6.0 liter stock fuel injection HP limitations

[347strokin]

Hi guys,

I picked up an 2004 6.0 liter and 4L80E trans for my 87' GMC 2wd.

I'm starting to get a parts list together for the swap but had a question on the limitations of the stock fuel system ands injectors.

My goal is to be between 450-500hp crank HP. Will the stock injectors and fuel system flow this power no problem?

Also is it true these year's 6.0 has a returnless style fuel system? I read that on another forum but haven't confirmed it.

Thanks.

 

[marks86]

injectors on a 6.0 are pretty much maxed out right from the factory. Ford mustang SVO injectors are 30Lbs and are what a lot of guys use. Also 496/8.1 injectors are 30Lbs and 496/8.1 Marine are 42lbs.

I think 30Lb will work for 450-500NA horse power. If you are running a turbo or supercharger you will need more fuel.

Also guys use the corvette filter/regular combo do some research on that.

As for the return less system don't quote me on this but I think they went to a returnless system a few years into the 6.0s being built.

 

[347strokin]

injectors on a 6.0 are pretty much maxed out right from the factory. Ford mustang SVO injectors are 30Lbs and are what a lot of guys use. Also 496/8.1 injectors are 30Lbs and 496/8.1 Marine are 42lbs.

I think 30Lb will work for 450-500NA horse power. If you are running a turbo or supercharger you will need more fuel.

Also guys use the corvette filter/regular combo do some research on that.

As for the return less system don't quote me on this but I think they went to a returnless system a few years into the 6.0s being built.

Excellent info, thanks a lot. Didn't realize the factory injectors were that close to max duty cycle.

I'll look further into the Vette set up.

 

[marks86]

No problem. I actually have one in my garage I'm building as we speak.

 

[347strokin]

No problem. I actually have one in my garage I'm building as we speak.

No way, do you mind sharing your build and expected power numbers?

I've been researching quite a bit but everybody has something different in mind!

 

[Driver4r]

as far as the return/returnless setup, if you want a returnless setup, grab a rail off any 4.8/5.3/6.0/6.2 that's returnless.
The filter can be found on almoast any vette, and a flex fuel s10.

I'm building a meth injected turbo'd 5.3 and I'm going to be around 500ish, its just a trailer puller, so I'm not building it for anything crazy. But I have helped build some LSX TT's in the 1700hp range.

 

[347strokin]

as far as the return/returnless setup, if you want a returnless setup, grab a rail off any 4.8/5.3/6.0/6.2 that's returnless.
The filter can be found on almoast any vette, and a flex fuel s10.

I'm building a meth injected turbo'd 5.3 and I'm going to be around 500ish, its just a trailer puller, so I'm not building it for anything crazy. But I have helped build some LSX TT's in the 1700hp range.

Excellent, thanks!

 

[throttle out]

Was under the impression that all ls motors were return style fuel rails from the factory.
Why would you want to go returnless?

 

[347strokin]

Was under the impression that all ls motors were return style fuel rails from the factory.
Why would you want to go returnless?

I'm not looking to go returnless, just thought I'd read somewhere that some year 6.0's were. But nonetheless, I sold the LQ4 and picked up an LS3.

 

[foamypirate]

Was under the impression that all ls motors were return style fuel rails from the factory.
Why would you want to go returnless?

Nope. 03' up trucks were generally all returnless (I think FlexFuel versions still used a return). My 02' LS1 in my Vette is returnless as well.