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What size injectors do I need?

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Old Jan 18, 2011 | 11:45 PM
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Default What size injectors do I need?

I am fixin to put a ms3 in my stock ls1 with a 85mm intake and t/b setup. What size injectors do I need?
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Old Jan 19, 2011 | 08:14 AM
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????

https://ls1tech.com/forums/fueling-i...ump-chart.html
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Old Jan 19, 2011 | 08:41 AM
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Injector size is based on HP.

Once you post your predicted HP, fuel pressure & induction type (N/A, forced induction, or nitrous) then the proper injector can be determined.
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Old Jan 19, 2011 | 01:30 PM
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based on experience & findings from people doing modifications, etc. MY OPINION is if you are sticking NATURALLY ASPIRATED; a set of 37# @ 43.5psi injectors work great and give you some breathing room and are perfectly OK on a stock car, change the IFR and you are USUALLY good to go.

As for the saying with HP, that is how its estimated. www.rceng.com go to technical / sizing page link on the left menu.


FORCED INDUCTION; Usually people start off with 42# @43.5psi injectors and step up if they need to

FYI, LS1 Fuel pressures (STOCK) are 58psi, so an injector rated at 43.5psi @ 37#; is actually a 42# injector at our fuel pressure. confused yet?

That 42# at 43.5psi being used at 58psi (LS1 cars) is actually a 48# injector

ALSO, when you go Forced induction you are pressurizing the ENTIRE intake, hence, there is pressure there, and that is why people get Fuel Pressure Regulators and attach them to the Manifold pressure.
Say you have 42# injectors rated at 60psi, say you are running 10LBs of boost.
Well, at that boost level, your injectors are effectively 50psi rating. So you better be damn sure you have enough injector at the rating where your equivalent fuel pressure is due to boost.
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Old Jan 19, 2011 | 04:04 PM
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Thanks everyone and I am pushing around 400rwh if that helps
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Old Jan 20, 2011 | 07:06 AM
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37# at 43.5psi will be fine for you or somewhere near that value
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Old Jan 20, 2011 | 06:16 PM
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Originally Posted by revinkevin71
Thanks everyone and I am pushing around 400rwh if that helps
based on your numbers.you need a 42lb inj @58psi.you have some options you can re size your factory inj.or buy new ones here's the links.

http://www.corvetteinjectors.com/sho...p?productid=37

http://fuelinjectorconnection.com/sh...iewDoc&docId=6
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