AFR_ with nitrous

[02Ls1]

Ok guys i want to make shure, to command afr is to divide my Stoich AFR that is 14.62 by 1.195 that will be 12.23? Im looking for this afr because im spraying. If im right i will just put 1.195 On my Eq Ratio vs RPM from 2800 across to 7200 angine speed..

[Cantalope Kid]

You have the math correct. Wet or dry kit would be my first question? You adjust the PE for DRY, and the FUEL solenoid for WET, not the PE.

Also adjust for timing pull -2*/50hp increase for safety. What size shot? You may want to start out with a bit more fuel...say 11.8-12.0 AFR.

Now do you have a wideband to confirm your WOT AFR?

[02Ls1]

Is a wet shot 150, i have the afx wideband.

So if i put the 1.195 On my Eq Ratio vs RPM from 2800 across to 7200 angine speed, it should give me the 12.23 AFR at WOT?

[BlackZJ]

Is a wet shot 150, i have the afx wideband.

So if i put the 1.195 On my Eq Ratio vs RPM from 2800 across to 7200 angine speed, it should give me the 12.23 AFR at WOT?

If you were using a dry system, it would. But you have a wet system so you don't need to set the fueling in the tune.

[02Ls1]

Ok, so i will have to play with it till i get it right then?

[Google]

set PE to 12.6 - 13.2 range tune ve to make afr match your commanded afr, then tune maf to commanded afr.

hook up NOS and jet to recommended jets for power level double check afr should be 11.5 - 11.9 while spraying NOS.

[02Ls1]

Setting my PE to 1.125 will be around 12.6 - 13.20.

The next to steps of ve and maf, how can i do it?

What about if i just lower the fuel jet down to get it to 11.80 - 12.20 range ARF?

[Google]

How new are you to tuning?

[02Ls1]

Im new i been tuning my truck and car, they just have bolts ons and just install a cam on my camaro and the nitrous. So i just want to tune it right with nitrous.

[Google]

Start with VE Tuning. Disable the maf and tune the ve. many good posts on here that tell you how to tune ve. as well a few schools and guides. If you get stuck or don't understand something after doing some reading just ask.

[Google]

Here is a good place to start.

http://www.hptuners.com/forum/showthread.php?t=5058

[Montecarlodrag]

Ok guys i want to make shure, to command afr is to divide my Stoich AFR that is 14.62 by 1.195 that will be 12.23? Im looking for this afr because im spraying. If im right i will just put 1.195 On my Eq Ratio vs RPM from 2800 across to 7200 angine speed..

First tune your engine for N/A. Find the AFR for max power/best track time at wot, and best street drivability at part throttle.
Then tune your nitrous setup with the fuel jets if it's wet. Pull timing depending on shot size.
Read spark plugs after each nitrous run to fine tune your engine, to look for sings of detonation, lean/rich conditions.

With nitrous, the AFR you read with a wideband is only part of the tuning, you also need to read the plugs.

[02Ls1]

So lets say I find my afr for n/a and its at 13.20. Thwn I tune it for nitrous and leaved it at 11.90, If I run all motor my afr would be at 13.20 or no?

[LSxpwrdZ]

If you are running a wet nitrous system then the tune on the computer running your car has little to nothing to do with the nitrous side of the fueling. Get the car running good NA with your tuning on the computer and then spray the car with the correct jetting that is supplied with your kit and fine tune the ignition timing and fueling on the spray with the fuel jetting.

If you tune your car to run 13.20 afr then that is what it's going to run when your not spraying. The extra fuel for the nitrous is added through the fuel jet on the nitrous kit so there is no need in changing the PE/Commanded AFR in the tune because by doing so will make the injectors fire more fuel as well. The only thing you should change in your NA tune to run the bottle is ignition timing, and that's only if you don't have a Lingenfelter LNC-002 or the like to pull timing for you when the nitrous is activated.

[02Ls1]

^^^thanks...

[blacklightning744]

ok so i have a question then, if its not to much, say i wanna run for the moment all motor, wouldnt i notice a decrease in performance cuz its tuned for spray? i wanna run 150 wet shot of nitrous, all the fueling makes perfect sense and the timing pulling as well, but if i wanted to run just motor for the moment, would i have to constantly run with 4-6* pulled from the timing tables???? i guess what im asking is, is it a trade off where the motor will run with lower timing on just NA??

thx guys,
Tom

[02Ls1]

Yes if your timing is tuned for nitrous, lets around 20* of timing it will run at 20* of timing N/A to...

[sreve]

Yes if your timing is tuned for nitrous, lets around 20* of timing it will run at 20* of timing N/A to...

You can get around that look at the IAT tables they have there own
timing & PE with a relay and a resistor you can create nitrous only values
that come on when you spray. If you are not comfortable designing it yourself
Frost sells a kit.

[LSxpwrdZ]

You can get around that look at the IAT tables they have there own
timing & PE with a relay and a resistor you can create nitrous only values
that come on when you spray. If you are not comfortable designing it yourself
Frost sells a kit.

I love the idea behind it but on a OL SD car messing with the IAT input will drastically change fueling on the motor tune aspect of it as well. I know there is a tradeoff because it can be tuned around with the fuel jet on the kit, I'm just OCD when I know something is being modified for one thing and it affects something else at the same time.

[Higgs Boson]

You can get around that look at the IAT tables they have there own
timing & PE with a relay and a resistor you can create nitrous only values
that come on when you spray. If you are not comfortable designing it yourself
Frost sells a kit.

not with a wet kit.