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Discussion Starter · #1 ·
Hey guys... haven't seen a post on this, and I'm really wanting to know disadvantages of NOS-- specifically the "Venom NOS" system, found at http://www.venom-performance.com. I would have either the turbo system (by Thomas Knight) or Venom NOS system professionally installed. While I know that an improperly installed NOS system can be lethal to the car and driver, if installed by someone "in the know" are there any other disadvantages? Turbos are pricey, and also need to be installed correctly, whereas of course NOS is extremely cheap in terms of $$ per horsepower gain. The Venom NOS is just over $400 plus installation. How much should installation cost for a 50 or 75 shot system, and am I asking for trouble? If a turbo would be more reliable and trouble-free then I would consider springing for it. I would like my '96 2.5 to be really quick, but also want to maintain its reliability. Any info would be greatly appreciated-- I know virtually nothing about turbocharging or NOS, other than what I've read. Thanks!
 

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stick to the turbocharge option for now and forever. u can wean the NOS system later on down the track. by the way the consequences for accidentally turning your car off straight after a run with the turbo is at most a loud pop of unburnt fuel providing you turn the engine back on straight after. the the consequence for shutting the engine down whilst your nitrous is engaged is..i quote from OZNOS sytems"YOUR ENGINE WILL EXPLODE!!!" think about it!
 

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go with the turbo, the nos is good for the track i guess but i dont even like it there i rather have all engine power my self, but my car is all show no go
 

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but dont let that put you off.only idiots shut there engines down with both triggers on and if you dont install it right you can have a sticking switch. the advantges are obvious though and i anticipate installing my own on my 91gt.you get about 4and a half minutes of go time per bottle. and you need to properly adjust the fuel and nos solenoids. i have driven a bmw m3 with nos and i understand why u want one.tho my friend fitted one to his 944 turbo porsche and after the 2nd go his valve assembly on top of the bottle started to leak. we pulled over straight away and threw a cloth over the valve and quickly disconnected it. quite scary! his car under full revs with nos tripped(as u can only trip nos under full throttle) sounded like a bombed out wrx crossed with a landing plane...we shot white flames out the exhaust for the length of time nos was on!!!
 
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Discussion Starter · #6 ·
c'mon nitrous supporters

look im also intersted in installing a Venom nitrous system,
i own a 97 2.5 with only 80 000 k's on it,
goin to do a compression test, phenolics, valve gasket etc.

is there any one out there that can tell me if i need a fuel pump or no? ps i am content to run only 50 shots.

or give any advice, it was this or a turbo.
but the turbo seems to be to ongoing and too much bullshit!!

Also any xtras that would be suggested? such as a blow off for the bottle or other saftey features??

anyone that has a 2nd gen on the bottle please give me a buzz, i'd really appreciate your experience!!!

thanks in advance,
stylez
 

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tomsmx6t91 said:
by the way the consequences for accidentally turning your car off straight after a run with the turbo is at most a loud pop of unburnt fuel providing you turn the engine back on straight after.
unless you listen a little closer. you will hear the damn thing sizzling. real hard on the main bearing, both turbines, etc. turbos generate extreme heat and NEED a cooling off period. without lowering your compression, you will not be able to run high boost. you will just have a light pressure setup. my friend blew the engine on his avenger with an intercooled turbo and timer. just the pressure took it out after a while. and you have to wait for the turbo to spool up. and with stock pistons, you probably wont get more than 20 HP. add an intercooler for more $$$ and maybe get 25 or so. or you can get your NOS for a LOT cheaper. respect it and is will respect you. on a stock engine, dont run more than a 100 shot, dont hit it below 2K RPM, above 6K RPM, unless youre at full throttle, unless the clutch is fully engaged, for more than a few seconds. and the power is there instantly! no spool up time. power at the touch of your finger. but either route, you should at LEAST put in new pistons. and if you have enought money to spend on a turbo/intercooler, you should just build your engine up to a stage 2/3 and still have more power than a turbo. then you can add 150-300 shot of NOS with no problems should you feel the need for more power.
 

