Safety factor of Nitrous, on the VH45DE

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elwesso
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Overview: Most of you know that I have nitrous in my Q45t, and I do have it working now... However, I have not uesd it except a tiny little bit to verify (not more than 3 seconds)

I want to know what is a safe shot to run... Right now the car has 100 shot, and I think that might be a little high... I do not want to comprise ANY miles with this.... WE all know how the VH45 is really a engineering masterpiece, but I am still skeptical after having one of these go bad... I know this one wont do the same thing...

However, I do not want to compromise ANY major miles... IE I still want to get about 200k from the engine (250k total miles).....

EDIT: I guess the bottom line question is... Is 100 shot safe for the VH45, or should I lower it a little



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pito11213
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I believe that the 100 shot is safe. I believe it was mentioned somewhere before that the Q can handle that 100 shot at stock internals.

Dude get on the highway pull up to 60MPH and see what the NOS does.

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Wes,

I've been on a self imposed sabbatical, but have been watching your NOS posts very closely.

As you may or may not remember, I have a 100 shot module on my 91 Q and have also run a 100 shot on my 91 SE-R. The SE-R now has a 50 shot prom in conjunction with 906cc (72lb) injectors on a boost program. (JWT GTi-R DET)

If I can be of any help, please, please, please, please, please post here *before* any trial/error.

IvoryJ30t
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YEAH!! spray that *****.

i cant imagine a 100 shot causing damage unless it goes lean, or you empty an entire bottle into it. 175 would be pushing it.

think of it this way- your only hitting it for 10-15 seconds at a time. a supercharger [non centrifugal] would be putting that stress on the motor everytime you get deep into the gas.

i would be more worried about the tranny. dont spray through a shift.

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Jeff Williams
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ABSOLUTELY, DO NOT SPRAY THROUGH A SHIFT, unless you are on the way to the tranny replacement shop & can coast the rest of the way.

Definitely give us some feedback on the difference of the 100 shot over stock.

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elwesso
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Remember guys, this car has a full level 10 tranny rebuild, good for 600 HP... Stage 3, with kevlar clutchs, modded valve body (quick shifts, i love it w00t!) and 2500 stall converter.....

I need to find more informaiton on the system and how it works (and please ask quesitons, so when I call rex I have a whole list)... But I would assume that this system is robust enough, that it will cut NOS right before the shift..... Not sure on that, but i dare say.....

The JWT ECU knows when Im running on race gas, or not, and compensates accordingly.. It may have been tuned for 175 shot, which would further enhance the safety..

Jason, how often do you use your nitrous... I literally CANNOT afford to lose this car due to engine failure, or from me being stupid and using NOS on the street.....

HeavyDuty
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Nitrous is like a new toy, if you ask me. Perfect power adder for someone who doesn't want/need boost all the time. Once you get it dialed in, you'll go through a tank or two a week for a couple of months, then buy a supercharger.

From your pics you have a bottle heater, remote valve, aux pump, and a fuel cell with that pump being a dedicated line from the cell to...? Is there a valve you switch to alternate between the stock tank & the cell or does the line run all the way to the front & "T" in at the filter, etc?

I'm not sure what all you have beyond that. I assume a JWT ECU with n2o module? If so, you don't have a seperate fuel solenoind & the n2o module controls the firing of the n2o solenoid & the ECU retards the timing & widens the pulse width on the injectors. How does it know you're using race fuel? Is that the 175 program? If so, it assumes you're always running the high octane stuff, it would have no way of knowing or being able to differentiate between regular 93 or the good stuff.

That's the way mine have been, but I don't know what was required for the 175 shot setup that was on here.

If that's the setup, then the module will start the flow at X rpm, then stop the flow approx 200 rpm before redline, and will only engage it when two parameters are met;

WOTX rpm

I'd be interested in hearing about your combo. You can open the ECU & read the calibration file # on the eprom to verify which program you have installed in the module.

Also, please let us know what the decal on the outside of the ECU reads.

There's a *lot* of stuff to consider here, a short list would include;

Plugs & gap (I know you're gonna hate this, no plats & I would use a one range colder plug biggrin: )

CAS (timing is everything, must be *exactly* 15 deg btdc assuming you have at least 93 octane) On my other n2o ECU, two wires on the MAF harness had to be jumped in order to force a timing change. You could NOT change base timing with the usual method with an n2o ECU. (Muy Importante) Call JWT to clarify *anyone's* advice, including mine.

