Help on injector size
what numbers you think you will be looking at.... obviously above 450hp so **** try sticking in some numbers of what you think on the sticky on the top of this main page. Sorry I'm not much help.
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OK, this is just what I was trying to check too. I have a 383 LS1, mild cam and good heads (~300cfm @.600 intake lift). It should make about 550 hp crank N/A (BSFC @ .5). I will use 53psi as fuel pressure and 85% duty cycle. My calcs say 40 pph injectors.
The next step is turbo @ 6 psi (about 680 crank hp) and 52+6 = 58 psi fuel pressure WOT. My numbers say ~ 50 pph at 85% duty cycle and BSFC at .6.
Looking for opinions, experience, estimates. This should help both of us RedZ!
The next step is turbo @ 6 psi (about 680 crank hp) and 52+6 = 58 psi fuel pressure WOT. My numbers say ~ 50 pph at 85% duty cycle and BSFC at .6.
Looking for opinions, experience, estimates. This should help both of us RedZ!
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From: Frisco TX (Dallas Area)
Originally Posted by white2001s10
Using hillbilly method I come up with 30.99 lb/hr rated at 4-bar.
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1 bar = 1 atmosphere of pressure which is 14.7 psi.
Stock injectors are rated 28 lb/hr at 4 bar 58.8 psi, or round on up to 60psi.
383 cubes - 346 cubes = 37 additional cubes to feed
37 / 346 = 0.1069 (the percent increase in cubes)
0.1069 * 28 lb/hr = 2.9942 additional lb/hr of flow needed
28 lb/hr + 2.9942 lb/hr = 30.99 lb/hr
The proportionally larger injector to match the additional cubes is 30.99 lb/hr.
Most people will move on up to the next larger available size so they can stay in the more "comfortable" zone of 80% max duty cycle.
Considering the stock 28 lb/hr injectors can support an additional 300 lb/ft of torque and 200hp of additional power (a 66% increase) over a stock LS1 engine within the factory rev-range, you realistically do not have to increase injector size in most cases of building a 383 cube engine.
That's why people were asking about your predicted power output with the new engine.
Stock injectors are rated 28 lb/hr at 4 bar 58.8 psi, or round on up to 60psi.
383 cubes - 346 cubes = 37 additional cubes to feed
37 / 346 = 0.1069 (the percent increase in cubes)
0.1069 * 28 lb/hr = 2.9942 additional lb/hr of flow needed
28 lb/hr + 2.9942 lb/hr = 30.99 lb/hr
The proportionally larger injector to match the additional cubes is 30.99 lb/hr.
Most people will move on up to the next larger available size so they can stay in the more "comfortable" zone of 80% max duty cycle.
Considering the stock 28 lb/hr injectors can support an additional 300 lb/ft of torque and 200hp of additional power (a 66% increase) over a stock LS1 engine within the factory rev-range, you realistically do not have to increase injector size in most cases of building a 383 cube engine.
That's why people were asking about your predicted power output with the new engine.
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Verdad Gallardo To take into account your future turbocharger and approx 700hp,
my hillbilly method says that a 65 lb/hr (at 4 bar) is about right for the power level, but you have to either increase injector size and/or fuel pressure when you start dealing with boost pressure in the intake manifold. Many people tack on another 10% or so with boost, which would be about 72 lb/hr.
Obviously the bottom line depends on just how much boost pressure the injectors have to fire into, and how much power the engine will be making.
my hillbilly method says that a 65 lb/hr (at 4 bar) is about right for the power level, but you have to either increase injector size and/or fuel pressure when you start dealing with boost pressure in the intake manifold. Many people tack on another 10% or so with boost, which would be about 72 lb/hr.
Obviously the bottom line depends on just how much boost pressure the injectors have to fire into, and how much power the engine will be making.
Originally Posted by SMOKINV8
I'm not meaning to be an *** here, but do you guys ever look at the sticky within the forums? There's an injector calculator at the top of this very forum.
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Originally Posted by white2001s10
Yep and there's dozens of others out on the net. I think he was just looking for some additional input from people who have done it.