3rd Generation Specific (1993-2002) 1993-2002 Discussion including performance modifications and Technical Support Sections.
Sponsored by:

question about nitrousoxide...

Thread Tools
 
Search this Thread
 
Old Mar 31, 2006 | 03:31 AM
  #1  
bheiman's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Jul 2005
Posts: 256
Likes: 0
From: omaha
question about nitrousoxide...

Nitrous has been on my car, even before i got it. It keeps irritating me that i have something that is ONLY for show on my car.
I have contemplated taking it off, but never do.
I believe it is only a 35(wet) shot. operated by TPS I will check the pills tomorrow...
http://681network.com/rx7pics/fd1.jpg
you can see how it is setup there.

i do have a question. Has anyone actually ran nitrous on their car. I just want to try it once at the strip just to see how much a difference it will actually make.
Im thinking because of the air cooling effect plus the effects of N20, i think it should be a ~50 hp gain.
Right now im running 12 psi.
I was thinking of dropping to 10 psi and running the nitrous shot. I drove around with a wideband at 10psi and my afr were ~11.1 so at no point i am leaning out.

Honestly if i were to use it, would i have any substantial chance of blowing the engine? (it has ~16k on it)

Couldnt i put in a bigger fuel pill to richen it up for safety? Maybe even run 12 psi and run more fuel?

I dont want anyone to just say. NO IT WILL BLOW cause i know people are running it. I just wanted to try it on a run to see what it would do.

DISCUSS
Reply
Old Mar 31, 2006 | 11:51 AM
  #2  
BobfisH's Avatar
RX7 lover
Tenured Member 05 Years
 
Joined: Jun 2005
Posts: 1,160
Likes: 3
From: UK
A wet kit injects fuel and nitrous at the same time, so no worries about leaning out (provided your pump can flow enough to maintain fuel pressure and the required flow rate - fuel pressure drop is baaaad makes car lean, but with a 35 shot you SHOULD be ok)

Id say go for it, check your AFR's (as nitrous WILL cause cooler denser air and also increase your boost) so yeah. Keep an eye on AFR's,, EGT (if you have it) fuel pressure and you should be good to go.

I agree though, dropping your boost for a few test runs would be a good idea. Also see if you can get some diff jets on the car to dial in a little richer mixture on the gas, and watch your knock too - you may want to look at retarding your timing (althoguh again this shouldnt be necessary)
Reply
Old Mar 31, 2006 | 03:05 PM
  #3  
Robertio's Avatar
Full Member
Tenured Member 15 Years
 
Joined: Jan 2003
Posts: 158
Likes: 0
From: Scotland
I had nitrous on mine for a while, on a 25 shot I could feel no difference inside the car, with a 50 shot there was a noticeable gain. You want to run a lot richer than 11:1 with gas on, IIRC I was running 9-9.5:1. We have had to play around with jets to get them matching - had a Skyline well in the 8:1 ratio on an out the box 100 fuel/gas pairing. My car was running around 360rwhp before gas, and it has been shown on the dyno that a 50 shot is worth almost 50rwhp on an FD, though once you get around the 400rwhp mark flow becomes an issue so gains reduce.

I had nitrous on when I blew my last engine, but the failure itself was down to a fuel supply problem. The odds on it failing simply come down to how well the system is installed - if it's fitted properly and everything is setup then you should be fine (but at the end of the day it is your engine and your call).

Obviously I don't know how your setup is configured, however, general practice is after the run (ie on the return road): leave the switch on, close the bottle and do a couple of 2-3 second WOT pulls before flicking the switch off. This lets you clear the nitrous out of the system, otherwise you could find the first time the TPS switch is triggered after the run it will pick up unused gas and run lean (pop goes the engine).
Reply
Old Mar 31, 2006 | 05:29 PM
  #4  
matty's Avatar
Lives on the Forum
Tenured Member: 25 Years
Liked
Loved
 
Joined: Mar 2001
Posts: 5,014
Likes: 40
From: CT
i never understood the point of runnning less boost so u can run shot. why just just throw the shot away and up the boost?
Reply
Old Mar 31, 2006 | 05:34 PM
  #5  
G's 3rd Gen's Avatar
Eats, Sleeps, Dreams Rotary
Tenured Member: 20 Years
iTrader: (11)
 
Joined: Sep 2003
Posts: 3,067
Likes: 7
From: Home of the Rolex 24
Originally Posted by matty
i never understood the point of runnning less boost so u can run shot. why just just throw the shot away and up the boost?
Reply
Old Mar 31, 2006 | 05:38 PM
  #6  
LUPE's Avatar
Banned. I got OWNED!!!
 
