fuel system upgrades/NOS dry kit for a newbie

[tacodog]

Hello everyone,

I am a new member to stangnet, and fairly new to the mustang crowd. I have done some searching so bear with me on some of this stuff. I just want to clarify some of this, before i get my car together and have it run like a bag of you know what...

The skinny: I recently bought an NOS dry kit for my car, which currently has 100 horse jets in it....the only thing it was missing was a fuel press safety switch which i now have. I want to upgrade the fuel system in the car before i start using the kit, seems like its time soon anyways. Before i get the main point, just a quick blurb on the car so you know what im working with;

k/n cai
*new explorer intake
*new crane/svo 1.72 roller rockers
msd cap/rotor/wires
initial timing is currently at 16 degrees, car runs on 93..best i can get in town
deleted a/c and smog equipment
other than that, basically stock higher mileage 5.0L
factory headers, 2-1/2 o/r h-pipe of unknown make
flowmaster 40's
king cobra clutch
stock gears....hopefully making there way for 3.73's soon

So right now i am working on getting the intake intalled, along with the roller rockers. I am working really hard to find a set of gt40p's right now before i get everything together, either way i don't think it would affect the injector choice too much, it would just be nice since im this far. So from what i gather, most guys go with 24's with a mild head/intake swap. I am staying with the factory cam, since i got the 1.72's

Would that be sufficient for the extra 100 horsies the car will see at the track? (OR don't flame me too hard, the 150 jets it came with also, it would be a good excuse to build up a little 306....)

Should i step up to 30# injectors, or will the car be a pig the rest of the time around town off the bottle?

Also anyone with dry kits, what timing are you at, how much giggle juice are you using, and what heat range plugs are you using, how is it holding up?

I was thinking, backing off the timing 2 degrees, and i bought some ngk's which were 1 heat range lower than factory (hopefully that cuts it. I also went and bought msd's digital window switch for some added insurance, as the kit will be run off a w.o.t micro switch. Any help would be much appreciated......and if you've read this far, sorry for all that!

Aaron

 

[Grn92LX]

1-2 heat ranges colder gapped around .030-.032". Initial timing should be around 8-10* max for safety. 24's should be ok. Get a 255 HIGH PRESSURE pump and put a new fuel filter in while you're there.

If I remember, you'll have an activation switch inside the car that powers the WOT switch, then that powers the relay which in turn powers the solenoids.

 

[revhead347]

I think I'm the only NOS dry kit guy on here, and I spray about 150. Don't let anyone bull**** you, that is the best kit ever made for a Mustang. However, the NOS solenoids are not very good quality. You might want to step up to a better quality solenoid later on, but not necessary now. The size of the injector really doesn't make a whole lot of difference with the dry kit. For that engine, a 255lph in tank pump is fine. If you go to the 150 shot, you might have to put a Vortech T-Rex inline pump in. You can pick up a used one on ebay for about $100. A fuel pressure gauge is a really nice thing to have, especially for the 150 shot. The fuel pressure safety switch maxes out it's adjustment at 65psi, and you need about 100psi to spray 150. If you have a fuel pressure gauge, then just check it when you spray. As long as the fuel pressure pegs and stays up there, then your fuel system is adequate.

Wiring basics: The kit should come with two nitrous solenoids, a fuel pressure safety switch, a fuel pressure boost solenoid, and a Wide Open throttle switch. The WOT switch attaches to the throttle body itself. The arm switch actuates the relay, the ground side of the relay goes through the WOT switch. The first solenoid is grounded normally, the seconds solenoid is grounded through the fuel pressure safety switch. When arm switch is on, and the WOT is activated, the relay sends power to both solenoids. The first solenoid will open immediately sending nitrous to the 2nd nitrous solenoid, and the fuel pressure booster solenoid. When the fuel pressure reaches 65 psi, the second solenoid gets grounded, and allows nitrous into the engine.