TPS dialed in. .5 at rest, .45 at WOT. (Verify that, it's late)

Fuel system strength (you appear to be ok there, although the system is designed to be run with a stock pump, at least up to 100 shot)

Know that your injectors are flowing appropriately & matched. (rceng.com) This is critical.

Location & orientation of n2o nozzle in the tract (I don't like it at the TB, one or more runners gets a denser charge of fog than the others if it's too close.) I like to keep it 8"-11" away from the TB, IMHE.

Correct jetting in the n2o line. Lots of variables in your combo, or anyone's. Subtle changes elsewhere affect tuning everywhere. In other words, trust the directions but verify.

Get medical grade juice if you can, the sulphur is nasty, nasty stuff. (I have a friend who's an oral surgeon)

Get a nitrous filter installed if you don't have one.

One thing that concerned me in your post about it working.......you said you connected two wires & you heard the system purging into the intake manifold?

If that's correct & it wasn't just the sound of the line pressurizing, something's wrong.

NEVER purge into the intake if the engine is off or at idle, only when the above conditions are present.

I could go on & on, but I've probably already lost your interest.

Please try to refrain from using it until you are positive everything's perfect. You don't need a lecture on n2o horror stories, nor do you need to look for another long block to replace this one.


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DAEDALUS
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HeavyDuty wrote:Plugs & gap (I know you're gonna hate this, no plats & I would use a one range colder plug biggrin: )
What's the deal with plats on nitrous?

Quote »You could NOT change base timing with the usual method with an n2o ECU. [/quote]Any idea how the ECU knows enough to not allow you to set the timing?

Quote »TPS dialed in. .5 at rest, .45 at WOT. (Verify that, it's late) [/quote] Probably 4.5 at WOT; I'm pretty sure it's a 5v reference.


maxnix
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HeavyDuty wrote:Nitrous is like a new toy, if you ask me. Perfect power adder for someone who doesn't want/need boost all the time. Once you get it dialed in, you'll go through a tank or two a week for a couple of months, then buy a supercharger.
I think I have just heard the voice of experience! Take heed all who would suck bottled gas.

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Understand that the volume of nitrous is fixed flow. A 100 HP shot [jet] provides enough for 88 lb/ft at 6,000 rpm, 175 lb/ft at 3,000 rpms, and 210 lb/ft at 2,500 rpms.

Most get in trouble because they don't pulse the nitrous injection [by HALF]at low rpms and progressively increase duty cycle to maintain a constant torque addition with rpm increases..........AND shut the gas off just before and during the 1st shift, then progressively bring it back.

The stock JWT systems smoked the tires [any tires with only a 75 HP shot] at launch because an extra 160lb feet times gearing x friction = 1,500 added to the normal 2,500! Almost DOUBLING the power at launch

Around 2900-3100 rear gear multiplied lb/ft the rear tires will smoke and lose traction.........think Corvette here with its 3,300 rear launch lb/ft.

At launch you need 3,000 not 4,000 lb/ft

Since we prepped and installed your engine, we are always available to put another in should you not follow conservative advice.

Assume the rear tires have [4300 x 0.47 x 1.15 [weight transfer at launch] x 1.3G [tire c of F] =~~3020 lb/ft of traction launch ability].

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elwesso
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LOL Dennis.. im sure you guys wouldnt mind having another engine swap done on this 94... . Do you know if doug is sending me my service records today..?

Also, Jason, "you said you connected two wires & you heard the system purging into the intake manifold?" What happened was, I connected the 2 wires, opened the bottle, and hit WOT (car not on) and heard it purging in there... No leaks anywhere as far as I can tell, and I guess that part of the system is working...

OK, i went out to the car and snapped some photos of the system... First of all, i coudlnt get a picture of the ECU without taking it out, and that was a PITA I dont want to do again!

It says on it (exactly as written) Interestingly enough, when I pulled the ECU, there were 2 wires going inside the side of the ECU (when its mounted in stock location, its the side that faces up)

Legal in California forracing vehicles which may never ne used on the highway.

