Honda / Acura K20a K24a Engine Forum banner

nitrous setups

42K views 168 replies 51 participants last post by  LotusElise  
#1 ·
what is the biggest nitrous shot that has been put on stock internals before they break? what is the most reliable setup that everyone has been using? direct port injection or just spraying into the intake tube? dry/wet? etc. i tried using the search feature, but came up with nothing. if anyone has a thread link or some info, it would be appreciated.
 
#2 ·
direct port is safer since each cilinder is getting the same amount of nos. now on the shot size I'D like to know too what is the max each engine can handle
ex
k20a :??? shots xxx HP stock internals.
K20a2:??? shots xxx HP stock internals.
k20a3:??? shots xxx HP stock internals.
K24a1:??? shots xxx HP stock internals.
k24a2:??? shots xxx HP stock internals.
k24a4:??? shots xxx HP stock internals.
 
#8 ·
i would be careful with that dude, you would already have alot of pressure in the cylinders with that compression. maybe with some new head studs and a better head gasket you might be ok, but forced induction is not my area at all.
 
#10 ·
How safe is it to actually run a 70 shot (wet or dry) in a stock k20a2 with a stock jdm type-r ecu? Anyone have this setup for a while and by a while I mean for a year or two. I know nitrous destroys your internals eventually.
 
#14 ·
i would really like to know if anyone has tried to blow up their engine with nos to see how far the stock internals will go.

a guy down here used to have a type-s turbo with the greddy kit and he pushed it hard till the stock bottom end blew. i want to say it was 18-20 psi of boost before the #3 piston cracked and destroyed his motor. but then again,he was loaded and he was just doing it to justify buying new parts.

i have been told 50-75 shots of nos are around 10-11 psi. i would like to hear from some of the engine experts on this to see if they could give the chamber pressures before things start messing up..
 
#15 ·
i thought that 10 shots = ~1 PSI of boost..
there was a guy here running a tunned rsx type-s with 125 shot direct port wet for 1 full year and then he bought ITbs and cams and went allmotor with the stock bottom end.
the motor was running strong, but i forgot his user name.
 
#16 ·
that's what i had heard, didn't know if it was fact though.

you said 125 wet shot direct port on a stock bottom end with no problems? wow, i thought the max would have been 100 at best. was it his daily driver and do you know how often he sprayed?
 
#17 · (Edited)
#18 ·
yea that setup was fun.. pretty basic wet shot... added like 3 or 4% fuel in kpro and it was great i also had it pull some timing.. i dont quite remember what it was set at as it was a while ago.... it was at a 80 or 85 shot i cant recall exactly as i forget the jet sizes.. but it was one of the 2. i also ran i think they were plugs that were temp 9.. compared to the stockers that are 6s


i sprayed a lot of times.. id say i went through 5 or 6 10lb bottles


if you treat the car right and dont be stupid about it it will last a long time.. my motor still is perfect to this day.. it runs absolutely awesome and has perfect compression and doesnt burn a drop of anything..


like i said mine wasnt even tuned but i made sure i had the fuel i needed and just keep a good close eye out for anything and be smart about it.. im sure a stock K on a tuned (AND I EMPHASIZE TUNED!)dry shot can handle probably 100 - 150 and be reliable.. but thats if you keep your head on your shoulders about it..

make sure your keeping your botle pressure constant from when you tuned it to when you use it..make sure your plugs are always in spec and look nice. etc..


but yea.. 85 shot is plenty..i went 12.20 at 115 on drag radials with only a 1.9 60 ft with that simple setup(no bottle warmer no purge, etc) and let me tell you the car was quick.. it would have went 11.60 at least on slicks.


hopefully that helps some of you... and if not.. then feel free to Pm me about your questions or comments.
 
#19 ·
I have a zex dry kit I'm getting ready to install and on my b series I had to hook a vacuum line from the box(solenoid) to the fuel psi reg. do I need to do the same on the k series. I know all motor you don't need the vacuum line but should I hook it up for the n20?
 
#20 ·
1992 EG hatch
K20A3 Swap
DC Header
S2 Exhaust
Ebay SRI
NOS Holley Wet Kit
Kpro

Factory motor.