You can actually modify the kit up to a 225 shot with a little ethnic engineering. It's hard to say what my timing numbers are because I have a chip, and that effects the total timing differently than a stock tune. I run 13 degrees of base timing, and pull 5 degrees out on the bottle. The general rule is 2 degrees for every 50hp on the bottle. I would recommend pulling 6 degrees of timing out until you can get the car on a dyno with a wideband to make sure it's running safe.

Kurt

 

[Tanus]

what id do; 24lbs, back timming to 10 or 12, 255lph, swap wot switch to a push botton(momentary switch)

Id also add a fuel solenoid to make it a wet kit.

if you plan to spray it alot a jacobs nos mastermind is definatly a good idea, 20lbs bottle will also give you more consistant pressure, therefore more consistant shots.

my old setup was a pecied together wet kit, 150hp jets, 20lbs bottle, jacobs MM, ran 255 in-tank and in-line. ran like tons of bottles through it, never had a problem, motor is like 8 years old now, still going strong

 

[revhead347]

Even if you have a momentary switch, it's a good idea to have a WOT switch, in case you **** yourself, let off the gas, and still hold the momentary switch. The Jacob's is really overkill. There are a lot better places to spend if money is tight.

Kurt

 

[Tanus]

well for a auto car a think the wot switch would be fine, but a stick Id go with a push botton, and yeah could wire a wot and momentary switch together

the jacobs is kinda overkill, but it does let you set motor to run best N/A then pull timming when you spray it. It has alot of safty features too, and I think the best feature it allows shot to come in slowly, instead of 150hp all of a sudden its 50hp, then half second later hits full 150hp.

 

[revhead347]

Not sure that Jacobs would work with a dry kit. You can pull timing automatically with a basic MSD kit. But that costs money. It's nice to keep things simple for new guys.

Kurt

 

[Tanus]

it'd work, wireing on a dry kit and wet kit are identical, but yeah, definatly alot of sh-it to wire up

the problem with the dry kit IMO, is when it jumps the pressure real high, most injectors actually work worse at 65 psi than 45 psi, the gen 1 and 2 especially, gen 3 can handle high psi. So if you do go dry set-up, get the gen 3 injectors, I have em, they definaly are noticably better on the low end.

 

[tacodog]

Thanks for the replies all! I didn't expect this much good information this quick. Im not too familiar with the jacobs but is sounds cool...and pricey. The budget thing did come in to play, which is why i got the window switch. Im thinking i will just have it in series with the w.o.t switch, unless maybe there's a better spot for it?

Also Ive heard alot of different interpretation on safe rpms for usage. The few local guys ive talked to are running wet kits, and from what they were saying, need 2500-3000rpms for enough intake velocity to safely pull the mixture into the cylinders. Is that the same for dry kits as a rule of thumb also, or is anyone spraying at less rpm than that. Would that be too much load on the engine below that rpm range? I was going to set my window switch from 2500- to around 500 under redline. Does anyone see me running into trouble there?

In my original post, what i meant to say about my timing arangement, was to pull 2 degrees, from the factory 10, but it came out sounding like i was going to run it at 14....Doh. Sounds like 8-10's pretty safe from what you guys are thinking, or atleast until i can get a tune to see what the cars doing.

Also the fuel pressure safety switch i bought is only adjustable from 35-70 psi if i remember correctly....maybe throwing in the 150 jets would be a bad idea, or get a different switch

When i bought the kit, it also came with an NOS in line fuel pump. Would that be similar to the t-rex (i haven't even looked at my inline to see the specs on it, and how the t-rex differs from it output wise)Should i even bother putting it on if i only run the 100 jets in it?

Revhead: about the injectors, this kit has been laying around for a while unused, would it be a good idea to go through the solinoids...i think a guy can get kits for them with new o rings, and orfices....

Tanus: When you were talking about gen 3 injectors, are those the 4 pintle design? Hopefully so, i found a guy selling reconditioned 4 pintle 24's for $140 locally, otherwise they are $300 at the best priced shop closest to me.

Also with running 24's, can i just get a sample tube to modify my factory maf, as its a 70mm, don't really want to fork out the cash for a new one the same size!! Who sells them, as i have not seen them anywhere i shop.

lastly,

Would it be worth my time to get an adjustable fuel reg?? just thinking while im firing out the questions, i might as well throw that out there too.

