Hey guys, Just wondering how exactly the duty cycle is calculated? Reason I ask is I was playing with a 2.6L Rodeo today, pretty much stock motor just a mild cam and exhaust and while doing a full power run the injectors went over 100% duty cycle... Reason im confused is as far as I can tell its a stock injection setup with the stock size injectors and I would not have thought the factory use injectors right on their limit?
So im wondering if anything else can effect it? Does changing the number of squirts or injector staging effects this?
Altho the fuel curve on the graph did start to lean out so seems they are indeed too small...
Does anything else effect duty cycle?
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Read the manual to see if your question is answered there before posting. Many users will not reply if the answer is already available in the manual.
If your question is about troubleshooting, configuration, or tuning, you MUST include your processor type (MS-I or MS-II) and code version in your post. If your question is about PCB assembly or modifications, you must also include the main board version number (1.01, 2.2 or 3.0). For tuning/troubleshooting questions, please attached a datalog and your MSQ file to your post.
If you have questions about MS1/Extra or MS2/Extra code configuration or tuning, please post them at www.msextra.com Such questions posted here will be moved to: a temporary MSextra sub-forum, where they will be removed after 7 days
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ReaperCustoms
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Reaper Customs
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Re: Does anything else effect duty cycle?
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Matt Cramer
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Re: Does anything else effect duty cycle?
It's the calculated pulse width divided by the available injection time. Usually, anything over 90% will make the injectors stick open.ReaperCustoms wrote:Hey guys, Just wondering how exactly the duty cycle is calculated? Reason I ask is I was playing with a 2.6L Rodeo today, pretty much stock motor just a mild cam and exhaust and while doing a full power run the injectors went over 100% duty cycle... Reason im confused is as far as I can tell its a stock injection setup with the stock size injectors and I would not have thought the factory use injectors right on their limit?
So im wondering if anything else can effect it? Does changing the number of squirts or injector staging effects this?
Slightly. The more squirts per engine cycle, the more times you have the injector dead time added to the pulse width. 1 / simultaneous and 2 / alternating produce the lowest duty cycles.
A real possibility.Altho the fuel curve on the graph did start to lean out so seems they are indeed too small...
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ReaperCustoms
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Re: Does anything else effect duty cycle?
Turns out the fuel pump was slowly dieing and pressure was progressively dropping until the car would not even start... Fit a new fuel pump and bingo.