cyberz350

iTrader: (3)

This is long so if you're lazy:

Went on dyno, sprayed, intake blew up, bought Nismo intake.


If you're curious:

So I take the Z to the dyno again today to find make sure the nitrous system was running o.k. because of the low numbers I got last time. I sprayed it at about 1000 psi with 100 shot jets and only got around 280 something. Which is ridiculous because I got 321 on the same jets. I suspect an empty bottle so I purge and all that comes out is air. So I go get the bottle filled. Come back, strap it on, reheat the bottle to around 1000 PSI. We get on the dyno, in 5th gear, floor it, activate the spray, 2 seconds later...BOOOOOOOOM!!!! I swear to god I thought I was being punked or something. I see shiet fly all over the garage. At this point I'm thinking ****, my engine is GONE, I'm expecting to see a big azz puddle of oil and coolant on the floor, a hole in the block the size of my head, and a couple rods and pistons lying around. Luckily I see none of these things, however, I see remains of what used to be my intake, that shiet exploded.

At this point, I am holding back tears, I swear I was bout to go to a corner and start rocking back and forth in fetal position. So I take it off and make an inspection of the engine, nothing really crazy, just filter element everywhere. So I call the dealer to see how much for a replacement (hoping to god my MAF wasn't ****ing blown) $430 something , yea right, check performance nissans website, they got a nismo intake for 269. I ask the dealer if they have a nismo in and they say they do but their charging $439. Hahahaha, Riiiiiiiight!!!

Me: Can you guys match a price?
Dealer: From where?
Me: Performance Nissan in Duarte.
Dealer: How much?
Me: 279?
Dealer: *silence* I doubt they will go that low
Me: Can I talk to someone else who will go that low?

So I got the intake for 300 after taxes. I put install it, try to start it, starts up but doesn't stay on, I'M ****ED! I take out the MAF and try to clean it a little, come to find out I had the MAF installed backwards also (not sure if that was the problem or the dirty MAF). Put everything back in and it starts up and purs like a kitten.

What could've caused it? Not sure, could've been a couple things. What I'm pretty sure happened though is the nitrous/fuel mix that was in the intake system was ignited. I'm open to suggestions but as of now the nitrous system is out of commission and I'm calling NX first thing in the morning. Enjoy the pics

cyberz350

iTrader: (3)

remains pt.2

cyberz350

iTrader: (3)

Replacement.

AmyCroft

iTrader: (3)

As I recall the MAF Sensor operates by the amount of air
flowing over a "Heated Wire" the change in temperature / resitance of the wire is then converted to a 0 to 5.2 Volt signal..

Of course it probably was a backfire - as the Car hit the RPM limiter..

Cheers Amy -

( The car threw up ! )

How were the Dyno Results?

Z BOY

iTrader: (41)

Yeah, lets see what the dyno showed. Did you hit the rev limiter?
Glad things turned out ok. That was too much drama for one day.
I bet you were alternately cursing yourself, nx, and whoever else you could think of for a while. Oliver, can you laugh about it yet?
Now that your z is ok, it was a rather hilarious story

cyberz350

iTrader: (3)

Well...I'm ok about it now that is running right, but I won't be able to laugh at it till I get a compression check to make sure everything is good.

As for hitting the rev limiter, no dice, it happened around 4500 rpm. And for some reason, when I activated the nitrous, it went immediately rich, right off the map, under 10, I'm not sure if this could cause a backfire but it probably did. I don't understand it because these are the same jets that ran the 321 HP and 387 TQ numbers a month ago. I was running rich then but nothing like this happened.

There's still a lot of things on the top of my head that I have to check that might be the problem:

1. Fuel solenoid
2. Nitrous solenoid
3. Spark Plugs
4. Propane used to fill up bottle instead of Nitrous

cyberz350

iTrader: (3)

So I did some googling,

What happened was a nitrous backfire, duh, but I found out that it can be caused by an overly rich condition. Now the question is, why was it running rich? Reading up on that stuff has kind of freaked me out, I think I'm gonna google how to do a compression check and do it asap. I'm leaning towards failed or failing nitrous solenoid at the moment.

Z BOY

iTrader: (41)

Well, your nismo intake looks cool.

raylomas26

When I was 17 I had a `66 Chrysler 300 with a 383 and a fixed 125hp plate system. I broke the cardinal rule of "don't tamper with the kit" and decided to open up the spraybar ports with a tiny jewlers drillbit. The holes were approximately twice the size when I was done. I took it out to a stretch of highway that was ournormal drag racing spot and hit the juice. WOW it was a massive burst of power, quite a bit more than the 125hp plate was when it was untouched, like a big fat guy sitting on me. That lasted all of 3 seconds which was long enough to get something in the combustion chamber of one or more cylinders hot enough to ignite an incoming charge (spark plugs most likely) and BOOM. It was enough to blow apart a screen mesh Edelbrock air cleaner, twisted it up so I couldn't use it anymore and toasted the element. Lucky the engine was ok and I drove home. Learned my lesson about getting ham handed with a nitrous kit.

