A Little Help With NOS

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plum70crazy

plum70crazy

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This is JUST a curiosity. I have been thinking about toying around a bit. I have a 318 in my duster. The motor runs well and drives nicely down the road, but I have a question.

What would the impact of a small 50-75 shot of Nitrous be on the motor over all? The guy before me said the motor has something like 8:1 compression. 3.55 gears in the rear end - just rebuilt. I just wonder what the impact would be over the long term.

Any thoughts? I have no experience with Nitrous
 
NOS can be fun. It can also be a b&tch! I say the best way to approach it, being a new user, would be to buy a new kit from a well know name brand such as NOS. The new kits from NOS come with a jet chart with recommended jetting. These jets are rich and very safe tune ups. Once you have your kit and your ready to install it, I recommend that you use a dedicated fuel source for the fuel solenoid. The way I did it, I put a fitting in the stock tank and ran a 3/8 fuel line up to a dedicated regulator then to the fuel solenoid only. I used the stock pump and line to feed the carb. Once the kit and fuel line were established its time to play. The tune up is the next most important part. First I retard it 2 degrees of timing for every 50hp of nitrous. Then I run a spark plug that is two steps colder than I would normally run. I also set the fuel pressure to exactly what the jet chart wants, and the way I do it is I have a spare AN fitting and a hose with a similar size jet installed in the end. I then take off the fuel line to the solenoid and install this spare line and fitting and turn the pump on. Then I set it to the PSI indicated on the jet chart while the fuel is actually flowing. As a driver you need to be very familiar with your car and how it runs. One thing some people do is that they fail to recognize when it is not pulling like normal. This usually means that the fuel solenoid is stuck shut. Especially on a small kit. This will kill a motor. If you motor has cast pistons you need to stay very away from detonation, it will shatter a cast piston. Also if the car gets out of shape or spins wildly then let out and stay out of it. NOS is great and can be a lot of fun. I have used up to 300 shot on a cast piston motor, it made it 50 passes and then the solenoid stuck and I let out as quick as I could, it didn't even backfire but it broke 2 pistons. At 150 it lived for years with no problem, just when I got greedy and upped the jet size is when I had the problems. I would think a 100 shot on any motor will live as long as its healthy and used properly.
 
Thank you for the reply,
I had considered the fact that the kit should be purchased as a whole unit. I was also aware of the fact that balancing the entire package was the key. Now the question is, would a 50 shot even really be worth it? In other words, is starting small and then jetting it for the 75 shot the scale that I should consider? Or, should 75 be safe and build from there? I want to notice the power, but this is something that, if pursued, I will work with very slowly.
 
Do you think I can run a 100 shot with my setup? I have a 318 with about 10/1 compression with cast pistons, mp 528 solid cam, and ported iron heads with 1.88 and 1.60 valves. It still has the stock mec fuel pump.

The engine is running great, but I'm afraid of breaking something running nos.
 
go to Wilson performance manifolds they make the best set up iv seen to date and 100 shot of spray no problem don't think i would go over 175 shot but 150 i would run on a stock engine just remember you have to change your timming when running spray.
 
FACTORY CHRYSLER cast pistons can take about 100-150 shot with no trouble as long as you don't try to lean it out like a blowtorch lookin for every last bit of E.T. I would not run a "dry" shot. No way, no how. If you're gonna run it, run a wet shot that injects fuel too and keep it a little on the fat side. This will keep it from burning your pistons. Of course anything is possible if you abuse the hell out of it. Just avoid the temptation to lean it out to speed it up more and you'll probably be fine.
 
