Hey guys, I would like to know which type of injectors our car uses:

1. Peak & Hold Fuel Injectors
2. Saturated Fuel Injectors

Also are #1 = high impedance injectors and #2 = low impedance injectors ???

Hope you help me. I'm looking to RC fuel injectors, especially 60's.

 

I don't know about peak and hold or staturated for the injector type, but I do believe the Cobalt uses high impedence injectors.

 

Nice post I've been wanting to ask this but keep forgetting lol, gj.

 

Stock are 12 Ohm high impedance injectors.

Here is some possible replacement ones; I suggest to buy them Flow Macthed FM) (and you must change the connectors) :

42# http://www.racetronix.com/621031.html

50# http://www.racetronix.com/17113738FM.html

57# http://www.racetronix.com/3172FM.html

63# http://www.racetronix.com/L107FM.html

Don't forget to calculate your injectors needs at the differential pressure they will flow. This is the fuel rail pressure (55-60 PSI) minus the pressure in your intake manifold (after the supercharger). As an example, the differential pressure with your 2,99" pulley could be (58-15=43) whch is in fact exactly the standard rated injectors pressure of 43,5 PSI.

 

How much power would 50lb injectors support?

 

It depends of how much PSI you will boost in the manifold and some few other factors ... probably around 300whp (Dynojet) with the M62 and a small pulley or more if you run a ported haed and upgraded cams.

 

Very nice info!!, Thanks man +rep

Is this ok?

 

Not totally. How much power to wheel you want to have ? How many Max PSI you'll boost in the manifold ?

 

I think in the manifold is getting to 15 sometimes 16. To the wheel about 250WHP.

 

The fuel pressure at fuel rail into that particular formula should be the differential pressure passing through the injectors, so it's 58-15=43 PSI. So you need some 50# injectors to be safe enough. You should tune them with HPTuners. You also need a one step colder spark plugs it will help you removing a couple of degrees of knock retard.

But better than all of that together could be to try a ported head and upgraded cams and keep the 42# injectors to see ...

 

JMC,

Will i need an adapter harness for those racetronix 50lb injectors?

 

Yep ! Bosch style EV1 connector.

http://www.fiveomotorsport.com/Injector_CONNECT.asp

 

I wrote this Fuel System FAQ a while ago

http://www.ecotecforum.com/forums/showthread.php?t=2743