03 must be a hit or miss cuz my buddies is a return style on his 03 truck is all stock too.

 

If the stock fuel system is return less, just use the nnbs rails with the intake and it all bolts right up and stock fuel line fits right on

 

Resurrecting this thread because I have the same question:

So, I have a TBSS intake for my '03 2500 Suburban, and was all set to swap it in, knowing that the 2003+ process is much easier.

And I'm looking at my current intake... and it has a return, not returnless fuel line.

Is this normal? Was there some sort of transitional period when GM was switching over?

Many thanks if any of y'all have background knowledge here...

 

03 is a half year for DBW and returnless for the 1/2 tons

some did, some didn't. It ain't no thing. Corvette filter that pig and roll on

or rail swap it

 

With a return system it's a little more work and it can get expensive. The Wix Corvette C5 filter/regulator (33737) is $45. There are a few different ways to plumb the outlet from the filter to the fuel rail. If you just connect the filter directly to the rail the lines get kinked against the firewall. The easiest plug & play solution is using a fuel feed line from the Corvette that connects to the fuel tank part number 25948212 It's $65 new. Then you need the injector flow rate changed in the tune because you no longer have a vacuum referenced fuel regulator... that cost will vary if you don't have HP Tuners or EFI Live.

You can see were I mounted the filter back on the rail, back from the rails inlet. The long fuel line is the Corvette mentioned above. I bought my filter/line from a member here saving some money. I have HP Tuners so the return type system conversion wasn't to painful money wise.

 

Thank you! That's what I'm planning, but your photo makes it ten times clearer. As always, the theory is simple "use a Corvette filter" but actually engineering the application is where it gets messy. Greatly appreciated.

 

I'm gonna do mine like this!!! What throttle body did you go with?

 

Nick Williams 92mm

 

Ok thanks thats the one im pretty sure i'm gonna go with

 

Ok thanks thats the one im pretty sure i'm gonna go with