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JspecMX-6 said:
without lowering your compression, you will not be able to run high boost. you will just have a light pressure setup. my friend blew the engine on his avenger with an intercooled turbo and timer. just the pressure took it out after a while. and you have to wait for the turbo to spool up. and with stock pistons, you probably wont get more than 20 HP. add an intercooler for more $$$ and maybe get 25 or so. or you can get your NOS for a LOT cheaper. respect it and is will respect you. on a stock engine, dont run more than a 100 shot, dont hit it below 2K RPM, above 6K RPM, unless youre at full throttle, unless the clutch is fully engaged, for more than a few seconds. and the power is there instantly! no spool up time.
A few points:

1) Stock KL03s can get far more than just 25HP from an intercooled turbo setup. Allan Wong was putting 225HP to the wheels in his stock-internal turbo KL03 626 at 9PSI or so. A stock KL03 is putting 135 to the wheels so he's approaching 85HP more than stock at the wheels...probably more than 100 at the crankshaft. And it was doing this reliably (though he was probably nearing the limit of the pistons and rods.)

2) Nitrous power may be instantaneous (which isn't necessarily always a good thing in terms of thermal & mechanical shock to the engine and also traction issues) but (a) the fun is over when the bottle is empty and (b) ask anyone who uses their nitrous with any regularity how much of a pain in the ass it is to continually get the bottle(s) filled up.

There are elements of danger associated with carrying a 1000PSI bottle in the trunk as evidenced by the now-famous pics seen here:

http://www.enhancedhealth.com/NOS2.htm

This one, http://www.enhancedhealth.com/pict532.jpg, is one of my favs :)

There may be legal issues in the local area about carrying pressurized bottle of gas in the vehicle. A turbo might get you some grief come emissions-test time but a cop inspecting your trunk might actually charge you with an offense. I'd check local regs before considering N2O.

That Avenger motor probably blew up because the owner probably "got used" to 7 or 8 PSI and decided he wanted a bit more. Then a bit more. Then a bit more. And before he knew it, he was running over cast aluminum shiny parts. The same will happen with nitrous: a 50-HP shot won't be enough after a week and in goes the 75-HP jets. Then the 100-HP jets... "Operator-induced boost creep" I call it :D Self discipline will go a long way to ensuring engine longevity with either option.

IMHO, if the choice is between turbo or nitrous (the cost disparity notwithstanding), I'd choose the turbo.
 

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You don't have to be an "idiot" to turn the motor off while NOS is on -- stalls happen. Normally stalling is harmless and just annoying, and it can happen for any number of reasons (including the infamous ignitor module failure). It is a little hard on a hot turbo, but not immediately fatal. With NOS, if you happen to be "on the juice" when it happens, BOOM. Unlikely perhaps, but unlikely things become a lot more likely on a modded car. Also, fuel delivery on a NOS system is a complete hack and always will be -- just dump in lots of fuel and hope that your A/F ratio is about right. With a turbo, there is some attempt made to determine the actual amount of air entering the engine. And those flames shooting out the tailpipe might look cool but they aren't doing anything good for the car (O2 sensors, catalytic converter, the paint on your bumper, or the guy behind you!).

About that turbo'd Avenger: that engine was either 9.6 or 9.4 to 1 compression (i.e. higher than the KL03), and whose knows how good his boost control was. A poorly setup system can suffer from boost creep (possibly operator induced :) ), or spikes well in excess of the wastegate setting. We also don't know how good his fuel system was -- its easy to do fuel delivery badly and not find out until you bounce off the rev limiter and the fuel pump wigs out. It is impossible to draw conclusions from one bad custom turbo job, especially on a different kind of car!!

The stock KL03 internals have been demonstrated to hold >9 psi, and even without intercooling you can manage up to 8 psi without detonation (if you can run rich enough). I can tell you from first-hand experience that the "wait" for the turbo to spool goes by very quickly; at launch it is about the only chance you have to get traction! And I've got fairly big turbo (T04E). On the freeway there is no wait, boost is there the instant I put my foot down. Plus I don't have to put my foot to the floor -- the turbo gives more power on partial throttle as well, and it will last through a whole race without switching on and off. If you care about more than driving fast in a straight line for 1/4 mile, then don't get NOS.