(An excessively rich mixture can do that because the nitrous burns all of the gas up making more heat than a normal shot would)

cyberz350

iTrader: (3)

Scary stuff man, see I'm pretty sure its not the plugs though because I did a baseline before I went and filled up the nitrous bottle. And I got 235hp and the A/F seemed normal.

MySunset350Z

iTrader: (23)

i dont think it was a good idea to use the stock intake setup with nitrous. also, another thing you need to be sure to do is mount the fogger as close as possible to the throttle body. this minimizes how much the nitrous and fuel heat up before reaching the combustion chamber.

you should also invest in a wideband a/f guage. you would of noticed it bounce off the rich end if that was cause by a rich condition. in that case it would of been either the the jets sizes or a dying nitrous seleniod which is covered under warranty by NX.

good luck.

Mar3oob

Just wondering if the NOS is activated by a micro switch or by tapping into the TPS.

Reason for this is that I have seen/experianced this sort of thing before and it usually is around the shift point when we let of the throttle and the throttle plate closes while the NOS is still flowing.

No if you are using a micro switch for activation and given that the 350z is drive by wire (electronic throttle control) I am just wondering if the ecu decided to close the throttle for some reason. Maybe went into limp mode? or some other fail safe?

Anyways I think if that is the reason then we should start thinking about micro switch activation vs TPS activation. I would rather use TPS

MySunset350Z

iTrader: (23)

NX has the micro switch setup. its actally a wide open throttle switch. its basically a stand alone system so no programming is required.

mar3oob....why are you scared?

Mar3oob

Hey dont get me wrong I am a big believer in NOS. I am just not comfortable with the ECU deciding to close the throttle plate as it pleases!!! I am also not against micro switch activation, as long as its activated by the throttle plate itself and not the throttle pedal.

MySunset350Z

iTrader: (23)

i see your point, but we dont have a throttle plate on the z since its drive by wire. we have to install it to where the pedal activates it.

when i said why are you "scared" i was referring to your name. isnt that what mar3oob means?

Mar3oob

ROFLMAO!!!!!! I didnt think for a second you were referring to the name!!!!! I guess I just like the name

Well your right the Z is drive by wire, but it doesnt mean that it doesnt have a throttle shaft. If you really wanted to, you could extend the throttle shaft and install your micro switch there.

Bahraini350Z

what a silly name

MySunset350Z

iTrader: (23)

a lot of z's in bahrain eh?

cyberz350

iTrader: (3)

Ok, here's an update:

I did a compression check to make sure everything was good in the hood inside my engine. And I got consistent 190s all around so I'm happy about that.

While I was doing the compression check I checked out my plugs they seemed to be fine, no fouled plugs.

So here's what I've checked so far:

-I've checked and made sure both nitrous and fuel solenoids open and close as well as checking to make they aren't leaking.

-I've checked the spark plugs and they aren't fouled (1 step colder NGK coppers)

-I double checked the jet settings with NX and they say it checks through (52 N 31F)

-When the intake blew, the bottle pressure was at around 1000, I hit the switch at 3500rpms, it blew at around 4 to 5K way before redline.

Previously I dyno'd with the same jet settings(52N, 31F) and got 321hp and 387tq.





I'm pretty much out of things to test. The only other thing I can thing of is that I recently installed a pressure regulated heater and a digital pressure gauge. When I installed the adaptor for those I used some teflon tape because the adaptors were leaking. I suppose it could be possible that part of the teflon tape could've came loose and blocked the nitrous line thus causing a overly rich condition and causing the nitrous backfire.

If you guys have any other suggestions please let me know. I don't want to spray until I'm sure of the cause of the explosion.

fiveohpatrol

I was referred to this thread by JimRHIT

You should NEVER use teflon tape on any fittings in a nitrous system, period. Use teflon sealing paste only, and let it dry.

I'd recommend removing all of your fittings and lines and checking them all. Also, hopefully you were supplied a nitrous inline "filter" with the kit, if so, take that off and check it for clogging. If you don't have one, get one and install it on the bottle side of the N20 solenoid.

One more thing, you might want to check for any loose wiring that could have caused your nitrous noid to temporarily stop working. Just another idea.

And people, please stop calling it NOS!