Adding more injectors
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Adding more injectors
I'm new to SC tuning and was wondering some things about fuel management specific to injectors for a particular application. I have seen some set ups where adding another injector in the fuel rail or possibly a new fuel rail/manifold for an additional stock injector per cylinder, does this allow you somehow to get around the need for a stand alone ecu? Will this give you the needed extra fuel wile still utilizing the factory fuel management? Is this why this is done versus a bigger cc injector? Thanks for any insight...
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Originally Posted by Enthralled,Jun 4 2008, 09:52 PM
the stock injectors will hold up to 7psi without upgrading anything.
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if you simply add more fuel injectors to the factory ecu with nothing to control them just splice them from the original wires you are going to be running super rich all the time. In otherwords you are going to be getting double the amount of fuel. Not sure how unfamiliar you are about fuel managment. But the only time you need more fuel for forced induction is when you go into boost. If you simply added injectors to your setup you would have extra fuel all the time. Your assumption is wrong. It does not work this way. That is why everyone runs a piggy back or stand alone with larger volume injectors.
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Originally Posted by rob!,Jun 5 2008, 07:09 AM
if you simply add more fuel injectors to the factory ecu with nothing to control them just splice them from the original wires you are going to be running super rich all the time. In otherwords you are going to be getting double the amount of fuel. Not sure how unfamiliar you are about fuel managment. But the only time you need more fuel for forced induction is when you go into boost. If you simply added injectors to your setup you would have extra fuel all the time. Your assumption is wrong. It does not work this way. That is why everyone runs a piggy back or stand alone with larger volume injectors.
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the computer doesnt know if you are NA, supercharged or turbo charged. so it would work with a supercharger. A piggyback i was referring to would be the greddy unit which most people use. VAFC is not the safest way to manage your fuel. Sure people use it, and yes, people blow their engines. I suggest something else though because the s2000 engine is not cheap.
Me personally use a full standalone (aem) because i want it to be as safe as possible. There is many guys getting by on a piggy back though. goodluck. keep researching before you try anything. There is a lot to know to go along with FI
Me personally use a full standalone (aem) because i want it to be as safe as possible. There is many guys getting by on a piggy back though. goodluck. keep researching before you try anything. There is a lot to know to go along with FI
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Originally Posted by rob!,Jun 5 2008, 10:11 AM
the computer doesnt know if you are NA, supercharged or turbo charged. so it would work with a supercharger. A piggyback i was referring to would be the greddy unit which most people use. VAFC is not the safest way to manage your fuel. Sure people use it, and yes, people blow their engines. I suggest something else though because the s2000 engine is not cheap.
Me personally use a full standalone (aem) because i want it to be as safe as possible. There is many guys getting by on a piggy back though. goodluck. keep researching before you try anything. There is a lot to know to go along with FI
Me personally use a full standalone (aem) because i want it to be as safe as possible. There is many guys getting by on a piggy back though. goodluck. keep researching before you try anything. There is a lot to know to go along with FI
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greddy would take over the job... but why should you have to make on the fly corrections? esp while driving? i got my car tuned once and never have to touch it. I have a wideband i never look at really. whether it is 0 degrees or 100 degrees (NJ weather) i dont have to touch anything. It has o2 feedback built in.
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From: Clifton, NJ
Originally Posted by s2000Junky,Jun 5 2008, 01:45 AM
I'm new to SC tuning and was wondering some things about fuel management specific to injectors for a particular application. I have seen some set ups where adding another injector in the fuel rail or possibly a new fuel rail/manifold for an additional stock injector per cylinder, does this allow you somehow to get around the need for a stand alone ecu? Will this give you the needed extra fuel wile still utilizing the factory fuel management? Is this why this is done versus a bigger cc injector? Thanks for any insight...
My tuner and his shop (Scott of Ballistic Motorsports and Giles of Holyroller Dyno both in Bow, NH) used a secondary fuel rail on a comptech kit with a smaller pulley and the greddy emanage ultimate was used for management. You can still simply use larger injectors instead of having two fuel rails, but my tuner was explaining that there are certain benefits to using the two fuel rails with stock injectors as opposed to a single fuel rail with large injectors.
3. ) Why is this better than larger injectors ...
A.)To Idle a larger injector means you have to get the pulse width to a minimum . The problem with that is you will reach a point where the injector is either on or off . You will never get it to go low enough to idle without running rich . So you get poor idle and poor fuel economy and misfire ( Even if you run a standalone ) . The secondary system can be use with Greddy or even the AEM standalone and have its benefits . ( I did send some parts to some members highly respected in the FI community of this site and they will be using it with the AEM, and one reason is because of the poor ability to idle large injectors . While you might not see the difference between the rail and 550cc injectors you will when you step up to 750cc plus .
B. ) When saying it is a E-manage only problem , that is not true . It is a Problem with any standalone also . The difference is with the Greddy the Factory ECU tells you you are misfiring , while the AEM will not and people learn to live with it . ( My Miata misfires and the motor is bone stock, but it is pre OBDII and it does not care ) Why you ask , well AEM does not worry about OBDII as it was designed for race use only, and the cars dont sit at idle long . But did you know even the AEM drag cars run secondary injection ??? Ahhhhh lots of race cars do smile.gif Even in F1 wink.gif
A.)To Idle a larger injector means you have to get the pulse width to a minimum . The problem with that is you will reach a point where the injector is either on or off . You will never get it to go low enough to idle without running rich . So you get poor idle and poor fuel economy and misfire ( Even if you run a standalone ) . The secondary system can be use with Greddy or even the AEM standalone and have its benefits . ( I did send some parts to some members highly respected in the FI community of this site and they will be using it with the AEM, and one reason is because of the poor ability to idle large injectors . While you might not see the difference between the rail and 550cc injectors you will when you step up to 750cc plus .
B. ) When saying it is a E-manage only problem , that is not true . It is a Problem with any standalone also . The difference is with the Greddy the Factory ECU tells you you are misfiring , while the AEM will not and people learn to live with it . ( My Miata misfires and the motor is bone stock, but it is pre OBDII and it does not care ) Why you ask , well AEM does not worry about OBDII as it was designed for race use only, and the cars dont sit at idle long . But did you know even the AEM drag cars run secondary injection ??? Ahhhhh lots of race cars do smile.gif Even in F1 wink.gif
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