Personally I'm partial to a turbo (obviously), but no matter which route you take this is a major modification to the car and you'd better make sure its done right. Cutting corners, taking half measures, and pushing the envelope will grenade your engine. If you do it right though, its a whole lotta fun. :cool:
 

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being the cheap bastard that I am, I'd say NOS is the ticket. but listen to this movie http://www.probesnw.net/movies/snow16bit.avi and tell me again you don't want a turbo.

NOS may give you better numbers and performance for any parcitular car, but I think a turbo will give you a better car overall. if you can afford it, turbo's the only way to go.
 

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azl said:
if you can afford it, turbo's the only way to go.
now you guys now how i feel about this one... $5000 for a turbo? for 40-100 HP? or dropping $5000 and some sweat and blood into the full engine. to gain 150+ HP. those pics of that explosion were pretty painful, and it happens but i wouldnt say its a frequent occurance. the avenger turbo was professionally installed and he had a boost controller. im not sure if he had "boost creep" but i wouldnt be surprised. i neglected the fact that he has the KL. the avenger was a 4 and i dont think the FS draws enough air to take 9 PSI. but you guys (mike and asword) know more about turbos than me so lemme know if im wrong. once you have the turbo though, how can you improve on it? change a 7 spline turbine to a 9 spline turbine? i just favor the built engine. you can drop the same amount of money for more power. and whats even better, you can build on it when you get more money. charge it, NOS it, etc. and the engine can handle it with no problems. but running these items on a stock engine is askin for it. like i said, respect it and it will respect you.
 

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JspecMX-6 said:
now you guys now how i feel about this one... $5000 for a turbo? for 40-100 HP? or dropping $5000 and some sweat and blood into the full engine. to gain 150+ HP. those pics of that explosion were pretty painful, and it happens but i wouldnt say its a frequent occurance.
True. But "sh*t happens":

- accidentally leaving a bottle heater on or having a relay fail "on" can lead to the type of occurence seen in those pics
- a leaking solenoid can allow the manifold to fill with N2O, which can lead to a manifold explosion if the car backfires. I've personally seen intake manifolds broken at their mounting bolts and lifted off the heads by this problem (albeit on V8s...)
- a rear-end collision can lead to a ruptured N2O tank which can make a small fire a big deal with all that liberated oxidizer around
- an ignorant mechanic working on a car can forget to install NOS jets correctly leading to potential engine damage as the driver unknowingly sprays.

Personally, I think there's just too much that can go wrong with N2O, too many avenues for something to happen that makes the long-term risk outweigh short term benefits. Having said that, there are lots of careful people out there who run N2O, and have done so for a long time, with no problems. I don't think however that their diligence & self-discipline are representative of the populace at large. IMVHO.

i neglected the fact that he has the KL. the avenger was a 4 and i dont think the FS draws enough air to take 9 PSI. but you guys (mike and asword) know more about turbos than me so lemme know if im wrong. once you have the turbo though, how can you improve on it?
The amount of boost pressure isn't so much determined by the displacement or number of cylinders but by the turbo and control mechanisms (e.g. the wastegate). 25PSI 1.6L Honda drag motors aren't unheard-of nowadays. They run huge turbos and take a few seconds to build boost, but they do it.

As far as improvements, it depends. A stock-internal V6 is safely limited mechanically to maybe 9PSI. But at 9PSI, you're making 270HP or so at the crankshaft, giving the 2800-lb MX6/PGT the power to weight ratio of a 350HP, 3550-lb Z28. Getting that power to the ground through a FWD powertrain is the concern of course, but it'd be a lot of fun trying :)

That's pretty respectable output. If you still want more, then you'll have to build the motor internally. Allan Wong did this with his stroker KL03 and put over 300HP to the wheels (though the clutch was slipping badly and he aborted the run.) But he's got a ton of money, blood sweat and tears in that 626 of his. "How fast do you want to go? How much money do you have?"

