Nitrous and a 4-spd!!??

[Nitrous340dart]

Hey guys,
I'm new to this forum and to the happy juice. I am building a 67 Dodge dart with a 340 bored .045 over, custom Venolia pistons, custom Cam-Motion solid roller (.260ish duration and .640ish lift :D), Eagle rods, Mopar crank, and ported Edelbrock heads with most likely a Indy single plane. The car is caged and once the 4-spd conversion is complete it should weigh in at around 3200-3300lbs. I have been looking at the NX Gemeni Twin stg 6 50-300 kit.
Its mini tubbed and will run about a 10.5-12" slick most of the time with a 3.91 suregrip rear (we'll see how long that last...might spool it).

I know the fundamentals of Nitrous, but i had a few questions of applying it to the ground.

1.) Should i pick a carb based on my motors N/A size and HP, or should i pick a carb based on the total HP from the motor with N02? ( i was thinking of a 825 Mighty demon

2.) When are most people hitting the juice with a manual car? Off the line and how much through the rpm range?

3.) Are Nitrous controllers worth it and which one offer the most tunability?

4.) Do most people just trigger it on a micro switch, micro switch and button, or just a button? I was thinking of the micro switch and button so i can "use it, if necessary".

Thanks for everyone help.

Ben W.

[flames4me]

1. pick the carb right for your N/A setup.

2. I a pretty sure you have a manual trans 4-speed, so I will assume this in my responces. For you with a pretty torquey motor you will more then likely hit it right after shifing into 2nd gear and hold it down until the race is over (exept during shifts)... this is all depending on how much traction you get off the line, if setup correctly you will be able to enguage the nitrous off the line.

3. no, with nitrous controllers you get what you pay for. find your budget and go from there, the cheapest is around $100 for a ramp up speed only while the best is around $550 for timed delay, initial shot size, ending shot size, ramp speed, pulse frequency, basically total control of your nitrous (this is the progressive controller that I am using and I love it).

4. This is all personal preferance and depends on what shot you are running, you can run a 50shot with just a button and don't really even need a WOT switch. or for higher level nitrous shots you can really get into the safety devices to allow total control and have extremly consistant runs. Many people run a WOT switch and an RPM window switch and that is it. There are so many ways of wiring up your enguagement it is hard to find the way that will benefit you the most, I am sure when we get to know your setup more then we can help you choose the correct enguagement for you.

welcome to the forum! what shot size are you planning on? have any NA 1/4 mile numbers? sounds like you have a very nice old school muscle car setup there, it is hard to find people who build up older cars with new(er) technology like nitrous and other electronics.

[Nitrous340dart]

I plan on starting off with a 150 shot then maybe top out at 300. The cam and piston where built to work with a 400 shot, but my car is just 6 point caged with 2-piece "mono leaf" and Cal-track bars from Calvert. I would probably want a better chassis before i go too big.
I'm running the A-833 cast iron manual. No one in my town really has anything on Nitrous so I'm glad i can ask all my question here before i blow something up!

[flames4me]

lol, dont want to blow up that nice engine of yours!

One thing that you dont want to overlook with nitrous is your fuel pump, do you know if your fuel pump can keep up with that much nitrous?

you seem like you are the kind of person that likes to do things right the first time and not try and "bargain" your way through things. I am just going to make a few suggestions or rather a list of all possible things that can help you get the nitrous system that you desire. If you have any questions on anything please ask otherwise general inforamation and prices are readily available on the internet...

starting minor and workinng to more in-depth:

WOT switch,
fuel pressure safety switch (FPSS),
fuel filter and nitrous filter,
wiring up a 1st gear lockout,
RPM window switch (highly recomended),
progressive controller (with this you should also get a secondairy nitrous solonoid for if the primary sticks open),
Complete stand alone fuel system (for if you have doubts about your current fuel pump)... benefits of this includes possiblitys of running any octane gas you want or even alcohol for your nitrous system alone,
possibly direct port nitrous injection?

sorry to sound like a salesman but I am just not sure what you already know or how set you are on the plate kit you have picked out. Just with 150-300shot I don't want to see you under-build your system and have something go wrong and ruin your engine b/c of nitrous. Anything above 100shot you should start to buy safety devices that your kit may not have included.

[Nitrous340dart]

I have a Holley Black pump for the motor and was thinking about running another black for the Nitrous fuel system, i might run a BG pump though, i haven't boughten one yet. But both lines were going to be 3/8", coming from one 20g fuel cell in the back, well i bought the fuel cell and installed it i thought i would drive the car more often. But since the nitrous build i dont plan on driving it too much, so there will probably always be 110 race gas in it.

I did plan on running a WOT switch and a button. But ready through the FAQ here i am deff running a FPSS and possibly a window switch.
I was also thinking of running the MSD digital 6 box, cause i already have the MSD dist. and coil. But are there better ign boxes suited for nitrous? Or should i run a MSD box and then use some other stand alone timing retarder?

I can always use as much info as possible, you can never know enough and there is always someone out there that know more than you!

[Nitrous340dart]

What is a first gear lock out? I thought that if i could set up my chassis good enough i might be able to hit it off the line.

[flames4me]

yea, if you can setup your car to take a shot right off the line, go for it! otherwise, a first gear lockout is a WOT switch mounted by the shifter to open a conection when the shifter assembly is in the 1st gear position, the close the connection once you shift out of 1st gear... simple add-on in your wiring.

MSD makes some really retard boxes. They have a fw differant options, one you can adjust the reatard by a knob in the cab. This can be useful if you want to tune your car to ake maximum HP depending on octane of gas in your tank, shot size, etc. The other couple options are pre-set retard boxes, I am not as familiar with how these work, but they are not as adjustable as the knob style but they can be wired up to only work when the nitrous is enguaged and return back to previous timing when you let off the switch giving maximum N/A and nitrous hp.

and yes, the MSD digital 6-AL is a popular ignition box for use with nitrous.