StrokerScamp said:
FACTORY CHRYSLER cast pistons can take about 100-150 shot with no trouble as long as you don't try to lean it out like a blowtorch lookin for every last bit of E.T. I would not run a "dry" shot. No way, no how. If you're gonna run it, run a wet shot that injects fuel too and keep it a little on the fat side. This will keep it from burning your pistons. Of course anything is possible if you abuse the hell out of it. Just avoid the temptation to lean it out to speed it up more and you'll probably be fine.
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Thanks,
From what I originally understood, the "fogger plate" that sits where the Pie Pan rests mixes the fuel and NOS as it progresses through the venturi. I may be way off, but from what I read in a earlier post, a new fuel pump, lines and solenoid would run in line with the original fuel line (I am thinking that this may be the "wet shot" you are talking about). As I said earlier, I am an absolute rookie to this and was hunting for info. I am going to continue to gather info. I never jump into a new project, and this was just the info. gathering stage, but I am way below the curve apparently. Might be time to hunt down someone local as a resource.

As far as the 50 HP being noticed, I recognized that, but didn't know whether there would be enough difference between the 50 and the 75 shot. I also wondered about the durability as it may impact the pistons.

Again thanks for the info.
 
You will not be happy for long with just a 50-75 shot for long, just start off with 100 pills, I like the Sniper kit from NOS, its good to 150 & thats all you will need on a stock short block, If tuned right it'll knock of a solid 1.5 sceonds & up to 13-15 MPH, The main things you will need to keep things safe. You can get away with just the T off on a 125 shot, But, you need a good pump like the Carter street/strip pump, you will need to run a reg. with this pump, It can put out a solid 9-10 lbs. pressure, I know some will say run a seperate fuel line for the Nitrous, its really not needed on a 125, especially the NOS kit, there on the richer end for safety, You really need to set the pressure flowing through the plate, not just an open line because it will be higher once hooked up going through the thin bar & spray holes. You really don't need to get very technical on a 125 shot, It will be fine, These are the upgrades i would do anyways as a given, Now once you start useing the 150 pills thats when its times to up-grade to a cell or sump the tank & run a seperate line & reg.

1. Get a good ignition system with an easy adjustable dist. so you can pull timing & curve it in.
2. Get a better fuel pump.
3. Run plugs 1 step colder & tighten the gap setting to .030", I step colder from stock is all thats needed for a 125, I really like NGKs V gap, they are easy to read.
4. On a 125 pull about 4-5* timing, then adj. up-down 1 deg. at a time untill you get the best MPH
5. Being new to this i wouldn't start messing around with the set chart pills, just stay with the chart.
6. Get a cowl mounted gauge so you can monitor pressure at all times, You can run a shut off for the Nitrous if the pressure drops below a set pressure, but i've heard they are not always accurate & tend to acted up.
7. If you can buy a Y fitting that would be better then a T, Just run the main line from the pump up to the Y & branch off to the carb/Noid, I would set the pressure at no more then 6 lbs. for both'
8. You can run an in line pressure gauge right before the carb, set the pressure, then run it WOT on motor & see how it does, if it stay fairly steady at 6 lbs., you'll be fine opening up the nitrous, the gauge may blurp abruptly but regain control quick (thats fine), it really won't drop that much on a 125.
9. Put you a brass fitting at the inlet of the carb main line so you can install the under hood gauge & run the line for the main cowl gauge.
10. You should be fine on Pump Premium fuel.

There are a few other things i thought about but i'm drawing a blank, If i think of them i'll add it in.

I ran the Sniper on my last Dart i had, I used the 125 pills & set the timing at 28* total, ran 1 step colder plugs, Used the T, had an elec. pump thats wasn't that steady (didn't know it at the time because i didn't have a cowl mounted gauge yet hmmmm), On motor car ran 8.3s @ 82- 83 that night on 1.90 60 fts.:angry7:, the weather was pucky, it normally ran consistant 1.80 60fts & 8.0s @ 85-86, On the 125 pills & pressure drifting from 5-6.5 lbs. this is what it ran with no i'll affects.

1.75 60ft. from 1.90, 7.48 @ 95 from 8.3s @ 84 & i had to abruptly lift do to drifting in the other lane, I went back 3 weeks later looking for that 7.2 pass, It was on its game that night, 8.09/8.13 @ 84-85 on 1.81s, I couldn't get any traction at all off the line :disgust:, but the car still gained 11-12 MPH on every pass, I ran the 1/8 most of the time.