Jim Wolfe TechnologyPOP Upgrade Package94-95 Q45 TractionEQ454-NAUOT

Now for some pictures, I took these in the higest resolution possible so that you can see them easily. That said, I wil link but not post them in the thread for my comrades with dialup, as each picture is about 2mb!

http://q45.spilky.com/Q/nos/102-0271_IMG.JPG

http://q45.spilky.com/Q/nos/102-0272_IMG.JPG - This switch is the master power for everything in the next picture...

http://q45.spilky.com/Q/nos/102-0273_IMG.JPG - This has all the controls for the nitrous. The Blue toggle switch turns on the nitrous, the thing that says FUEL tank, when pushed to RH, makes it go to the race gas... WHen its on LH its on the stock fuel system...

http://q45.spilky.com/Q/nos/102-0274_IMG.JPG - This is a little confusing.. This is where the fuel filter is... The stock one is in its stock place, and then it goes up into that black thing, and there is another fuel filter, for what I would assume would be the race gas filter......

http://q45.spilky.com/Q/nos/102-0275_IMG.JPG - Just a side view of the bottle... The 2 wires that are on the carpet, are the ones that I connected.....

http://q45.spilky.com/Q/nos/102-0276_IMG.JPG - CLose up of the connectors I connected

http://q45.spilky.com/Q/nos/102-0277_IMG.JPG

http://q45.spilky.com/Q/nos/102-0278_IMG.JPG - Race gas cell and the fuel pump

http://q45.spilky.com/Q/nos/102-0279_IMG.JPG - Close up of the race gas pump and the little connector board thingy......

Thank you all for your help...

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PoorManQ45
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HeavyDuty wrote:Location & orientation of n2o nozzle in the tract (I don't like it at the TB, one or more runners gets a denser charge of fog than the others if it's too close.) I like to keep it 8"-11" away from the TB, IMHE.
Would it be ok to place the inlet for the N2O into the plenum in the rubber hose that is infront of the TB?

This may seem like a stupid question, but I don't know the answer.

While driving, can switching on the N2O cause the tranny to downshift, when the throttle is left in the same position?

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dump a 75/25 toluene xylene mix into the fuel cell.

hit the juice when the motor is running off of that brew.

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DAEDALUS wrote:
What's the deal with plats on nitrous?

Any idea how the ECU knows enough to not allow you to set the timing?

Probably 4.5 at WOT; I'm pretty sure it's a 5v reference.
According to one of the n2o manufacturers' tech line, the violent reaction of nitrous can dislodge the platinum biscuit. Beyond that, I've also heard of preignition issues, popping or backfiring. Also hearsay has it that a copper plug might fail quicker in the event of a catastrophic fuel failure. To be honest, I have asked many many people about this & had so many different answers you wouldn't believe it. I talked to NGK tech line & they confirmed in their experience, Irids are ok, plats are not.

I'd really like to hear from Tech on this, if he's interested.

The ECU timing force change was the 91 SE-R application. After installing the system along with a bunch of other stuff at the same time, I was having a hard time getting the car to accept a timing change, even after following all the required steps. The car felt lazy & was generally not impressive. Ben Pila @ JWT was the one who told me "just on the n20 module equipped ECU's is the MAF cross connect necessary to force a change." I tried it & the car immediately responded in a big way. I still don't know & haven't asked if this is the case with all JWT n2o modules for Nissans, or just a 91-95 SR20, or what makes the difference between years, etc.


HeavyDuty
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PoorManQ45 wrote:Would it be ok to place the inlet for the N2O into the plenum in the rubber hose that is infront of the TB?

This may seem like a stupid question, but I don't know the answer.

While driving, can switching on the N2O cause the tranny to downshift, when the throttle is left in the same position?
It's not a stupid question, PMQ. Not asking is where the horror stories come from. Sometimes people give wrong answers just to give an answer, when it's better to concede. Most of the guys selling "Fast & Furious" n2o kits at Autozone would fall in the "give any answer" category.

The rubber hose would be a good place, IMHO. On other cars where aftermarket intakes are available, they work a little better because you can drill, tap & seal the hole. Rubber, particularly on a MAF car, is a little tougher to seal & have it remained sealed. Then when you get a leak, the car doesn't know more air is coming in than it's metering. Make sense?

I'm sure you could come up with a good way where it's reinforced inside the intake tube & the nozzle isn't strained pulling away from the rubber at an odd angle.

Switching on a "JWT" system at part throttle will not cause a downshift. I'm not sure what Wes has, but it's intriguing so far.

If you had WOT & the required rpm to downshift without it, then you would get a downshift with it, too. (the n2o)

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PoorManQ45
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I have read that "spraying" through a shift can be very bad. But I don't actually know why.

Can you give me a little "crash" course on what happens to the transmission when you have the Nitrous "spraying" while it is shifting?


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elwesso
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When the tranny shifts, the ECU retards the timing (a lot) right befroe the shift so that it doesnt have as much enigne torque going through the tranny..

