Al,

LS1's run 4-bar (58psi). His application runs 43.5psi or 3-bar (see post #6). The tune in a '99-'00 LS1 f-body show's an injector flow rate of 26.4lbs per hour at 0kPa of manifold vacuum (again, this is at 58psi). I can show you a screen shot of EFI Live if you'd like. Dial back the pressure down to 3-bar and that injector is going to flow less. No old wives tale....simple physics.

 

That's slightly confusing due to the fact that the LT1 is using 44psi and the LS1 uses 58psi.

If an injector is rated at 26 lb/hr using 58psi, then when you drop it to 44 psi, it'll run at a lower lb/hr.

That's the exact reason why you can use 30# SVO injectors in a heads/cam LS1 and make 470+ rwhp with it. They act like 36# injectors when they are under 58psi, because Ford rates them 30# @ 30ish psi.

Check an EFI Live or LS1 Edit injector table.

Mike

 

Guy s guys guys the injectors are NOT rated for any specific motor. The rating comes from the manufacturer of the injectors without knowing what they are going to be used for.

I'll say it one more time all injector ratings are done at 3 bar.

The car engineer then chooses what style injector at what pressure will support the hp that is needed.

Going by what you guys are saying a set of SVO 30 lb injectors would support 800hp in an LS1 up because they are "rated" 30 lbs at the 30psi that a mustang runs and at 58psi that would double??? My 36 pounders are 36 pounders. Nowhere did it say 36 lbs per hour only if in an LS1.

I know very well that many cars fuel systems use differing fuel pressures TBI, TPI, LT1, LS1 but this has nothing to do with the injector manufacturers factory rating.

 

Here's a small quote from a racing injector page.

High Impedance RC Racing Injectors are available in the below listed sizes, all rated at the industry standard of 3 BAR (43.5 psi).

Get that ''industry standard ''.

And I know perfectly well that if you vary the pressure to an injector that it will vary the output. But that has nothing to do with the rating.

 

I think you have me convinced.

 

So, by your definition and assumption that everyone actually uses the industry standard, LS1's don't run 26 or 28lb injectors. That's essentially what you're saying?

1999 F-body Injector Flow Rate Table as seen in EFI Live


2002 F-body Injector Flow Rate Table as seen in EFI Live


My SVO 30# injectors, rated at 40psi (we think), need an injector flow rate similar to that of a 36~37# injector in order for my tune to run right thanks to the 58psi of the LS1 fuel system. If I were to tune it as if they only flowed 30#/hr, I'd be sh!tt!ng black smoke from being too rich.

You saying the 26#/hr injectors (the original poster mentioned) will flow 4# more fuel in his application is simply incorrect. Industry standards exist and manufacturers probably do try to follow them most of the time. But, that's not what this thread was about. It was about his application and the fact that he's running less psi in his fuel system than the car the injector came from.

 

My 26lb injectors should come in the mail any day now. I will throw them in, and post the results.

 

SSpdDmon,

You want to bring up the SVOs all the time but you tell me that the thread is about Examguy putting 26.4# injectors from a GM car into his GM car. What's the fact that Ford racing rates a special injector with 3 psi less pressure got to do with this question.

 

I give up...