Joined: Apr 2005
Posts: 5,506
Likes: 0
From: Belleville, IL
I wouldn't bother spraying until I limit my turbo.
Reply
Old Mar 31, 2006 | 06:44 PM
  #7  
jpandes's Avatar
Rotary Freak
Tenured Member 15 Years
 
Joined: Mar 2001
Posts: 2,236
Likes: 1
From: San Francisco, CA
Let us know how it goes?

Good luck.
Reply
Old Mar 31, 2006 | 09:36 PM
  #8  
fastcarfreak's Avatar
3rd motors a charm I hope
Tenured Member 15 Years
 
Joined: Apr 2003
Posts: 2,054
Likes: 0
From: Central New York
Originally Posted by matty
i never understood the point of runnning less boost so u can run shot. why just just throw the shot away and up the boost?
reason is, as a result of spraying the nitrous, you will get an increase in boost. So somebody who wants to run 12 psi and nitrous will simply turn the boost down a little to like 10 or so, and while spraying, they will have a result of around 12 psi and nitrous.

if they just added the nitrous to a car set up for 12 psi, then you may end up resulting in like 14-15 psi. If your ecu is not tuned that high, then your motor will go bye bye.

Adam
Reply
Old Mar 31, 2006 | 10:42 PM
  #9  
ecarver2's Avatar
local Celebrity
Tenured Member 05 Years
 
Joined: Sep 2005
Posts: 452
Likes: 0
From: South Eastern Mass.
Just buy a bigger turbo.... Y2K baby!
Reply
Old Apr 1, 2006 | 12:36 AM
  #10  
Mr rx-7 tt's Avatar
rotary sensei
Tenured Member: 20 Years
iTrader: (5)
 
Joined: Mar 2001
Posts: 2,316
Likes: 3
From: Virginia
I used to run a 175 shot with a blower. Car was quick but I wouldn't use it again. There is no need on a 3rd gen car.
Reply
Old Apr 1, 2006 | 01:08 AM
  #11  
Robertio's Avatar
Full Member
Tenured Member 15 Years
 
Joined: Jan 2003
Posts: 158
Likes: 0
From: Scotland
Originally Posted by LUPE
I wouldn't bother spraying until I limit my turbo.
When you've hit the limit of the turbo nitrous stops having an effect on outright power, that's why it was taken off my car. It will spool up faster with the gas on, but wont make anymore peak power (unfortunately).
Reply
Old Apr 1, 2006 | 01:31 AM
  #12  
Alcoholic's Avatar
Senior Member
Tenured Member 05 Years
 
Joined: Apr 2005
Posts: 311
Likes: 0
From: Clearwater, florida
Originally Posted by Robertio
When you've hit the limit of the turbo nitrous stops having an effect on outright power, that's why it was taken off my car. It will spool up faster with the gas on, but wont make anymore peak power (unfortunately).
I don't see how you come up with that.

more air + more fuel = more power, obviously. if you reach the limits of your turbo's efficiency, you can still get more oxygen into your combustion chamber by using nitrous and add more fuel to burn with this extra oxygen.

Reply
Old Apr 14, 2006 | 05:11 PM
  #13  
bheiman's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Jul 2005
Posts: 256
Likes: 0
From: omaha
ok

the pills are 16 for n2o and 31 for fuel.

direct port, with 2 nozzles.

is that rich enough? any last objections before i try it.
Reply
Old Apr 14, 2006 | 05:22 PM
  #14  
bheiman's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Jul 2005
Posts: 256
Likes: 0
From: omaha
oh i just called nitrous express and they said its backwards, and it should be 31 for the n20 and 16 fuel. and that would be really rich
Reply
Old Apr 14, 2006 | 05:33 PM
  #15  
Kevin T. Wyum's Avatar
None
Tenured Member 05 Years
 
Joined: Mar 2002
Posts: 1,318
Likes: 1
From: Minneapolis
Wow, some really faulty claims in this thread.

Robertio: Wrong.