BTW, this was on a 95 junkyard 360 magnum block with cast pistons, bolt-ons & small re-ground cam, kepped the shifts at 5100, 3.73 gears, 11" 2800 stall, My goal was 7.0s @ 99 on 175 pills.
 
I would not get that "pie pan" thing. That's just gimmicky bullshit. Stick with an under carb plate and you'll be fine.
 
I started with Nos cheater system. It has big solenoids that are less prone to dirt and problems. A 50 shot is pretty small but will be noticeable. The problem with nitrous, well any power adder as a fact, is that you can easily up the HP till you meet whatever unrealistic goal your shooting for. Thats where most guys get into trouble. Joedust451 has some great info. Like I said before I would buy the kit new from NOS and then their tech knowledge is all yours. They were local to me when they were family owned. When I first started they even hooked me up with one of their sponsored racers for tech advice. I went to the track with him a few times and watched and asked questions. Then when it was my turn I went to the track when I knew he would be there. He was a valuable resource and it worked well for me. With the 100 shot my 12.0 car became a 11.0 car and picked up 10 mph. The 150 shot put me really deep into the 10's and picked up 5 more mph.
 
Do the kits have everything you need? I was looking at the Sniper kits earlier, and it looks complete. Is there a way to run a delay so it comes on at say 2 or 3 seconds after you hit WOT?
 
Thanks, This is great info. I understand that the power adders will work until the weakest link in the system takes a dump. My original curiosity stemmed from the concept that it would be fun to add a little nudge to the Duster without being a time bomb that I would have to worry about all the time. I will check out the NOS cheater and the Sniper systems and see where it goes.
 
64physhy said:
Do the kits have everything you need? I was looking at the Sniper kits earlier, and it looks complete. Is there a way to run a delay so it comes on at say 2 or 3 seconds after you hit WOT?
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You would need a nitrous controller to achieve that. One cheap and easy way to soften the hit is to move the nitrous solenoid further away from the plate by making the line longer. It will delay the hit and make it softer to help with the hook.
 
turbodart68 said:
You would need a nitrous controller to achieve that. One cheap and easy way to soften the hit is to move the nitrous solenoid further away from the plate by making the line longer. It will delay the hit and make it softer to help with the hook.
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That's a good idea. Thanks!
 
64physhy said:
Do the kits have everything you need? I was looking at the Sniper kits earlier, and it looks complete. Is there a way to run a delay so it comes on at say 2 or 3 seconds after you hit WOT?
Click to expand...

Your set up is ready for a 200 shot! Transbrake 5000RPM out of the hole and have the Juice hit as soon as you let the brake go! Yeah!!:D

What Ignition Box are you using?
 
I'm running an MSD E-Curve, no box. Once i ever get the cage and seats, then I'll juice it, but probably start with 100 shot.
 
turbodart68 said:
One cheap and easy way to soften the hit is to move the nitrous solenoid further away from the plate by making the line longer. It will delay the hit and make it softer to help with the hook.
Click to expand...

I've heard this works, how well don't know, but remember the farther away the noid is from the plate your chances of air between the 2 increases, then running a purge becomes a must. My advice to the OP is run an ET street or Hoosier QTP tire, they WILL hook at the track right out of the gate, Getting the 60ft. down is key, thats when the ETs will drop, If you start delaying too much your loosing ET, get the car to hook, you would be surprized how much faster the ET drops on the bottle vs NA, so a 20-25ft. delay could be .2 easy on the bottle. If you go with DRs, I strongly advise running the Hoosier DR not the MT, the hoosier is much softer & they hook hard, I played hell getting my dart to hook on the MTs on street night, Even delaying the hit 20-30ft. out, it still blew them off every pass.
 