I tuned this car yesterday on our dynojet with a 100shot. Car off bottle was tuned to make 163hp and 134lbs of torque.

on bottle it made 253hp and 219lbs of torque.

Better part is, we didnt connect the kit to the kpro. All we did was use the map on the kpro to take about 3 degrees of timing out. Although the kpro thinks its activating the nitrous its not. Its a failsafe way of making sure it never goes lean.

Car hauls like you wouldn't believe. Ran 12.4 on street tires with a 2.23 60ft last night.

Those motors can hold 125 factory. Just do it right, long as she has gas, your good. Dont be scared, spray away
 
#24 ·
In my K24A1/K20A2 CRX, I am now on a dual stage set-up. First stage is a ZEX 75 wet shot in to the intake tube. Second stage is a ZEX 150 wet shot direct port. Thursday night, I ran a 7.5 at 97 mph in 1/8 mile. The motor is internally stock and loves the nitrous. It made 314 whp and 305 ftq on my dyno (DynoDynamics). The horsepower curve went nearly vertical! I have made about 70 passes on the bottle, this year.

My K20Z1 Integra with a JRSC at 9 psi is now also on a dual stage ZEX set-up (again, wet). First stage is a 65 shot and second stage is a 125 shot. Last Thursday, the Integra ran a 7.6 at 94 mph in the 1/8 mile. Last night, it ran 11.7 at 119 mph in 1/4 mile. The motor is also internally stock and also loves the nitrous. It made 354 whp and 264 ftq on my dyno. I estimate that I have made about 80 passes on the bottle, this year.

The key is careful tuning. Both cars have the nitrous controlled by KManager. My nitrous tunes are conservative and use the KManager safeguards to the fullest.
 
#30 ·
Jesus, I didn't know that stock a2 blocks can handle 125 with just an ecu tune!

Not to mention all the power you are making from the nos, this is outrageous!

I am assuming that if the bottom end was built with some off the shelf parts, you could hit a 175-200 shot of nos. Maybe even some new head studs to be safe.
 
#25 ·
Holy Crap:wow: You guys are really making some power on the stock blocks.
I have a question though, when is it optimal to spray, RPM and Gear wise?
I reckon having the spray continue between shifts is bad, so do you do an RPM or clutch switch cut off?
 
#29 ·
I spray around 4500 and spray til about 8-8200 (55 shot) in 2nd gear and it feels like it'll break my tires loose but it just pulls. I have mine hooked up to my horn buttons so its right on my wheel and easy to push while racing. Dont really like those full throttle switches because if you miss a gear and hit the gas :down:
 
#26 ·
I had a wet 75 shot on a stock b16. I ran it for about a whole year. I would go through a 10 pound bottle once a week, sometimes every otha week and neva had a problem with it. I always sprayed right off the line all the way to 4th gear. I always took care of the motor though. Gave it a oil change every otha week and used cold ngk spark plugs every week. The only time i broke somethin was at the track but thats cuz i over heated the bottle past 1500psi. I say a strong and safe psi is 1200. Ne thing past that is a lotta pressure.
And about when to spray, thats up to u, i wouldnt spray on first or even second with a k series, u already spinn like crazy, u just have to learn and play with it a bit.
 
#27 ·
I am constantly experimenting with my laptop at the track; therefore, what I am about to write may change again. But, it is working really well, right now.

In KManager, I set the rpm window from 3,800 to my shift point (7,200 in the CRX and 8,200 in the Integra). I set the load engagement to 86 Kpa and throttle percentage engagement to 85 (full throttle). This way, I am not spraying during shifts and if something were to go wrong, it will stop spraying. In addition, since I am spraying wet shots and adding fuel in KManager, if the nitrous flow is unstable (for any reason), it will go super rich instantly and I know right away (massive black smoke from the tail pipe and a huge drop in power/torque). In my street cars, I have wideband gauges to help me keep an eye on conditions.

What I change all the time is the mph windows. This will depend on traction at the track, temperature, etc. I start stage 1 at 12 mph until 35 mph and stage 2 engages at 36 mph and up. Basically that means that I use a small shot (65 or 75) in first gear, right after I get off the line. I use the larger shot (125 or 150) coming on in second gear all the way through fourth in the 1/8 mile and fifth in the 1/4 mile. That only works for me on slicks and I run either 24.5x8 or 24.5x9 slicks. On drag radials, all of this is pointless, because all I do is spin. I only spray on the street if I am doing a demo for a customer and that is rare and useless. I literally smoke the tires through all the gears.

