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pulse width / duty cycle

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Old Feb 25, 2007 | 03:34 PM
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Default pulse width / duty cycle

I've searched around and I'm kind of stumped here.

I have a stock 99 camaro SS with the 26lb injectors and I'm considering dry nitrous. I had a 75 shot running on my previous 2001 v6 camaro and was maxing out the injectors, but I don't really want to take any chances on my LS1. I have hptuners and I've been watching my injector pulse width at wot to get an idea of how much nitrous I can run on the stock injectors..
The highest pulse width I've seen was 19msec at 4800rpm.

Can anyone share some figures that show pulse width at 80% duty cycle through the rpm range?

Thanks.
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Old Feb 26, 2007 | 12:10 AM
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i found this table in a document titled ls1tuninginfo.doc that someone put up on the hptuners message board. i wish i knew who to give credit to for this:

Injector Duty Cycle Chart - The general rule is to not exceed 80% duty cycle.

Duty Cycle

RPMs 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
3000 4 ms 8 ms 12 ms 16 ms 20 ms 24 ms 28 ms 32 ms 36 ms 40 ms
3500 3 ms 7 ms 10 ms 14 ms 17 ms 21 ms 24 ms 27 ms 31 ms 34 ms
4000 3 ms 6 ms 9 ms 12 ms 15 ms 18 ms 21 ms 24 ms 27 ms 30 ms
4500 3 ms 5 ms 8 ms 11 ms 13 ms 16 ms 19 ms 21 ms 24 ms 27 ms
5000 2 ms 5 ms 7 ms 10 ms 12 ms 14 ms 17 ms 19 ms 22 ms 24 ms
5500 2 ms 4 ms 7 ms 9 ms 11 ms 13 ms 15 ms 17 ms 20 ms 22 ms
6000 2 ms 4 ms 6 ms 8 ms 10 ms 12 ms 14 ms 16 ms 18 ms 20 ms
6500 2 ms 4 ms 6 ms 7 ms 9 ms 11 ms 13 ms 15 ms 17 ms 18 ms
7000 2 ms 3 ms 5 ms 7 ms 9 ms 10 ms 12 ms 14 ms 15 ms 17 ms
7500 2 ms 3 ms 5 ms 6 ms 8 ms 10 ms 11 ms 13 ms 14 ms 16 ms
8000 2 ms 3 ms 5 ms 6 ms 8 ms 9 ms 11 ms 12 ms 14 ms 15 ms


not sure if this is unique to a particular injector size - 26.6 or 28.x... anyone have any idea?

Last edited by BobDoLe; Feb 26, 2007 at 12:22 AM.
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Old Feb 26, 2007 | 01:13 AM
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something old
Injector Duty Graphs

and something brand spanking new
Injector Sizing Explained
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