Thanks in advance!

Aaron

 

[tacodog]

One last thing...I forgot to mention the car is a 94, so im stuck with the hypertectic slugs....time bomb?....just thought id mention that.

 

[revhead347]

Ok, well that's a lot of questions to answer. Firstly, don't worry about the pistons, those hypereutetics are actually a lot stronger than most people think. They are actually stronger than the forged pistons Ford put in the Mustang in previous years. Hypereutectic pistons don't expand as much as forged pistons at higher temperatures. However, they are more brittle, and are more apt to shatter. Safe nitrous usage should not even be an issue with stock pistons.

I would go ahead and get another MAF, it's the cheaper option. The stock one is 70mm, but it is a little bit restrictive by design. It should be sufficient for the heads and intake you are using, but it will slow you down later on if you decide to do more mods. I've not heard many people have good luck with changing the sample tube.

An adjustable fuel pressure regulator is a good tool for tuning your engine, but it's not necessary for the nitrous system. You can tune that with the bypass jet.

I wouldn't mess with the solenoids. I've rebuilt NOS solenoids a bunch of times. The rebuild kit is expensive, and it doesn't last as long after it's been rebuilt. I would use them for as long as you can, and test them regularly to make sure they are both opening and closing. If the second solenoid jams open, you won't notice it. The redundancy of the two solenoid system, makes the kit pretty safe against jams. Save your money from the rebuild kits towards better quality NX solenoids.

I wouldn't worry about the fuel pressure safety switch right now. You can set it for the 100 shot for now. Once you get some more experience with the 100 shot you will figure out what you want to do next.

The inline nitrous pump is probably the same thing as the T-Rex. You shouldn't even need it on a stock engine, but it won't hurt to install it, since you already have it.

There really isn't too much danger of the mixture exploding on a dry kit. However, it's best to hold out on the spray till about 3000rpms due to piston speed. There really isn't any advantage to spraying below 3000rpms anyway. A window switch is a great investment, and it is double protection against missed shifts. Nothing worse than missing a shift, and hitting the rev limiter with the nitrous on. Just set it right above your shift point. Normally you shift a stock Mustang at 5500rpms, so just set it at 5600 for now. It will shut it off before the fuel cut at 5950.

Kurt

 

[Tanus]

Tanus: When you were talking about gen 3 injectors, are those the 4 pintle design? Hopefully so, i found a guy selling reconditioned 4 pintle 24's for $140 locally, otherwise they are $300 at the best priced shop closest to me.


Aaron

the gen 3s are the skinny design ones, good upgrade from the gen 1 or 2. definatly put on the nos pump. Id never spray under 3k rpms, I had the jacobs set to only allow it to pray from 3k to 6k,(so even if I happened to hit it to early or hold to long it wouldnt spray). Id shift at 6,800.

Ok, well that's a lot of questions to answer. Firstly, don't worry about the pistons, those hypereutetics are actually a lot stronger than most people think. They are actually stronger than the forged pistons Ford put in the Mustang in previous years. Hypereutectic pistons don't expand as much as forged pistons at higher temperatures. However, they are more brittle, and are more apt to shatter. Safe nitrous usage should not even be an issue with stock pistons.


Kurt

+1, hypertectics just dont handle detenation as well, run a safe tune and you'll be good

 

[revhead347]

If you don't have the money to put the car on dyno, just keep a little on the rich side and more conservative on the timing, and you'll be ok.

Kurt

 

[dirtyboy069]

I'm running the NX valves on my NOS kit works like a champ I have ran 4 10lb bottles and never had a problem its always best to upgrade when you can afford it because let me tell you nitrous can do some real damage if everything isn't working properly

 

[revhead347]

I switched to NX solenoids a few years ago. I just got tired of rebuilding NOS solenoids. The best part is, you can pick your favorite NOS solenoid, and use it for a purge. So, when you upgrade, you pay $200 for new solenoids, but you save $60 on a purge kit.

Kurt