Finally, with regard to bottle pressure, the best solution (albeit expensive) is to put a nitrous pressure regulator right before the nitrous solenoid. I run one on my CRX, I set it at 900 psi, and it keeps it there (that is the recommended, optimal nitrous pressure for best results) . You will feel and hear the regulator working at the track! It literally pulses your engine with the nitrous flow as it tries to compensate for the fluctuating bottle pressures. This is disconcerting at first; however, it works great for me! Be careful in winter time, the cold temperatures play absolute havoc on your bottle pressure (I have lost a half a second in the 1/4 mile because the pressure dropped too low on a cold bottle).
 
#28 ·
By the way, there is a ton of great information about nitrous on here. Here is a sampling:

http://www.k20a.org/forum/showthread.php?t=11601

http://www.k20a.org/forum/showthread.php?t=8070

http://www.k20a.org/forum/showthread.php?t=19498

http://www.k20a.org/forum/showthread.php?t=28796

http://www.k20a.org/forum/showthread.php?t=30213

Oside JimC's sticky is mandatory reading in my opinion. He has gotten his built K24 down to flat 11's already (in a full interior RSX)! I am dreaming of spraying a 250-300 shot on a built motor :). Right now, I believe I am going to keep mine where they are at, since I am still on stock internals. Besides, if I go much faster in my street cars, I need to put in roll cages.

For reference, all of this is peanuts to the domestic crowd. Here in South Carolina, I run against muscle cars spraying 250-300 shots with carburators every week. They run 5's on built motors and 7's on stock motors (in the 1/8 mile). Years ago, in high school, I ran 11.1's in the 1/4 mile with my 4-barrel carburator Mustang on a LARGE shot of nitrous (ancient Holley set-up). :D
 
#31 ·
I was at the track last night and saw ronald run his beautiful full interior GSR consistantly.... Ronald mad props :up:

Makes me want to throw some nitrous on my k24 build.
 
#32 ·
man i'm like :wow:
i was planing on taking a change with a 2 stage set-up 66 on the 1st stage and 88 shot on the second stage, that would be a total of 154 shot, but after seeing that you are putting 75+150=225 shot on the stock K24A1/K20A2 CRX and 9 psi boost + 65 + 125 = 187 shot on the stock k20z1 integra:wow: then i i think that my set up may be ok :confused:.

now i have a (1) wet nos 4 fogger direct port system and i was thinking of putting nos where the fuel pill goes.
so that would make my kit a 2 stage dry kit and tune it with k pro with 650cc injectors.
don't know if there would be a nos flow issue since i would be spraying where the fuel jet should be?
another thing i was planning on using 2 separate bottles one for each stage.
the reason i want a 2 satge is because i had a stock b20V on a single stage 140 shot wet direct port making 264whp 244 wtq and that sucker did not move in the lower gears it used to spin too much, but once it had traction it was out and it lasted 3 years. i can't even count how many bottles i used.
 
#34 ·
after seeing that you are putting 75+150=225 shot on the stock K24A1/K20A2 CRX and 9 psi boost + 65 + 125 = 187 shot on the stock k20z1 integra
:) Whoa, not too fast. I have not combined the two stages yet. I want to, but I have not had the guts to do so, yet. Remember, I wrote that stage 1 goes to 35 mph and stage 2 starts at 36 mph. I agree with you, that is the way to go, but all year, I have been gradually increasing the nitrous, re-tuning on the dyno with every change. Running a combined 225 shot of nitrous on the stock K24 block is still a little ways off.
 
#35 ·
for some reason i thought that you were adding the second stage, but my brain was saying like that's too much nos for a stock motor to handle. that's why i wrote it like that 1st stage + second stage so you could clarify things :up:
 
#38 ·
I have a
k20z1
dc header
3inch exhaust
80 shot NOS wet direct port
Tuned with AEM.
I have been spraying on my motor for over a year and my motor and I love it. The car made 203 n/a and made 275 on spray with no tunning. I'm about to up it to a 125 shot soon.
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