If you run NOS, even though youll still retard the engine, its still creating 100 (or whatever your shot is) extra HP on top of that.. Its kinda like doing redline clutch drops everytime you shift...

Keep the informaiton coming... Jason did you look at those pictures?

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^^ it like a neutral drop. only worse.


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damn, you beat me to it.

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elwesso
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w00t! Now we just gotta figure out what Im supposed to do.....

Im not going to even touch any buttons (if anyone knows me, this is like asking a lion to not eat red meat), much less even think about turning that valve to openup the tank, and then flipping that switch..... Until i get the consensus that it is safe to use......

The original question was... Are we 100% sure that the VH45DE will be OK with 100 shot, and no long term reliability issues... This is assuming I use it fairly conservatively (say worse case 1 time a week)

But now all this other stuff has me intrigued, please gentlemen, continue... I love learning from other people about my car!

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PoorManQ45
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elwesso wrote:
The original question was... Are we 100% sure that the VH45DE will be OK with 100 shot, and no long term reliability issues... This is assuming I use it fairly conservatively (say worse case 1 time a week)
If you want to be really safe, why not change to a lower HP shot? Between 50~75HP sounds good. This would probably be plenty.

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Hey Wes, list.

If I'm hogging this post & need to take this stuff private with Wes, I'll be glad to. I know my posts are sometimes lengthy(er) than they need to be.

I looked at your pics & have a few questions/comments.

If I viewed read your post & pics correctly, the wires you connected were for the bottle heater.(?) The little silver rectangles encased in plastic is a thermo switch for the bottle heater. http://www.holley.com/TechDocs...S.pdf

Yours is laying on the floor............

Not to be an alarmist, and though this was challenged as being fraud, it is possible for a popoff valve to malfunction alongside a faulty or non existent thermo switch that *could* result in this;http://www.saturnspeed.com/nitrousexplosion.htm

My toilet at the house simultaneously "plugged" and "ran" for about 5 hours on 4th July weekend. Same situation except mine was only a minor flood, incinvenience, a $1000 deductible and a claim I could have done without.

Disconnect the heater wires now, please. At least until you get a newer heater with an inline pressure monitoring system like this one.http://www.holley.com/HiOctn/N...6.htm

Now that that's out of the way, I'm still confused. If the system is a JWT, then when you armed the system, even with WOT it should not have purged into the system. There should be an additional decal on the ECU stating xxxNOSxxx-BR549 NOS module installed. Are either of the wires out of the ECU a faint blue color, and very thin?

Another wire should be a pre wired rocker switch. To test the system, they instruct you to engage the NOS mode, (BOTTLE OFF) and go for a short drive, then hit WOT. At WOT & X rpm, you should have a check engine light & a HUUUGE cloud of black smoke out the tailpipe.

Your switches, it seems to me should be1) JWT arming2) Remote valve3) Heater4) Fuel pump & cell 'activation'

Also, I bet a dollar the funky looking black thing under the hood is a multi tank switching system from an F150 or Chevy Silverado. It allows you to switch between tanks with your switch, have a standard full cycle fuel system (supply & return through a FPR) and keep them separate.

It could be aftermarket, of course, but that's what it is.

Nice setup, he did all the cool accessories that make it more stealthy & function better. I'm just curious why some things are doing what they're doing.

Keep me posted.


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Wes, I've seen you post several times about not compromising the longevity. Forget it. I doubt anyone will take that position. Anything you do to increase the output of something designed to run at X by running it at X + will decrease it's lifespan. Don't want to freak you out, just is what it is.

It's capable of handling a 100 shot, but the chances of a catastrophe increase exponentially with a larger shot.
PoorManQ45 wrote:If you want to be really safe, why not change to a lower HP shot? Between 50~75HP sounds good. This would probably be plenty.
They do make a 50 or 75 shot eprom, Wes, I think, fwiw. Good point, PMQ.


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HeavyDuty wrote:Wes, I've seen you post several times about not compromising the longevity. Forget it. I doubt anyone will take that position. Anything you do to increase the output of something designed to run at X by running it at X + will decrease it's lifespan. Don't want to freak you out, just is what it is.
My thoughts too. Yes it will affect longevity, but impossible to quantify by how much. Instead of lasting 300,000 miles the motor might last 250,000. Or 50,000. I doubt you're looking at anything serious anytime soon if you open it up here and there--just my feel for things. I'll bet the engine will far outlast your N2O budget! If it lasts through college, that's what, 50,000 miles? Seems likely to me that it will last at least that long with occasional laughing engine syndrome.

