Nitrous on a 340 100 shot

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nfhDODGEnfh

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I'm planning on adding a 100 shot of nitrous to my street car. Its a 69 dart 340 and has a mild cam, intake, headers and msd ignition. I'll be tossing out the mechanical fuel pump for an electric one that is 7psi and can handle 60gph at that rating. Looking for any input if that will be enough constant fuel supply for my needs? (It's all 3/8 fuel line) Plan on using a 100 micron pre filter and a 10 micron post filter then teeing off the fuel line and hooking it to the solenoid. They are both earls reusable filters and should handle the gph. Another question I have is about the spark plugs, do I need to get colder plugs when I'm just spraying 100 shot? If so how much colder and do I need to change the Gap? Seems like I could just throw it on and things would be fine, any advice would be greatly appreciated. I'm just looking to get a bit more thrill when I stab the throttle.
 
For a 100 shot you could proabally just throw it on and be fine
Whats your total timming ?
You wanted it tuned to 9th degree before you spray it
You want a saftey so if the gas solenoid does not open the spray solenoid doesn't spray
Low fuel pressure saftey wouldn't be a bad idea
stock plugs and gap should be fine foe 100 hp
I would start 2 degrees retard from best tune on pump gas read the plugs
Race fuel you dont need to retard timming but i would to start
Less is more sneak up on where you want to be
You will love the thrill best part is its only on when you want
 
For a 100 shot you could proabally just throw it on and be fine
Whats your total timming ?
You wanted it tuned to 9th degree before you spray it
You want a saftey so if the gas solenoid does not open the spray solenoid doesn't spray
Low fuel pressure saftey wouldn't be a bad idea
stock plugs and gap should be fine foe 100 hp
I would start 2 degrees retard from best tune on pump gas read the plugs
Race fuel you dont need to retard timming but i would to start
Less is more sneak up on where you want to be
You will love the thrill best part is its only on when you want
I will wire both solenoids to the same relay so they work in tandem. Currently I'm at 35 degrees timing and it runs pretty dang good. Are you supposed to pull 4 degrees for 100 shot? That was my plan anyways to dial it back to 31* when I have the bottle on. I'll just make a refence mark so I can switch between them somewhat simply
 
I will wire both solenoids to the same relay so they work in tandem. Currently I'm at 35 degrees timing and it runs pretty dang good. Are you supposed to pull 4 degrees for 100 shot? That was my plan anyways to dial it back to 31* when I have the bottle on. I'll just make a refence mark so I can switch between them somewhat simply
I would start@2 degrees on 94 pump sneak up on it
Many moons ago i had the nitrous solenoid fail to open it bogged as it still got the gas i had no safeguards young and foolish
Even wired to the same relay the can still stick
no gas no spray
 
I would start@2 degrees on 94 pump sneak up on it
Many moons ago i had the nitrous solenoid fail to open it bogged as it still got the gas i had no safeguards young and foolish
Even wired to the same relay the can still stick
no gas no spray
What is your recommend solution for ensuring the solenoids both work?
 
If you run 7 psi fuel to the solenoid, the likelyhood of the tune up for juice will be horribly FAT. That is not a good approach. Fat kills parts too.
 
7psi is the maximum pump output. What would you recommend then? If 7 is too fat and will break parts. Regulating it down to 5 at the solenoid? I'm asking questions because I'm learning about nitrous and looking for advice
 
What kit? Look at the instructions would be my first suggestion. There will be recommendations on fuel pressure and jet sizing.

Just a baseline to consider from running this stuff off and on for 40 years. If the fuel jet is larger than the nitrous jet, it's most likely a FAT tuneup. It can be cleaned up a lot.

An AFR meter helps a lot. Have the tune up on the engine great, then add juice. Tune juice to the same non juice max MPH AFR if running at the track. Runs best MPH at 12.2 on motor, run the juice at 12.2 as well.
 
It would be a 100 shot of nitrous from a nitrous express kit ML1000, I assume they will tell me what jets to use for the 100 shot as it's the lowest setting on the kit and the one i would use. The fuel pump in question could be regulated down easily if that's necessary. I have never run nitrous before and am considering it. Just looking for suggestions and info from people who may have already done this or experience as I have not yet. I never considered 7psi being way to FAT as most carbs are good for 5-7 psi. I figured it would be right around perfect to just drop it on and try. Did you have a starting point suggestion for regulated fuel pressure at the solenoid? Wpuld you regulate the whole carb down aswell or just the solenoid? I plan on giving it a try and watching the spark plugs to see how it reacts.
 