With the motor built like this, the limit becomes other driveine components: lack of an LSD hurts the ability to put power down. A Quaife LSD is available but it's not cheap. The clutch and transmission is also a concern and so on down the line.

i just favor the built engine. you can drop the same amount of money for more power. and whats even better, you can build on it when you get more money. charge it, NOS it, etc. and the engine can handle it with no problems.
Well...

First, you have to decide what you're building the motor for before you can say you can "charge it, NOS it etc". A small displacement poppet valve piston engine (2.0L let's say) is never going to move alot of air on it's own unless it revs like crazy. A Honda S2000 is a good example: 240HP but near 9000RPM. You'll never hear about an engine that size making 300HP at 5500RPM without some sort of artifical respiration.

Further, if you want to start out with a high-RPM screamer making tons of HP at 7500RPM, then you'll need camshafts and compression designed for it. But those same cams and especially that compression probably won't work well for adding a blower or N2O later. High-RPM cams tend to have quite a bit of overlap which can work against forced induction (Oscar Jackson said as much about the 1.6L 160HP Civic Si motor) and high compression increases the likelihood of detonation. Most motors designed with turbocharging in mind run around 8:1, not the 10:1+ N/A high-po motors will run. You can put blowers on these engines, but you'll not be able to run alot of boost with them and they won't be optimal.

IMHO, if you're purpose building a motor, start with a definite plan: high RPM, normally aspirated, or high-pressure turbo, N2O etc and build it to optimise that plan.

but running these items on a stock engine is askin for it. like i said, respect it and it will respect you.
Definitely. Any power adder like a blower, added to a stock motor, moves the envelope of operation closer to the "red zone" of relibility of stock parts. All engine parts are designed with "safety" factors, but they're designed with the OEM power output and mass manufacturing processes in mind. Once you increase that substantially, the loading gets closer to the limits the part will take. Who knows, some KL03s might have rods with minor internal defects that will last forever at 164HP but which will break at 270HP...
 

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I would be surprised if $5000 would get you more power than a turbo would -- nor would it be such a polite engine after you are done. When you're not on the boost, a turbo'd engine is pretty much stock. A heavily rebuilt engine is going to have permanently modified behaviour (e.g. poor idle and fuel economy). Of course if you rebuild the engine and then turbo it you'll really develop a lot of power -- although fuel delivery and traction are tough to sort out.

If I understand what you're saying about the Avenger, then it was the 4 cylinder 9.6:1 compression engine and he had a small turbo. The small turbo would lose efficiency at higher airflows and heat the air excessively. If the intercooler was undersized, poorly placed, and/or the weather was hot, then this would cause very high cylinder temperatures and pump gas would almost certainly auto-detonate -- destroying the engine in short order and irrespective of ignition timing.

If you choose the right turbo then you don't ever need to change the turbo, it will be able to deliver all the air the engine could ever need. You can just adjust the wastegate to increase boost (otherwise known as operator induced boost creep). The major issue on the KL engine is delivering enough fuel to prevent leaning out and keep combustion temperatures down. These engines primarily die from melting, not blown pistons or bent rods. Even if you go and rebuild the engine, a turbo is more than capable of destroying it if not tuned properly.

This is not an either / or proposition: you can have a turbo and still make airflow and structural improvements to the engine. You can even bolt NOS onto a turbo'd engine; this is sometimes done to cover the lag of really large turbos.
 

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Mike 94PGT said:
All engine parts are designed with "safety" factors, but they're designed with the OEM power output and mass manufacturing processes in mind...
may i add reliability and efficiency... very informative posts...i appreciate that.

So... the guy at my local speed shop said that if i wanted to run NO2 that he would put me on a gradual setup starting at about 50 or 75 HP, to ween the engine and to get me used to the feel of NO2. he told me that i would need an LSD. this may be 6 months or even a year down the road so im not too concerned with this yet, but... how much is an average LSD? and how much fun am i gonna have installing it? trannies arent my favorite area of the drivetrain...
 