Fastcarfreak: That would only happen if your wastegate didn't function properly or was at it's limit, or a manual controller.
Reply
Old Apr 14, 2006 | 05:40 PM
  #16  
LUPE's Avatar
Banned. I got OWNED!!!
 
Joined: Apr 2005
Posts: 5,506
Likes: 0
From: Belleville, IL
Originally Posted by bheiman
oh i just called nitrous express and they said its backwards, and it should be 31 for the n20 and 16 fuel. and that would be really rich
Use this combo


50 shot
35 nitrous jet
24 fuel jet

75 shot
41 nitrous jet
28 fuel jet
Reply
Old Apr 14, 2006 | 05:50 PM
  #17  
SPOautos's Avatar
Hey, where did my $$$ go?
Tenured Member 10 Years
 
Joined: Feb 2001
Posts: 4,413
Likes: 0
From: Bimingham, AL
Surely if the previous owner set all of this up he actually ran it...he might have said he never did but Id guess that was BS to help him sell the car.

Just call the guy and ask him how it did....if it still has the stock engine then obviously it wasnt blowing the engine. I say pull the trigger but do it with a wideband.

Nothing at all wrong with nitrous if its setup and tuned correctly. I'm probably going to throw a 100-150 shot on my rx3. It has a 13b with a large street port, racing carburator, Aeromotive fpr.....I just need a new fuel pump that will flow at higher pressure and Im set.

Make sure everything is in order, works properly, and is tuned properly and you will be fine. Its going to be a lot safer to start out with big fuel pills and work your way down till you get to a good a/f ratio.

BTW - If you notice what Lupe posted...his fuel jets are 70% of his nitrous jets...by that ratio with your 31 nitrous jet you should be running a 21 fuel jet. I would start there. There is no telling what that customer support team was talking about....they probably dont have much rotary tuning knowledge. To them real rich might be 11.8:1 af

Good Luck,
Stephen

Last edited by SPOautos; Apr 14, 2006 at 05:56 PM.
Reply
Old Apr 14, 2006 | 08:45 PM
  #18  
bheiman's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Jul 2005
Posts: 256
Likes: 0
From: omaha
ok, gotcha.
it should be a 35/20 not 16...
im not so sure on nitrous, but...
since i do have 2 nozzles, wouldnt that 2 35 shots? so a 70 shot?
Reply
Old Jul 4, 2006 | 02:31 PM
  #19  
bheiman's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Jul 2005
Posts: 256
Likes: 0
From: omaha
well to bring this back from the dead...

i got everything set up and ready, the only thing i would like to get hooked up is the purge valve (lol)
im going to give it a shot once i finish rebuilding my tranny
anyways

im running 31 N20 and 22 Fuel (X2 nozzles)... its a little rich, but i will be driving around with a wideband on to see where it goes. Where should my afr's be? I am going to start out at 10psi (non sequential) and if im running consistantly really rich, i will go to 11, then 12 psi.

it seems to me i have everything setup right,
any nay-sayers to stop me before i try it hopefully in about a week.
Reply
Old Jul 4, 2006 | 04:39 PM
  #20  
BMike's Avatar
Senior Member
Tenured Member 20 Years
 
Joined: Dec 2002
Posts: 451
Likes: 0
From: Indianapolis, IN
What computer and fuel are you running? NAWZZZ(sic) will increase cylinder pressures and you may want to take a degree or two of timing out to ensure you don't blow the car up or run some higher octane fuel.
Reply
Old Jul 6, 2006 | 05:09 PM
  #21  
bheiman's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Jul 2005
Posts: 256
Likes: 0
From: omaha
im running either 92 or 93 octane...
Reply
Old Jul 6, 2006 | 07:31 PM
  #22  
GoodfellaFD3S's Avatar
Original Gangster/Rotary!
Veteran: Army
Tenured Member: 25 Years
Liked
Loved
iTrader: (213)
 
Joined: Mar 2001
Posts: 30,804
Likes: 646
From: FL-->NJ/NYC again!
Ray Crowe of Malloy Mazda fame runs a 50 shot at 12 psi on his FD.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
_Tones_
Adaptronic Engine Mgmt - AUS
10
May 25, 2021 05:37 AM
Nosferatu
2nd Generation Specific (1986-1992)
7
Sep 5, 2015 02:13 PM




All times are GMT -5. The time now is 09:18 AM.