It would be a 100 shot of nitrous from a nitrous express kit ML1000, I assume they will tell me what jets to use for the 100 shot as it's the lowest setting on the kit and the one i would use. The fuel pump in question could be regulated down easily if that's necessary. I have never run nitrous before and am considering it. Just looking for suggestions and info from people who may have already done this or experience as I have not yet. I never considered 7psi being way to FAT as most carbs are good for 5-7 psi. I figured it would be right around perfect to just drop it on and try. Did you have a starting point suggestion for regulated fuel pressure at the solenoid? Wpuld you regulate the whole carb down aswell or just the solenoid? I plan on giving it a try and watching the spark plugs to see how it reacts.

Not close to what was written. My comments ONLY have to do with the juice kit. The carb may be just fine at 7 psi. Most juice kits I messed with were in the 5-6 range.

If you don't have the kit and instructions, you are asking questions that are in those instructions. There will be a tune up. A regulator on the fuel side of your kit will likely be necessary. I bet the instructions are online. Simple enough to see what is suggested.
 
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Not close to what was written. My comments ONLY have to do with the juice kit. The carb may be just fine at 7 psi.

If you don't have the kit and instructions, you are asking questions that are in those instructions. There will be a tune up. A regulator on the fuel side of your kit will likely be necessary. I bet the instructions are online. Simple enough to see what is suggested.
Thanks for your advice and input I'll download the installation instructions and see what they say.
 
Was shooting the **** with a friend that runs a bunch of NE stuff. They usually want around 8 psi, so your fuel pump isn't going to cut it from the suppliers perspective.
 
Was shooting the **** with a friend that runs a bunch of NE stuff. They usually want around 8 psi, so your fuel pump isn't going to cut it from the suppliers perspective.
Thanks! Yeah I read that in the instructions after I downloaded them on your advice. So I'll get a pump that can go to 10psi as that's what the 250 shot requires and the 100 does need 8. I'll also get a fuel pressure switch to run in an sttempt to safety the system somewhat.
 
6 to 6.5 psi is about what it should be with the solenoid open running
 
6 to 6.5 psi is about what it should be with the solenoid open running
Just to recap the whole install of the nitrous express ml-1000 nitrous kit for anyone that follows this thread for info and in my position if never running nitrous before. One important first note was a great idea from crackedback READ THE INSTRUCTIONS FIRST!! ( i downloaded them before purchasing so I had some idea of that parts i would need to make it work and the pressures the system requires) The install went well but be aware the kit requires 8psi fuel pressure so I added a 14psi constant flow pump with 100gph at 9psi so it should have more than enough to bump the power up in future if I want. But I had to add a 3/8 return line into my tank for the pressure regulator. That required getting a friend to tig weld the new return line into my sending unit as I already had 3/8 line for feeding the old pump. It could be brazed if you have the capability but my friend was down the road with tig. The fuel pump i hooked up with an oil pressure saftey switch that is bypassed when you turn on the starter to prime the system. I put a fuel pressure gauge just after the regulator and added a 3/8 brass t so that I could have a mr gasket regulator to feed the carbs as 8psi is too much for a carb. I put all that just behind the alternator where the old fuel pump was and I mounted it to the fuel pump block off plate. Also I added a fuel pressure switch after the regulator to cut the ground off for the nitrous and fuel solenoid circuit if the pressure goes to low, it won't allow me to spray nitrous below 7psi at this time but its adjustable. I also added an afr gauge to monitor things on and off nitrous and help tune for peak power in both settings. I had all that hooked up and got the nitrous kit installed, had the bottle filled and checked for leaks, that went well but the pressure was a bit low.l at 700psi. I rnded up having to get a nitrous bottle blanket (I got the one with pressure regulator) nitrous express wants 1000psi at the solenoid so I will set the blanket regulator for a range just above and below that. Also the nitrous plate moved my stock air cleaner to high so I am waiting for a 1" drop 13" air cleaner base from Mancini racing as it works with the stock silenced cleaner lid. I should have that next week and them I'll dial the timing back to 33 degrees, clean up my spark plugs and take it for a test hit!!! I'll let you now how that goes and add some pics if anyone is interested.
 
