bare minimum need to start hemi 5.7 out of car?

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snapetwo

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I am waiting to get the the auto hotwire kit, computer and wire harness for the hemi 5.7.
Question is, what else will i need after i get this, to make the engine run. I wanna test it out of the car first.
I have a water pump on the engine (don't plan on running it long, just enough to make sure it fires).
What about fuel?
I know im gonna need to get a starter for it to.
not gonna hook the tranny up yet.

so just wire harness, computer, will a 5 gallon gas can and a pump work?, starter and battery?
 
It's efi so your going to need a way to get fuel pressure to 48psi. Prolly need a fuel cell with a high pressure fuel pump along with a regulator set to 48psi.

It's not like an old carb motor where 12-15psi to the carb will work.

Riddler
 
This will work for the fuel system and will be the cheapest:
Walbro GSL392 pump
Wix 33737 corvette filter/regulator

Did you ever get the motor to turn by hand?
 
It did turn by hand, i think it was just a little stuck. Ended up pulling the heads, spraying it, and it turns...just wanna get it to test fire. Even if if runs like crap for a few seconds, just so i know its not dead before I drop alotta cash in it.
 
Fuel pressure needs to be 58psi, NOT 48psi, o2 sesors, and what has already been mentioned.
 
5.7 hemi said:
Fuel pressure needs to be 58psi, NOT 48psi, o2 sesors, and what has already been mentioned.
Click to expand...

It will run without 02 sensors just in closed loop. crank/cam signals, fuel injectors, coils, throttle is about all you truly need plugged in to make it fire. A stock truck pump stuck in a 5 gallon pale running a line to the fuel rail will work. The stock pumps have a built in fuel pressure regulator on the top (fuel outlet). So head to a salvage yard, drop a tank, grab the line and pump and head home.

FYI I think the pump from a 4.7 or even 318 should provide the right pressure range. If I remember right. I had compared my service manuals and my durango pump (4.7) is rated to provide the pressure I need for my 03 hemi.
 
Riddler, I'm sure it was a typo, dont sweat it.
Kevin, closed loop is with o2 sensor's, open loop is like when it's first started and running rich if memory serves correct.
 
kb67mopar said:
It will run without 02 sensors just in closed loop. crank/cam signals, fuel injectors, coils, throttle is about all you truly need plugged in to make it fire. A stock truck pump stuck in a 5 gallon pale running a line to the fuel rail will work. The stock pumps have a built in fuel pressure regulator on the top (fuel outlet). So head to a salvage yard, drop a tank, grab the line and pump and head home.

FYI I think the pump from a 4.7 or even 318 should provide the right pressure range. If I remember right. I had compared my service manuals and my durango pump (4.7) is rated to provide the pressure I need for my 03 hemi.
Click to expand...

This is what I did for testing. If you can, also get the pigtail that plugs into the pump for easier wiring.

If the engine has been sitting for a while pull the fuel rail and injectors apart and clean the fuel rail. When I first tried to fire mine the fuel rail had corroded some and debris instantly plugged the injectors so it wouldn't fire.
 
so will any dodge 318-360mag efi fuel pump work?
 
You need 58psi, so if they have it then yes.
 
I think they put out slightly less than 58. I was intrigued to find out with my service manual that the 03 hemi had a lower psi requirement then subsequent years though I do not have my book here at work so I can't truly answer.
 
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