Nitrous tuning...

[ozorowsky]

What will be needed when I add nitrous to my car? Just retard timing a little?

[Hooper]

Depends how big of a shot you're using. If it's just a small shot you can get away with no tuning.

[jimmyblue]

From what I gather, on a dry shot you just want to look
at the maximum CylAir you see when not spraying, and
peel off a little timing at values above that level to keep
out of detonation. A wet shot however enters the
manifold after the MAF and IAT sensor so does not properly
index the CylAir by either MAF or SD measurements.
If you are running stock timing you probably have plenty
of margin but if you've already tuned it up to the ping
limit without N2O then you have to detune the "upside"
region of the spark table most likely, and better to start
from too little advance then too much....

If you want to force some enrichment as well you may
want to jack the IAT sensor to read -40F using a resistor
and relay off the gas solenoid voltage, and use the PE
Add vs IAT table -40 column as an "afterburner" special
case. If you did this then you also would have the spark
IAT adder in play, to edit.

[MNR-0]

From what I gather, on a dry shot you just want to look
at the maximum CylAir you see when not spraying, and
peel off a little timing at values above that level to keep
out of detonation. A wet shot however enters the
manifold after the MAF and IAT sensor so does not properly
index the CylAir by either MAF or SD measurements.
If you are running stock timing you probably have plenty
of margin but if you've already tuned it up to the ping
limit without N2O then you have to detune the "upside"
region of the spark table most likely, and better to start
from too little advance then too much....

If you want to force some enrichment as well you may
want to jack the IAT sensor to read -40F using a resistor
and relay off the gas solenoid voltage, and use the PE
Add vs IAT table -40 column as an "afterburner" special
case. If you did this then you also would have the spark
IAT adder in play, to edit.

I love this sideways thinking. Always more than one way to skin a cat without comprimising the day to day power.

[Bill@HPTuners]

also keep an eye on what your a/f is on both shots...aim between 11:1-12:1 depending on how big a shot your running.

[ozorowsky]

planning on 150 wet

[Hooper]

I have to tune my car's a/f as my ltfts and stfts are a bit lean. I'm going with a 100 wet shot soon but I need to richen things up before I even think about spraying. You're right, foff667, about the a/f ratio.

[Synergy]

Its not about being Rich, its about having the right mixture. You dont have to be butt ass rich to run nitrous. If its wet, then its much easier. I run full timing on our heads and cam cars with 150+ shots. Just alittle octane in the tank anyways, and your good. I adjust the fuel jet to meet my power needs when on the dyno. This helps out all the power problems. I found that with the supplied values for the jets, they are too rich and dont make the power they should, fix the jets and bang, instant HP and TQ. hope this helps.

Rick

[Hooper]

Its not about being Rich, its about having the right mixture. You dont have to be butt ass rich to run nitrous. If its wet, then its much easier. I run full timing on our heads and cam cars with 150+ shots. Just alittle octane in the tank anyways, and your good. I adjust the fuel jet to meet my power needs when on the dyno. This helps out all the power problems. I found that with the supplied values for the jets, they are too rich and dont make the power they should, fix the jets and bang, instant HP and TQ. hope this helps.

Rick

You're right, you don't need to be "butt ass" rich, as you say, but you want to be toward the richer side. Not too rich, because you'll lose power.

When you say "a little octane in the tank", do you mean 94 or actual octane booster? Oh, and what kit were you referring to regarding the miscalibrated jets? Thanks.

[Synergy]

I am using NX equipment. I find that with any wet setup, it has to be customized. I just added one to two gallons of race gas to be safe. So I think with our 91 and the 110 I added, yeah, about 94-95 octane.

rick

[SicBastard]

Brilliant!!!:

"From what I gather, on a dry shot you just want to look
at the maximum CylAir you see when not spraying, and
peel off a little timing at values above that level to keep
out of detonation. A wet shot however enters the
manifold after the MAF and IAT sensor so does not properly
index the CylAir by either MAF or SD measurements. "

[MMGT1]

Hold on a sec here. I thought you would NEVER let NOS come in contact with your MAF. Wouldn't it screw it up first shot?? Again, I thought if going with a dry set up, that the NOS was to be entered into the system between the MAF and the throtlebody....

[stevebo17]

When I ran a dry shot mine came in throuh the bottom of the throttle body. I actually had a hole that the nozzle came though

[gold98Z28]

i have always and will always run a wet setup but, there are many "factory" kits out there that place the N2O enters befor the maf and not sure what long term effects that me be but def not a instant failer since many companies(nitrous) say to do so.

[MMGT1]

Wow, I didn't know that one. I placed mine between the MAF and the throttle body but I would have liked to have placed it further back for better atomization....I need to look into this. Thanks for the info!!

Paul

[gold98Z28]

there is a halow kit i believe its called that places a tube in the airbox and fogs the entire airstream and can easily be a hidden setup. it was much harder to hide my wet setup but i think ive done a great job of it.lol

[MMGT1]

Mine is tucked away quite nicely as well On the dyno two nights ago and got my AFR set to 11.6:1 while spraying(Actual) Commanding 11.0:1. Any richer and I made no additional power. Took only 2* off timing and showed no KR. This is a 75 dry shot in a 3400 Grand Am

[Nithros]

I thought on a dry shot it must spray through the MAF so the PCM can at least see more/colder air is coming in know that more fuel is needed immediately (maybe not exactly how much - just more). Also, you definitely want it before the MAF if you going to be using the IAT table to retard timing.

[gold98Z28]

I thought on a dry shot it must spray through the MAF so the PCM can at least see more/colder air is coming in know that more fuel is needed immediately (maybe not exactly how much - just more). Also, you definitely want it before the MAF if you going to be using the IAT table to retard timing.

very true on a non tuned car, dry shot setups are dependant on the car adding extra fuel. its a guess at best but that is how they calibrate the hp jetting for a xcar specific kit. if you are doing a custom tune for it then........i always use a wet kit as to not have to worry about the pcm/carb what ever it is adding more fuel

[stevebo17]

there is a halow kit i believe its called that places a tube in the airbox and fogs the entire airstream and can easily be a hidden setup. it was much harder to hide my wet setup but i think ive done a great job of it.lol

when I did mine I just ran the line pretty straight forward and put black rubber hose around them. GM's tech actually worked on my motor under warrenty, and never noticed it...