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Robert- Your right, honestly if the car lasts me 60k (which would put about 130k on this engine), i will be a happy guy.. Even with use of N20 I would think that it would last 150k (assuming the once a week average is abided by), correct? Always had synthetic oil (at least under Fred), and always babied..... It hasnt seen the redline (only 6500 rpm) until I got it because you have to hold it in order to get to the higher rev limiter..... Some flukey thing with JWT, I dont really care..

Jason, I unplugged my bottle heater (the 2 wires you mentioned) before I even got done... Besides the obvious, what is a bottle heater supposed to do...?

Quote »Now that that's out of the way, I'm still confused. If the system is a JWT, then when you armed the system, even with WOT it should not have purged into the system. There should be an additional decal on the ECU stating xxxNOSxxx-BR549 NOS module installed. Are either of the wires out of the ECU a faint blue color, and very thin?[/quote]II dont understand what your saying? Why wouldnt it still purge if its ON (makes sense to me)... I didnt see any other decals on there, and the wires IIRC are very very thin and fragile, and are white with green stripes. There is a red wire that I see frequently througout the car..... They could be blue, but I dont really remember... Also, on that little kick panel you have to take off to get the ECU out, there was some sort of relay and a 20a fuse... Dammit I shoulda taken more pictures.....

About the shot reduction, how would I go about doing that.. Install a new nozzle? is there like a thing, like on turbo cars, a boost controller, that I can have a max of 100 shot but then reduce it if I want.....?? I will test the system as instructed..... (arm with bottle off)

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Checking back in Sir...

I did a test run, and I got a CEL and it ran very crappy at WOT...

Just for $hits and giggles, I opened the bottle and did a couple of quick runs..... It works, and I still got a CEL.. Goddam thats fast, however, its not as fast as I thought it would be, but I didnt hold it longer for a second at a time... And I was in second gear.....

This is gonna be hard not to use!

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The bottle heater keeps the bottle from getting too cold under use. Most NOS kits come with several jets of varying sizes so you can choose your shot. I'm sure you can buy just the jets if you want to change it.

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On the purge issue, I don't think it should engage (open) the solenoid if the engine is off. If yours is the JWT setup & not a modified JWT, it doesn't fire the solenoid until it reads WOT *and* X rpm. If the car was off, no rpm, that's why I'm confused, too.

Off the shelf NOS systems use a microswitch that fires the solenoid like you're saying you did. This system isn't like those though. I think what you heard was the remote bottle valve opening & filling the line, at least that's what I hope you heard.

The wires, relay & fuse behind the kickpanel is what the ECU NOS module uses to fire the solenoid. The nitrous flow is controlled by the module, not a WOT microswitch.

Particularly since you live in a cold climate, in order to get the greatest pressure differentiation between the bottle & the atmosphere, a heater thermostatically maintains the bottle temp at 85 degrees. That, in turn, maintains a good pressure inside the tank of ~950 psi. Warm, high pressure good, cold low pressure bad.

Since your system is so sophisticated, (it's really a base system & a progressive, rpm/WOT based engagement & disengagement, nitrous/fuel/timing controller added on to your ECU) in order to reduce the shot, you need a new n2o eprom installed in the NOS module inside the ECU, along with the correct jet in the nitrous feed line.

If you were to just reduce the jet in the line, you'd run rich because the system wouldn't know you changed it to a smaller jet. (more fuel less nitrous)

Even worse, if you were to change the jet to a larger one & didn't have the appropriate eprom to adjust for more fuel & possibly even further reduced timing, you run lean. (more nitrous less fuel = boom)

There's no cockpit adjustable controller that I know of, except for stand-alone engine management like the AEM Plug & Pray.

Edit: P.S.Pull your bottle out & weigh it. Empty weight is 14lbs x ounces. A full bottle should weigh 24lbs, x ounces. Good luck getting someone to give you a full bottle though. When you run low on nitrous, the car won't perform anywhere near what it should, it'll be fat (too much fuel) & lazy(reduced ignition timing), like me.

I actually told a customer one time he was rich & retarded.....that is...rich in fuel & retarded timing.

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First buy and READ the various books on Nitrous, memorize them so every formula and comma is imbedded in your brain. So you can do the density math without a calculator.

A 75 HP jet yields ~~66 lb/ft [60-70] at 6,000 rpm. At 3,000 rpm this doubles to 132 lb/ft ;........ at 2250 it's =165 lb/ft because the nitrous volume is constant [assumming the pressure is constant].

