DTN

Since someone changed my title I decided it was a good time to share this and explain the title.

I've had a few nitrous backfires and they are expensive. They usually happen from shooting nitrous at too high or too low RPM. Each and every time my air filter blew up to a perfect circle instead of a cone. Each time my MAF was destroyed. Each time all 5s silicone couplers in my intake was separated from the next section of pipe.

My system is a TPS activated system. I don't have a window switch. It's very hard to pay attention to your RPM while experiencing the invigoration of nitrous. Sometimes you can forget to switch the nitrous off and give it gas in too low of an RPM. Word to those who are considering nitrous, get a window switch. Nitrous backfires suck and you need to change your MAF and Air filter afterwards.

Here's the stories behind my backfires.

1. I tried to use nitrous from a dead stop. It didn't work. I ended up buying a new MAF and Air filter.

2. I was road testing my nitrous and forgot to turn it off. When I tried to floor it, the nitrous kicked on and exploded my intake. New MAF and air filter was required

3. I was at a car show. I was explaining to some guy how nitrous worked with the enging off and fired a quick shot into my intake while explaining, then flipped the nitrous switch off. My buddy told me that my battery voltage was low after he glanced at the voltage indicator in my trunk, so I turned on my car and just for fun I reved the engine. There was a dead silence as if to prepare for the explosion and then BOOM... The the entire show stopped, looked at me, and I was sitting there shocked in a cloud of smoke like WTF? I put it all back together, won a random set of C-Clamps/ Clip clamps at that show, then drove my car home without a MAF. I had to replace the MAF and air filter.

Other cars nitrous backfire vids...

on a dyno, most ammusing:
http://youtube.com/watch?v=wX1-LgDA1Go

on a track
http://youtube.com/watch?v=9bRbd3-Myg0


So yeah, nitrous isn't as damaging with our cars as it can be to others. It still kinda sucks, and a window switch will prevent this. I am trying to find one for a decent price. Hope you were entertained by this post.

radu_rd2

You should mention this in the nitrous DIY, people might not read this thread later.
You should also change your name to Mr. DrivingTib "I blew up my freakin intake" Naked smile.gif

MAXXTIB

When I was spraying the go juice in the tib I would always spray right off the line as soon as the throttle position hit 90% it would come on full blast, that was with an 80hp shot, I had one slight backfire when it was first installed and I talked to a local tuner shop about it and he told me to drill the nozzle into the intake manifold right after the throttle body, this way when you close the throttle no nitrous and fuel can get trapped in the intake pipe causing it to backfire and blow everything apart, so after doing that it never happand again. the backfire problem is more of a problem with single nozzle systems rather than the direct port. So if your running a single nozzle kit I would highly recommend you move the jet to the manifold right after the throttle body and I'll bet your problem will be gone. Alot of people don't realize that when you go to wide open throttle there is a slight pause in the airflow, it slows down when going from vaccum to none and at that time the small amount of nitrous and fuel can puddle in the intake pipe or anywhere the nozzle is located and on some occasions that exessive amount can explode, it seems to me that your nitrous may be coming on before you hit full throttle causing even more to puddle in your intake and BOOM, moving the nozzle should also help out with that as well, that and make sure it is spraying in the right direction, seen a few people do that.

demon_fox

wow owned.gif

DTN

You are not just wrong, you're trying to get people to blow up 1 or 2 cylinders of their car.

the manufacturer specifies to place the nozzle 6" from the TB on the non-vacuum side. This is because inside the manifold there is no guessing where the air will go.

If you put the nozzle inside the manifold the nitrous will generally go to cylinder 1, 2, 3, or 4. The nitrous and fuel come out of the nozzle pressurized and require distance to mix properly with the air. This will increase temperatures and risk damage to the engine. there is no good place to put it inside the intake manifold because there is not enough distance for it to properly mix with the air.

Don't put a nitrous nozel on the manifold unless it's to each runner individually. Look at professional installs and examples on company websites, not the guy at your local tuner shop.

A window switch is the proper answer. A hot valve comming up at low RPM with some still burning fuel in the cylindar will ignite the nitrous which decreases the gasoline's flashpoint. WOT at low RPM leaves unburned fuel. A window switch will keep the nitrous from entering the system until the system is ready.

MAXXTIB

I was just lucky I guess, but considering my car has 80,000 miles on it and Ive been pushing 10lbs of boost along with the 80hp shot all into a stock motor with nothing but a head spacer I would say it worked just fine for me plus all the other mods like airram intake and BBTB car still runs great and burns no oil at all, and I have beat the hell out of ever since the day I picked it up from the dealer, only problem I ever had was when I blew the differential out on it. I was well aware of the six inch rule for the nozzle placement but as you can see it didn't work to well in your case or mine in the beginning, but my car would backfire when I let off the gas not when I stepped on it, well anyway best of luck to ya.

DTN

^^You don't have fuel management or timing retard? You should retard your timing for anything above 50 hp. You have lower compression cylinders which prevents predet and higher temps.

MAXXTIB

Of course I have fuel management, I didn't mention it due to the fact that it is obvious that I must, I ran a standalone(prs8) for a while but do to emmission reasons I went back to a stock ecu along with an emanage plus MSD ignition and I also run a methonal injection as well, I didn't have a problem when I ran the prs8, but when I went to the stock ecu I did for some reason, I should of also mentioned that I did'nt tap the nozzle directly into the intake but I made a spacer from 1/2" steel and placed it between the intake and bbtb and tapped the nozzle into that. as far as ignition retard I never had to do it, I always run 93 octane fuel along with the head spacer and colder plugs plus the methonal injection on the hotter days, like I said everything worked well once I moved the nozzle to the other side of the throttle body like Scott Shafiroff said I should, the guy has been building Ntrous motors since the 70's, It might be differant since I was running a turbo. Just so you know I'm not trying to be a smart ass about it, I'm just stating what worked for me and you are 100% right about where the manufacturer says to place the nozzle, it just caused me problems for some reason.