Nitrous backfires

T

Todd W

Comp Diesel Sponsor
Joined
Nov 18, 2006
Messages
784
How do they occur? what conditions must be present for them to happen, particularly under full power. Just blew up a turbo and don't want it to happen again. had two .073 jets with bottle pressure at 950-1050 psi. was going good in 2nd gear seemed to blow up either on or right after the third gear change.

have nx boost referenced controller that was not on at the time, instead they both came on with a switch. was real fun until it blew. compressor wheel all mangled up and turbine wheel gone. was hoping to use my system at full capacity which is 2 .125 solonoids. so the .073 was just a bit over half way.
nozzels are in bottom of intercooler shooting straight up into endcaps on both sides on intercooler.
 
Mine back fired when I hit both stages at the same time on the dyno with out enough boost. Just make sure you got enough rpm rolling and enough boost built before you hit it.
 
Like said above where you running a gate? No matter what turbo when I prayed n20 I would have my gate set at 40psi
 
From what i understand it pushes the wheel or forces it hard in the bearing.I think your spraying it to hard.Two .73's is alot of smack.
 
had ED 50mm gate set at around 55psi-58psi.

I think your spraying it to hard.Two .73's is alot of smack
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Are you saying that two .073 hitting at the same time is too much or just running two .073's at all is to much in any form?

No matter what turbo when I prayed n20 I would have my gate set at 40psi
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Why? what if you had twins, would you set them that low as well? does this have to do with compressor efficiency or just over all boost.
 
When I would spray mine hard with a single I would set it low as long with twins,It seems to make everything live and also it did not loose power on the dyno when I would run lower boost with nos. Two jets like you are running would be better to spread out instead of them both coming on at the same time.
 
If the turbo overspeeds and blows up, then the nitrous will most likley backfire too. I got pissed off a few days ago and hit two .135 jets at 15psi and it popped, but kept going, and no damage. Boost was wastegated at 35-ish on fuel, and hit over 50psi on the spray. Nitrous creates tons of drive pressure.
 
Too much fuel or not enough fuel putting flame out? You spraying before or after the intercooler?
 
Trainrobber said:
Too much fuel or not enough fuel putting flame out? You spraying before or after the intercooler?[/QUOTE]

gs1000 said:
How do they occur? what conditions must be present for them to happen, particularly under full power. Just blew up a turbo and don't want it to happen again. had two .073 jets with bottle pressure at 950-1050 psi. was going good in 2nd gear seemed to blow up either on or right after the third gear change.

have nx boost referenced controller that was not on at the time, instead they both came on with a switch. was real fun until it blew. compressor wheel all mangled up and turbine wheel gone. was hoping to use my system at full capacity which is 2 .125 solonoids. so the .073 was just a bit over half way.
nozzels are in bottom of intercooler shooting straight up into endcaps on both sides on intercooler.
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If the turbo overspeeds and blows up, then the nitrous will most likley backfire too
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I can't really pinpoint what happened first. I don't know if the turbo let go and the charge then got into the hot exhaust and then fired which might explain the grenaded turbine wheel. Or if the the nitrous backfired through the intercooler which is also now broke and leaking which caused the compressor wheel damage. The compresserr wheel is broken off the shaft.

Too much fuel or not enough fuel putting flame out
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with 2 .062 jets i still had smoke, not crazy thick but black and quite a bit. so i increased my fuel via fuel plate towards front and put in the .073 jets.

Two jets like you are running would be better to spread out instead of them both coming on at the same time
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I think that the boost referenced programmer thing will help with this a lot. hooking it up today.
 
ok here is my input.. the turbo blew up first and my reason for that is first off running your single up to 55+ is overspeeding it. Second you have it overspeeding then cool its charge down so now its trying even harder to fill that space.. = more speed. Second adding that much smack to it drives the turbo even harder creating even more speed. Its to much and thats why you had an overspeed explosion.. Also this is why twins dont blow as easy. they continue to heat the air so dont commonly overspeed as easy if they are settup correctly. Secon thats why everyone Ive ever helped set up their no2 decreases their boost to make the turbo live..
 
Not trying to highjack the thread but i was wondering would a external wastegate lower the risk of a back fire ? Im not spraying until I have get one lol
 
benstrokinnowcummin08 said:
Not trying to highjack the thread but i was wondering would a external wastegate lower the risk of a back fire ? Im not spraying until I have get one lol
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Not so much, nitrous back fires usually encounter when there is not enough fuel for the amount nitrous spraying. Even with a wastegate it can and if the wrong mixtures of nitrous and fuel are present, it will happen. Usually blowing through the weakest point whether it's the head gasket, sheet metal intake, turbo, etc. It will usually throw a very nice flame.

We had the wrong fuel set up last year in the altitude of Denver and first hit... BOOOM! The track starter jumped about 3 ft in the air :hehe: I was on the inside and my ears were ringing for quite some time!
 
alexlaughlin said:
Not so much, nitrous back fires usually encounter when there is not enough fuel for the amount nitrous spraying. Even with a wastegate it can and if the wrong mixtures of nitrous and fuel are present, it will happen. Usually blowing through the weakest point whether it's the head gasket, sheet metal intake, turbo, etc. It will usually throw a very nice flame.

We had the wrong fuel set up last year in the altitude of Denver and first hit... BOOOM! The track starter jumped about 3 ft in the air :hehe: I was on the inside and my ears were ringing for quite some time!
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Ok that makes sense lol thanks alex you da man I just want to hit 800hp with spray and call it good weather its with my 66mm silver bullet or hopefully ill be able to get a s400 to put on the bottom of the 66mm and see what it does heres a video of my truck alex im sure you will remember my truck lol

http://www.youtube.com/watch?v=82VAAdsnlHs&playnext_from=TL&videos=Bgs1h1k88Is
 
Silver bullet + a decent sized shot of nitrous(with no progressive controller) = kaboom
 
benstrokinnowcummin08 said:
Ok that makes sense lol thanks alex you da man I just want to hit 800hp with spray and call it good weather its with my 66mm silver bullet or hopefully ill be able to get a s400 to put on the bottom of the 66mm and see what it does heres a video of my truck alex im sure you will remember my truck lol

http://www.youtube.com/watch?v=82VAAdsnlHs&playnext_from=TL&videos=Bgs1h1k88Is
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I have ran a million trucks on the dyno and yes I remember that truck, I was impressed by it!
 
I apperciate it alex coming from you that means alot to me my name is mark by the way my first diesel which was a 6.uh oh lol is in diesel power mag when yall had that free dyno night. Anyway back on topic I agree with you WUnderwood on the no progressive control = boom so I will be sure to have one when I spray thanks for a info yall.
 
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