Assume that an extra 165 x 0.8 = 132 lb/ft gets to the rear tires multiplied by 9.85 = 1300 extra pound feet over and above what ever the engine use to create 200 x 9.85= ~~2000 lb/ft + 1300= 3300 lb/ft at nitrous launch.

The BEST tires can only support 1.3 G launch, with rear weight shift the tires might see 1100 pounds of weight each so 2200 x 1.3= 2860 lb/ft......lesser tires might only allow 2200 x 1.1 G= 2,420 lb/ft. All seasons might be 2200 x 0.9=1980 lb/ft

OBVIOUSLY ZERO to 400-500-800 lb/ft is what is needed to not waste time spinning the tires not an extra 1300 lb/ft so a pulse control system for Nitrous and fuel is needed something between 30% and 60% [100% with bad hard tires] reduction [from a 75 HP JET] depending on rear tires at 2250 rpms launch.

As the rpm rises so does engine torque [to 4,000 rpm] but the nitrous induced torque falls [based on air flow] so you need to create a graph showing the net TORQUE at each rpm increment!

So with maybe 300 x 0.787 x 9.85= ~~2325 lb/ft the lesser tires might spin/slip [or very close too it] at 4,000 rpm without NITROUS!!!!!!!!!!!!!

{{MY PROBLEM with H4 400 tread wear index tires and JWT ecu is rear tire spinning/slipping from 30-40 mph}} without Nitrous when trunk empty and gasoline low..........140-200 pounds less traction in rear.

Now 4.083 rear gears but a 94 tranny net nets a 9% torque increase to rear wheels less any additional friction from the rear diff based on speed.The diff is every inefficient at low speeds say 91-92% at launch rising to 97% at 55 mph......has to do with fluid shear and diff fluid temperature.

The other problem is you will exceed the power rating for the VISCOUS Limited slip which will overheat and progressive fail as the plates warp.Not instantly on a new one but over time.......so what ever you do don't let the rear tires spin for long or repeatedly. No smokey burnouts allowed or you will be replacing lots of diffs.

Where Nitrous is best is in second gear as the multipled torque is reduced by 45% and the gear multiplier is 5.55 [oem 90-93] not 9.85 as in 1st gear.Or 6.00 with 94 tranny and 4.083 diff gear.= ~~ 1900 lb/ft rear with 75 HP JET at 4,000 rpm [807 rpm/10=50 mph].

IF you only use Nitrous in 2nd gear a 100 HP JET with progressive pulsing would be better as you are leaving a little on the table with a 75 HP JET to get to 2100 lb/ft at 50 mph [with 94 tranny and4.083 diff] to just almost spin the tires.

Most Nitrous systems are not tuned this finely so they waste time spinning tires or worse waste power overstressing the engine and drive line.

Notice that newer 5-6 speed AT by BMW/LS430 use a 1st gear multiplier of say 13 vs our 9.85 or 11.37 [with 4.083] or 10.8 [with 94 AT and 4.083].


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PoorManQ45
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Joined: Fri Jul 02, 2004 5:13 pm

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Q45tech wrote:The other problem is you will exceed the power rating for the VISCOUS Limited slip which will overheat and progressive fail as the plates warp.Not instantly on a new one but over time.......so what ever you do don't let the rear tires spin for long or repeatedly. No smokey burnouts allowed or you will be replacing lots of diffs.
Does anybody make a Locking Type LSD? Meaning it functions like a normal LSD while turning, but when going in a straight line and applied torque reachs a certain amount, the LSD "locks-up" causing the wheels to spin at the same speed. Kind of like posi-traction.

If noone makes one specifically for the Q45, does anyone make one for the 300zx or another car that will work with the Q45?

I've been reading about this a little bit. It would seem that for best track times, you would use a dual stage nitrous setup.

First stage = 25~50hpSecond stage = 75hp~150hp

The first stage ingages shortly after launch, here are variables:Gear must = 1stSpeed = 10mph minimum (To prevent tire slippage)Throttle Position = 75% or greaterMaximum RPM = 100 RPMs before Redline (as not to spray through shift)

The second stage could be the same as normal, but not ingaging while 1st stage is ingaged.

What effect would this have on the 1/4mile time?

How complicated would this be to impliment?A new ECU N2O module would be needed. Another line run from the bottle to the intake. 25~50hp jets installed on the new line. What else would be required?


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