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totally off topic...sorry

tlk... I am a student at Texas A&M and am about to get my CCNA. I read your homepage and if the link is right it said you have one. Is the exam tough?!!! Just curious what I'm up against. But it would look great with the my when I graduate. For everyone else, I am so sorry to waste your time with Telecomm stuff but I had to ask...SO SORRY!!!
 

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why all this talk about NOS and turbos? it costs a lot less to get a KLZE than a turbocharger. but if money isn't a factor, a SUPERCHARGER is way better than a turbo anyway, in my opinion...
 

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asso said:
why all this talk about NOS and turbos? it costs a lot less to get a KLZE than a turbocharger. but if money isn't a factor, a SUPERCHARGER is way better than a turbo anyway, in my opinion...
Because a KLZE has roughly 35HP more output over a KL03, assuming one can properly get the PCM/VAF issues worked out. A close to stock (bolt-ons like CAI, headers etc only) KLZE usually turns in the area of 170HP to the wheels.

A turbo, OTOH, will crank a stock-internal KL03 up to 270HP from 164 and puts a solid 230-240P to the wheels.

So if you can live with 70Hp less, go with the 'ZE.

And why, out of curiosity, why would choose a s/c over a t/c?
 

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Please respond to this...

Why can't you s/c or t/c a KLZE...if that's possible then you are still in the same boat with the KL03 being out performed by the ZE...and I would also s/c over t/c. The reason is the power is there from the get go. You have no waiting period for extra horses. Turbo's have to spool up before they kick in thus the phrase turbo lag (i think that's where that comes from). The only draw back to a s/c is high end power. If you want to increase top speed t/c, but if you want a better quarter time then s/c. That's my opinion so if it is flawed please point it out to me...nicely!
 

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Re: Please respond to this...

aggiedj02 said:
Why can't you s/c or t/c a KLZE...if that's possible then you are still in the same boat with the KL03 being out performed by the ZE...
The KLZEs higher compression (10:1 versus 9.2:1) limits the amount of boost you can run on it before detonation sets in. Also, the rods in the ZE are no stronger than the KL03 and the pistons are still cast aluminum and just as weak when subjected to severe detonation.

Certainly, you can put a blower on it and probably run, say, 6PSI on it. With the better breathing of the KLZE's intake and cams etc, I'm sure it would end up making a few more HP than a KL03. But is that worth the cost of getting a KLZE and then putting the blower on it? I don't know...

If I was dripping money, I'd take a KL03, build it like Allan Wong did and put an 18PSI turbo on it; more than 300HP at the wheels :)

and I would also s/c over t/c. The reason is the power is there from the get go. You have no waiting period for extra horses. Turbo's have to spool up before they kick in thus the phrase turbo lag (i think that's where that comes from). The only draw back to a s/c is high end power. If you want to increase top speed t/c, but if you want a better quarter time then s/c. That's my opinion so if it is flawed please point it out to me...nicely!
No flaws...everyone has their opinion. For me, the size of a turbo that you'd typically put on a stock-internal KL03 (which is strength limited to low-to-moderate boost levels which would require a fairly small compressor) would mean that lag is virtually non-existent. Andrew B., I think, has said this before with his 93PGT turbo.

A agree with the s/c power limits. The boost on a s/c is largely determined by the shaft speed which is determined by RPM. It's nice and linear, but a compressor set up to deliver good boost at low RPM might turn inefficient and worse, may heat up the air excessively, at high RPM. As well, I've yet to see a s/c installation that didn't look like a complete hack from the point of view of the compressor drive. The idea of that long shaft spinning across the front of the engine just isn't appetizing to me from practicality and reliability viewpoints.

To each his own I guess :D
 

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nos or turbo

Well fellas if I may interject for a moment. For all you out there considering nos. don't do it especially if you have fairly high miles on your car. I had it on my car until 4months ago I have high miles. Was at the track in vagas with a friend he had it on his civic and his second time down the track. Boom!!!!!! granted the turbo/sc will be more expensive at first but just think you will still have a car and your life in the end. Stay off the laughing gas.
 
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