing with the SPOUT out. So if you run 14* with the SPOUT out then you would run 12* on spray. Personally I like to pull 2* per 50 hp of N2O so if it was a 100 shot then I would pull 4*. Then I will add a degree, make a pass and check the plugs. If all looks good then I add another degree and check again. I will only add up to 2* of timing back in. It is much easier to pull a little too much timing and add it back in then to not pull enough and hole a piston.

There are some ways to get around having to manually pull timing just for nitrous. Ignitions like the Digital 6 have a timing retard that can be hooked up to the nitrous solenoids and pulls your specified amount of timing when the solenoids are energized. Also you can run a flip chip with an NA tune and a nitrous tune. Both are alittle pricey and for the occasional dragstrip car probably overkill.
 
#18
the timing change depends drastically on your setup... i originally went with the 2* for every 50 shot and it wasnt close... it was too rich, i ended up with 3 * for my 125 shot in order to make the nitrous/fuel mix right...but i also run compucar wet kit... every kit and engine combo is going to be a little different, i definately recommend getting it tuned on a dyno so you can get air fuel read out if your going to spray a significant amount, the jets that they tell you to run are just a guide line, not exact so you always have the potential to run lean unless you get it tuned... but i always like to play it on the safe side.. hope that may help

jim
 
#19
allballsmustang said:
the timing change depends drastically on your setup... i originally went with the 2* for every 50 shot and it wasnt close... it was too rich, i ended up with 3 * for my 125 shot in order to make the nitrous/fuel mix right...but i also run compucar wet kit... every kit and engine combo is going to be a little different, i definately recommend getting it tuned on a dyno so you can get air fuel read out if your going to spray a significant amount, the jets that they tell you to run are just a guide line, not exact so you always have the potential to run lean unless you get it tuned... but i always like to play it on the safe side.. hope that may help

jim
Click to expand...

I am the same way, I would rather double check things and be sure that when I run the car its going to be safe. Being that I have no experiance with
N2O I appreciate you guys lending your knowledge:nice:

Basicly you have to retard timing to prevent detenation, how much depends on your set up.
 
#20
Ive decided that Im going to run a wet nitrous kit, but which one is the best? I've been looking at:

-Zex
-Nitrous Express (NX) - leaning toward this kit because they are running a special including a purge kit and nitrous gauge!
-Compucar

Thanks for any help.
 
You must log in or register to reply here.

Similar threads

TTSaleen
Need some camshaft guru advice on power loss from supercharger to nitrous
Replies
18
Views
554
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
revhead347
revhead347
M
Engine Unexplainable Exhaust Pop and Gurgle
Replies
12
Views
457
Fox 5.0 Mustang Tech
Noobz347
Noobz347
A
Procharger install/prep questions
Replies
2
Views
310
SN95 4.6L Mustang Tech
Noobz347
Noobz347
E
New Member with 91 foxbody
Replies
9
Views
375
The Welcome Wagon
EricMac13
E
squeak93
Tuners come on inside
Replies
1
Views
211
SVT Tech Forum
squeak93
squeak93
Top Bottom
Back
Forums
Menu