# injector duty cycle **URL:** \ **Category:** SON240sx Automotive\ **Created:** [October 3, 2004, 2:12pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710 "2004-10-03T14:12:40Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![absolum](https://avatars.discourse-cdn.com/v4/letter/a/e47c2d/32.png) [@absolum](https://forums.speedlife.net/u/absolum)\ **Post date:** [October 3, 2004, 2:12pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/1 "2004-10-03T14:12:40Z")
New guy got a question : Is there any way on the sr20det motor to monitor the injector duty cycle . We are trying to up the boost but don’t want to run lean at the same time . Air fuel guage is not the most accurate . Is there any software or management software that will allow to monitor the injector duty cycle, the air fuel or detonation on these motors ? How does it hook up to the car ? ---
**Author:** ![imported\_deeznutz](https://avatars.discourse-cdn.com/v4/letter/i/e79b87/32.png) [@imported\_deeznutz](https://forums.speedlife.net/u/imported_deeznutz)\ **Post date:** [October 3, 2004, 2:58pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/2 "2004-10-03T14:58:52Z")
You’ll need a Fuel computer or and apexi SAFC. Or get and egt gauge, when the temp goes up, your leaning out. Meaning duty cycle is close to the max. -deez ---
**Author:** ![absolum](https://avatars.discourse-cdn.com/v4/letter/a/e47c2d/32.png) [@absolum](https://forums.speedlife.net/u/absolum)\ **Post date:** [October 3, 2004, 3:36pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/3 "2004-10-03T15:36:02Z")
a fuel computer ? can I have more information please . The safc does not give any reading on the car . As far as I know it’s a piggy back system that regulate that modify the air read by the ecm . I don’t think the safc will let you know if you are running lean . the EGT is a good idea but I was also told that the temperature will also increase if you are running rich . I was looking for something more accurate . ---
**Author:** ![DTS](https://avatars.discourse-cdn.com/v4/letter/d/8491ac/32.png) [@DTS](https://forums.speedlife.net/u/DTS)\ **Post date:** [October 3, 2004, 4:29pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/4 "2004-10-03T16:29:11Z")
SAFC-2 Wont monitor injector duty cycle a Apexi AVC-R will. ---
**Author:** ![spd-dmn](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/spd-dmn/32/5513_2.png) [@spd-dmn](https://forums.speedlife.net/u/spd-dmn)\ **Post date:** [October 3, 2004, 5:05pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/5 "2004-10-03T17:05:34Z")
If you’re running rich the combustion chamber temps go down… why would the egts go up? [serious question] ---
**Author:** ![iQuAGoD](https://avatars.discourse-cdn.com/v4/letter/i/f05b48/32.png) [@iQuAGoD](https://forums.speedlife.net/u/iQuAGoD)\ **Post date:** [October 3, 2004, 5:30pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/6 "2004-10-03T17:30:31Z")
He is talking about running lean, not rich… If you are running lean or experiencing knock they will both create higher temperature readings on the EGT, making an EGT an important gauge to have especially on a turbo car. ---
**Author:** ![spd-dmn](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/spd-dmn/32/5513_2.png) [@spd-dmn](https://forums.speedlife.net/u/spd-dmn)\ **Post date:** [October 3, 2004, 5:32pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/7 "2004-10-03T17:32:23Z")
“the EGT is a good idea but I was also told that the temperature will also increase if you are running rich .” That’s why I posted what I did. I was basically saying the same thing you are; namely that an EGT guage is not a waste. ---
**Author:** ![iQuAGoD](https://avatars.discourse-cdn.com/v4/letter/i/f05b48/32.png) [@iQuAGoD](https://forums.speedlife.net/u/iQuAGoD)\ **Post date:** [October 3, 2004, 5:45pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/8 "2004-10-03T17:45:14Z")
If you run rich a bit it doesn’t get dangerously hot… If you run as rich as pavel was, well then your exhaust can will start glowing… but thats not what people usually mean by rich 😛 ---
**Author:** ![absolum](https://avatars.discourse-cdn.com/v4/letter/a/e47c2d/32.png) [@absolum](https://forums.speedlife.net/u/absolum)\ **Post date:** [October 3, 2004, 6:11pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/9 "2004-10-03T18:11:01Z")
nice to know . Apexi avcr and a EGT are thing to have to you want to up the boost . I also read somewhere that the safe injector duty cycle is 80 % . can someone confirm that . Sorry for asking all this question but those sr engines don’t come cheap. ---
**Author:** ![Solarian](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/solarian/32/5514_2.png) [@Solarian](https://forums.speedlife.net/u/Solarian)\ **Post date:** [October 3, 2004, 6:56pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/10 "2004-10-03T18:56:36Z")
80% sounds okay, but I wouldn’t want to go over that. If the injectors stay open a lot, they get messed up. ---
**Author:** ![JoShYo](https://avatars.discourse-cdn.com/v4/letter/j/54ee81/32.png) [@JoShYo](https://forums.speedlife.net/u/JoShYo)\ **Post date:** [October 6, 2004, 5:10pm UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/11 "2004-10-06T17:10:43Z")
If youre upping the boost to a point that youre worried about injector duty cycle, you need to get it on a dyno and use a wideband O2 sensor. High exhaust temps are a symptom of lean mixtures, but why not just monitor the acutal A/F ratio as youre doing it. ---
**Author:** ![boMex](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@boMex](https://forums.speedlife.net/u/boMex)\ **Post date:** [October 8, 2004, 10:50am UTC](https://forums.speedlife.net/t/injector-duty-cycle/81710/12 "2004-10-08T10:50:33Z")
Go Wideband or Go home 🙂