JoeDust451 said:
I've heard this works, how well don't know, but remember the farther away the noid is from the plate your chances of air between the 2 increases, then running a purge becomes a must. My advice to the OP is run an ET street or Hoosier QTP tire, they WILL hook at the track right out of the gate, Getting the 60ft. down is key, thats when the ETs will drop, If you start delaying too much your loosing ET, get the car to hook, you would be surprized how much faster the ET drops on the bottle vs NA, so a 20-25ft. delay could be .2 easy on the bottle. If you go with DRs, I strongly advise running the Hoosier DR not the MT, the hoosier is much softer & they hook hard, I played hell getting my dart to hook on the MTs on street night, Even delaying the hit 20-30ft. out, it still blew them off every pass.
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I have done it myself and it works like magic. A purge has nothing to do with the amount of air in between the solenoid and the plate since its on the other side of the solenoid. Actually you want air in the line between the solenoid and plate, thats what softens the blow. Of course you leave the fuel solenoid in the stock location and it actually creates a rich condition right before it hits and that softens the blow too. Ever watch the early Fastest Street Car shootouts? That huge plume of black smoke is from this very tactic employed, thats where I learned how to do it anyways. Of course thats with a 500-600 hit of the hooch, so its a lot of fuel! A nitrous car is balancing act as with other power adders as well. Get the hit right and the tire will be ahead of the traction curve and it will go faster, if you hit it too hard then you are behind all the way down and a lot of cars meet the wall from black tracking.
 
turbodart68 said:
I have done it myself and it works like magic. A purge has nothing to do with the amount of air in between the solenoid and the plate since its on the other side of the solenoid. Actually you want air in the line between the solenoid and plate, thats what softens the blow. Of course you leave the fuel solenoid in the stock location and it actually creates a rich condition right before it hits and that softens the blow too. Ever watch the early Fastest Street Car shootouts? That huge plume of black smoke is from this very tactic employed, thats where I learned how to do it anyways. Of course thats with a 500-600 hit of the hooch, so its a lot of fuel! A nitrous car is balancing act as with other power adders as well. Get the hit right and the tire will be ahead of the traction curve and it will go faster, if you hit it too hard then you are behind all the way down and a lot of cars meet the wall from black tracking.
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Not trying to be rude but your incurrect on how purging works, It has everything to do with clearing the air, thats what its designed for, Your right if you have air in the lines it'll soften the hit, but that happens when there is no purging, Ask any guy that knows nitrous & you can be garuanteed he will tell you the same thing, Monte Smith comes to mind, give him a ring.
 
JoeDust451 said:
Not trying to be rude but your incurrect on how purging works, It has everything to do with clearing the air, thats what its designed for, Your right if you have air in the lines it'll soften the hit, but that happens when there is no purging, Ask any guy that knows nitrous & you can be garuanteed he will tell you the same thing, Monte Smith comes to mind, give him a ring.
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A purge is only going to clear the line from the bottle to the NOS Selonoid, everything after that it does not clear. So from the NOS Solenoid to the Jet is where the conflict here is. However Turbodart68 is correct on this one. Shorter Line after the Solenoid less air in the line, longer line after the Solenoid more air in the line. If your NOS Jet was attached directly to the NOS Solenoid, then you would be correct, there would be very little if any air in the line because there is no line. There is no way to hook up to your plate that way though.

Please correct me if my thinking is wrong.
 
Mad Dart said:
A purge is only going to clear the line from the bottle to the NOS Selonoid, everything after that it does not clear. So from the NOS Solenoid to the Jet is where the conflict here is. However Turbodart68 is correct on this one. Shorter Line after the Solenoid less air in the line, longer line after the Solenoid more air in the line. If your NOS Jet was attached directly to the NOS Solenoid, then you would be correct, there would be very little if any air in the line because there is no line. There is no way to hook up to your plate that way though.

Please correct me if my thinking is wrong.
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Thats what i'm talking about, Who in there right mind would leave 8-10" of line between the noid & jet with a purge, kind of defeats the purpose, But i jumped the gun on his post, he is currect, i read into it wrong, I will say that most all the big racers feed right of the plate, They don't have any delays in the nitrous, thats what timing controllers/stages of the hit & RPM controllers are there for, all these help to control the hit, The biggest factor is the suspention & tire, the better they work, the more you can leave on.
 
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