Tuning for wet nitrous question..
Tuning for wet nitrous question.. Ok so what I want is to not loose any or as little as possible hp/tq when running N/A and not using the nitrous. Is there a way to tune so that timing is only pulled when the nitrous is in use? It's a wet kit and I am MAFless tuned in SD.
You basically use a DPST (Bosch style) relay and a switch to change the IAT sensor circuit to switch to a resistor that in placed between the 5v side of the IAT and ground. Since a relay just completes a circuit,you run pin 30 to ground, and pin 87 to the IAT and 87a to a resistor and then the other side of the resistor to the 5v side of the IAT. When then relay is tripped, the PCM "sees" whatever sensor resistance you want, based on the resistor you chose.
The stock tune starts to pull 1 deg of timing at 40c and then it ramps up to 3 deg at 50c. Pick a resistor with the proper resistance; the resistance that the IAT sensor provides at 50c and you will instantly pull timing. Here is the stock IAT sensor resistance chart. If you want to pull more than 3 deg, you will need to modify your IAT Spark Table and pick a resistor accordingly. For mine, I modified my table to pull 6 degrees at 90c and then put a 240ohm resistor in. Then I run the pin 86 on the relay to my NX progressive controller. Works great. If you want to get fancy, you can run a 3 position switch and incorporate two relays... to you can pull timing at two different levels.
This thread has a diagram and a pic of a timing table that shows what I mean.
https://ls1tech.com/forums/nitrous-o...t-how-pic.html
Click here to SEARCH for Resistors
Radio Shack 1/2 Watt Resistors
9420 ohms = 32 *F - 0 *C
7280 ohms = 41 *F - 5 *C
5670 ohms = 50 *F - 10 *C
4450 ohms = 59 *F - 15 *C
3520 ohms = 68 *F - 20 *C
2796 ohms = 77 *F - 25 *C
2238 ohms = 86 *F - 30 *C
1802 ohms = 95 *F - 35 *C
1459 ohms = 104 *F - 40 *C
1188 ohms = 113 *F - 45 *C
973 ohms = 122 *F - 50 *C
667 ohms = 140 *F - 60 *C
467 ohms = 158 *F - 70 *C
332 ohms = 176 *F - 80 *C
241 ohms = 194 *F - 90 *C
177 ohms = 212 *F - 100 *C
132 ohms = 230 *F - 110 *C
100 ohms = 248 *F - 120 *C
77 ohms = 266 *F - 130 *C
60 ohms = 284 *F - 140 *C
47 ohms = 302 *F - 150 *C
The stock tune starts to pull 1 deg of timing at 40c and then it ramps up to 3 deg at 50c. Pick a resistor with the proper resistance; the resistance that the IAT sensor provides at 50c and you will instantly pull timing. Here is the stock IAT sensor resistance chart. If you want to pull more than 3 deg, you will need to modify your IAT Spark Table and pick a resistor accordingly. For mine, I modified my table to pull 6 degrees at 90c and then put a 240ohm resistor in. Then I run the pin 86 on the relay to my NX progressive controller. Works great. If you want to get fancy, you can run a 3 position switch and incorporate two relays... to you can pull timing at two different levels.
This thread has a diagram and a pic of a timing table that shows what I mean.
https://ls1tech.com/forums/nitrous-o...t-how-pic.html
Click here to SEARCH for Resistors
Radio Shack 1/2 Watt Resistors
9420 ohms = 32 *F - 0 *C
7280 ohms = 41 *F - 5 *C
5670 ohms = 50 *F - 10 *C
4450 ohms = 59 *F - 15 *C
3520 ohms = 68 *F - 20 *C
2796 ohms = 77 *F - 25 *C
2238 ohms = 86 *F - 30 *C
1802 ohms = 95 *F - 35 *C
1459 ohms = 104 *F - 40 *C
1188 ohms = 113 *F - 45 *C
973 ohms = 122 *F - 50 *C
667 ohms = 140 *F - 60 *C
467 ohms = 158 *F - 70 *C
332 ohms = 176 *F - 80 *C
241 ohms = 194 *F - 90 *C
177 ohms = 212 *F - 100 *C
132 ohms = 230 *F - 110 *C
100 ohms = 248 *F - 120 *C
77 ohms = 266 *F - 130 *C
60 ohms = 284 *F - 140 *C
47 ohms = 302 *F - 150 *C
Last edited by Goldfinger911; Mar 6, 2010 at 10:47 AM.
