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Old 10-24-2013, 11:51 AM   #1  
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Default Horsepower vs. Injector size

Does anybody have guide lines for how much horsepower you can expect to get with 19 lbs. injectors? or 24 lbs.? 30 lbs?
I plan on running AFR heads, comp cam, no boost, ported cobra intake. I am not sure what size mass air and throttle size to go for.
best to run same size mass air and throttle plate or should mass air be larger?

I am looking for about 350 rwhp.

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Old 10-25-2013, 01:20 AM   #2  
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There are a number of online calculators that figure these things out for you. They should be pretty easy to find.

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Old 10-25-2013, 07:40 AM   #3  
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You should find a reputable dyno-tuner in your area that will do the custom tune on your car. They will tell you exactly what you need as far as injector size, T/B & MAF size, spark plugs, ect. to reach your power goals.

The first dyno-tuner that I went to had a lot of different recommendations than the guys that I chose to use, Injected Engineering.
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Old 10-25-2013, 11:07 AM   #4  
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+1 ^^
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Old 10-12-2017, 12:14 AM   #5  
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On a ford 5.0l the following will apply...

For 350rwp you will need 40lb inj @ 43 psi. This will leave you head room in the injector duty cycle.

30lb will be maxed out around 330rwp @ 43 psi

24lb injectors will make out at 280rwp @ 43 psi

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