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Just to recap the whole install of the nitrous express ml-1000 nitrous kit for anyone that follows this thread for info and in my position if never running nitrous before. One important first note was a great idea from crackedback READ THE INSTRUCTIONS FIRST!! ( i downloaded them before purchasing so I had some idea of that parts i would need to make it work and the pressures the system requires) The install went well but be aware the kit requires 8psi fuel pressure so I added a 14psi constant flow pump with 100gph at 9psi so it should have more than enough to bump the power up in future if I want. But I had to add a 3/8 return line into my tank for the pressure regulator. That required getting a friend to tig weld the new return line into my sending unit as I already had 3/8 line for feeding the old pump. It could be brazed if you have the capability but my friend was down the road with tig. The fuel pump i hooked up with an oil pressure saftey switch that is bypassed when you turn on the starter to prime the system. I put a fuel pressure gauge just after the regulator and added a 3/8 brass t so that I could have a mr gasket regulator to feed the carbs as 8psi is too much for a carb. I put all that just behind the alternator where the old fuel pump was and I mounted it to the fuel pump block off plate. Also I added a fuel pressure switch after the regulator to cut the ground off for the nitrous and fuel solenoid circuit if the pressure goes to low, it won't allow me to spray nitrous below 7psi at this time but its adjustable. I also added an afr gauge to monitor things on and off nitrous and help tune for peak power in both settings. I had all that hooked up and got the nitrous kit installed, had the bottle filled and checked for leaks, that went well but the pressure was a bit low.l at 700psi. I rnded up having to get a nitrous bottle blanket (I got the one with pressure regulator) nitrous express wants 1000psi at the solenoid so I will set the blanket regulator for a range just above and below that. Also the nitrous plate moved my stock air cleaner to high so I am waiting for a 1" drop 13" air cleaner base from Mancini racing as it works with the stock silenced cleaner lid. I should have that next week and them I'll dial the timing back to 33 degrees, clean up my spark plugs and take it for a test hit!!! I'll let you now how that goes and add some pics if anyone is interested.
Here's a few pics of the install. Still need to clean up the wires a bit but I ran out of wire loom, and waiting for the drop air cleaner base.

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Here's a few pics of the install. Still need to clean up the wires a bit but I ran out of wire loom, and waiting for the drop air cleaner base.

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1 tune the setup to the 9th degree before you spray it
2 get a bottle heater
3 enjoy your big block torque at the press of a switch
 
1 tune the setup to the 9th degree before you spray it
2 get a bottle heater
3 enjoy your big block torque at the press of a switch
Thanks for your advice aswell! It's great to have a community with help and support! I did get a bottle warmer already as the ml1000 kit wants 100psi of pressure so I made sure it is heat regulated. Also a shout out to Inertia the member on here as I did the install at his shop with his son!! I'll post the results when I get out and spray it.
 
Got the timing dialed back 2 degrees and new spark plugs 2 heat ranges cooler. The 100hp hit was awesome when going wide open at 3000rpm in secound it shredded the tires for a sec and took off like it was in first gear. Well worth the price of admission and my afr gauge was about 12.2 for wide open throttle with and without nitrous. I didn't hear any detonation so maybe ill slowly try to creep the timing back in when im more uses to it. Then maybe I'll have to jet it up for more power!!!
 
The reason you pull timing when on the spray is because the fuel charge is more dense and doesn’t need as much lead (time) to ignite. It’s not just as simple as pull X number of degrees for 100 shot. It takes testing and finding the value that makes the engine happy. Start low, pull 2 degrees per 50 shot, then read the plugs. Evaluate and retest. You’ll find a number where it makes the best power (mph). It will be less than your NA tune up.
 
The reason you pull timing when on the spray is because the fuel charge is more dense and doesn’t need as much lead (time) to ignite. It’s not just as simple as pull X number of degrees for 100 shot. It takes testing and finding the value that makes the engine happy. Start low, pull 2 degrees per 50 shot, then read the plugs. Evaluate and retest. You’ll find a number where it makes the best power (mph). It will be less than your NA tune up.
Thanks for the info i appreciate all the help, I followed the basic steps and recommendations from the kit and from helpful guys on here. I'll do some pulls again soon and check the plugs quickly after the hit to verify the correct timing and heat range. Unfortunately for me here on vancouver island, our historic race track was torn down for condos and a movie sound stage(last year was the final season) so I won't be able to get ET's or Mph data.... so I'm mostly going to be messing around on the street and hoping to beat my buddies on cruises. But there is tracks a bit farther away I can go race and test at to really get things dialed in later this year. Gotta hate how many tracks are dissapearing!!!!!! Good family fun gone by the wayside
 
If you can hear detonation, it was already there before being audible.

Pull the plugs, look for specks on your porcelain. Specks are usually material shedding off thing that should not be shedding (pistons).
 
If you can hear detonation, it was already there before being audible.

Pull the plugs, look for specks on your porcelain. Specks are usually material shedding off thing that should not be shedding (pistons).
I didn't really see any specs in the porcelain, maybe microscopic but hard to tell. I suppose I should hit the nitrous and check the plugs ground straps for discoloration. I just pulled them iut now and they are light colored past the curve and towards the bottom. But I drove normally on them home for 15 minutes. Any suggestion on reading the spark plugs for heat range and timing?
 
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