How safe is Nitrous on a stock GT?

[MrClean]

Mr CLean I would go with Richards tune any day. He is one of the few in the country I would let tune my car. I would stick with a fogger as well. You will be happier .

Thanks for the feedback, dude; I'll take your advice (on getting Richard to do my tune).

Please excuse my ignorance; the fogger you mention...is that the HSW plate above, or the nozzle thingy that came with the ZEX kit (which is currently installed and working well in any event)?

 

[Bkid]

Thanks for the feedback, dude; I'll take your advice (on getting Richard to do my tune).

Please excuse my ignorance; the fogger you mention...is that the HSW plate above, or the nozzle thingy that came with the ZEX kit (which is currently installed and working well in any event)?

I would ask Richard , and I am pretty sure he will tell you the fogger is the better. The fogger is the part on you Cold air intake, and yes it came with the Zex kit. I think that is the better way to go. If you had a built block then yea that might be a better way to go. I know 2 guys with that same plate system.1 IS looking for a new motor, the other is looking for a better manifold.

 

[MrClean]

I would ask Richard , and I am pretty sure he will tell you the fogger is the better. The fogger is the part on you Cold air intake, and yes it came with the Zex kit. I think that is the better way to go. If you had a built block then yea that might be a better way to go. I know 2 guys with that same plate system.1 IS looking for a new motor, the other is looking for a better manifold.

Good feedback, thanks. I'll just keep what I got now (the fogger that came with the ZEX kit..it ain't broke, I ain't gonna fix it. However, I will get him to write me a specific tune that maximizes torque below 3000 rpm, then from 3000 rpm on up keeps Spark ATDC at 20º, and AFR throught at 12.8.

 

[chopstix]

Well you need to figure on A/F which is very important. I hope you have a wideband A/F guage. STILL you need a good tune, I just would reather be safe than replacing a motor . I am only trying to help .

You are talking about 2 different things.....but your overall thought process is OK

You have an NA tune...(PCM)
Then you have your nitrous "tune"....you adjust nitrous A/F ratio with fuel jetting not PCM parameters.

On my car I use a seperate fuel system to feed the nitrous kit so I can "tune" the nitrous A/F by changing jets for large changes and fuel pressure for small adjustments.

Once you have the motor "tune" complete, the only parameter to adjust in the PCM is the timing.

 

[matt texass]

You are talking about 2 differnet things.....

You have an NA tune...PCM
Then you have your nitrous "tune"....you adjust nitrous A/F ratio with fuel jetting not PCM parameters.

On my car I use aseperate fuel system to feed the nitrous kit so I can "tune" the nitrous A/F by jetting for large changes and fuel pressure for small adjustments.

Once you have the motor "tune" complete the only parameter to adjust in the PCM is the timing.

+111111 don't mess with the AFR through the PCM use the nitrous jetting to do that. Only use the PCM to change the timing.

 

[MrClean]

+111111 don't mess with the AFR through the PCM use the nitrous jetting to do that. Only use the PCM to change the timing.

So does anyone know what the stock tune WOT timing is?

 

[chopstix]

So does anyone know what the stock tune WOT timing is?

27-28* at W.O.T.

 

[chopstix]

On the plate vs nozzle debate...

A plate is typically better than a nozzle as most plates use multiple discharge points. This provides better atomization and helps with distribution. The fuel is atomized by the pressure and vaporization of the nitrous, so the more points you can have fuel/nitrous contact the better.

Now to take it a step further there is not a huge difference in a perimeter discharge and a 360* discharge for most EFI applications. On the S197 intake the TB is located at the front of the manifold, air will pass through the TB/Plate and pull the mixture into the plenum and will then be distributed to each intake runner.

Now a carb intake on the other hand a full 360* discharge is a benefit as the carb is located in the center of the intake. The plenum is directly below the carb and the runners pull from all sides of the plenum.

To produce a 360* discharge requires a multiple piece plate, I would prefer to have a plate that is machined out of a single billet rather than adding another place for them to leak.

 

[SloSVO]

Doesn't steeda or someone make the IMRC plates and are plumbed for oxide?

 

[07 procharger]

yes im running a set. they are steeda

 

[Lazy Racer]

You are talking about 2 different things.....but your overall thought process is OK

You have an NA tune...(PCM)
Then you have your nitrous "tune"....you adjust nitrous A/F ratio with fuel jetting not PCM parameters.

On my car I use a seperate fuel system to feed the nitrous kit so I can "tune" the nitrous A/F by changing jets for large changes and fuel pressure for small adjustments.

Once you have the motor "tune" complete, the only parameter to adjust in the PCM is the timing.

Interesting, so if I am rich on my 100 shot tune, does it matter if I increase the n20 jet a size or decrease the fuel jet a size to lean the mix a bit?

What do you use to adjust fuel pressure? Is that main system fuel pressure or secondary fuel system? secondary I suppose...

 

[08gt4u]

Doesn't steeda or someone make the IMRC plates and are plumbed for oxide?

let me get this clear if you use the steeda that means youll have to go direct port correct

 

[07 procharger]

yep, unless you plug the holes.

 

[08gt4u]

thats what i tought.

 

[MrClean]

Doug at Bama agreed to write me the 100 shot tune...he finally believed me that I would swap out the jets (was running a 125 shot). I decided that I needed to keep this a "safe" practice (sparying), since I just about go through a bottle a week in daily driving....as a side benefit, the tune when on motor isn't as much as a dog as it was with 4º pulled, and the bottle will last me 20% longer!

Also, I just took delivery of my Speed Depot billet aluminum btole bracket. $140 with shipping included...so much more user friendly that the nasty clamps that came with the ZEX kit...and sooooo much better looking! I'll post pics L8R.

 

[07 procharger]

doesint Doug still pull 4 degrees for his 100 shot tune?

 

[MrClean]

We'll see...I'll datalog when I receive the tune and have it loaded. I can then compare it to what I was running, which was his 87 Perf with 4º pulled.

I'll also "know" how it feels from a "seat'o my pants" torque at WOT while on motor perspective.

 

[chopstix]

Interesting, so if I am rich on my 100 shot tune, does it matter if I increase the n20 jet a size or decrease the fuel jet a size to lean the mix a bit?

If your nitrous A/F mixture is rich you would lower the size of the fuel jet. For the avg street nitrous (up to 150hp) user I suggest tuning to 11.8 or so on a wideband.

As a side note, rich is not "safe"...the correct A/F ratio is "safe"

What do you use to adjust fuel pressure? Is that main system fuel pressure or secondary fuel system? secondary I suppose...

I am running an intank 255lph pump with a second inline 255lph pump feeding through an Aeromotive EFI regulator set to 45psi. The nitrous system feeds off of a 1 gal cell that has its own 255lph pump and regulator set currently at 11.5psi.

To adjust nitrous A/F ratio I either change the fuel jet or adjust the flowing fuel pressure of the low pressure fuel system.

 

[chopstix]

Doesn't steeda or someone make the IMRC plates and are plumbed for oxide?

does anyone have any "good" pictures of these...the ones on Steeda's website are not very good.

 

[07 procharger]

ya hold on