Ken in AZ

What do you guys think about this setup? I went kinda rogue on this as I didn't see anyone doing anything similar to my build.

On a GMT800 truck 2002 DBW 5.3

F90000267 pump in tank 450lph
Racetronix Hotwire kit

I heard that combo would max out the return regulator in the stock system so I got this regulator and plumed it to the relief port on the passenger side rail. I drilled the rail fitting to 1/4" which also removes the threads for the schrader valve so it can flow a little more.

Injectors are 80lb e85 compliant and plan on running vacuum regulated with idle psi at 43psi to help with tuning.

03regcab sierra

iTrader: (7)

That looks good! I have ran the corvette filter on a couple of those to make it return style but that's not boost/vacuum referenced


Just FYI the stock return regulator will hold more than you mentioned.
I still have the stock vacuum/boost referenced regulator on my twin turbo truck using 2 Walbro 450 pumps.

Ken in AZ

Thanks for the feedback! I really only read that the stock regulators have trouble holding 58psi and that the pressure can rise or spike depending on the situation with that pump. I also read that it's possible to tune around it as well, but I wanted to run lower pressures for idle performance with such big injectors. I also wanted to increase drivability as well. I'm running a pretty big cam so all the little things help drivability I've heard.

Don't forget it looks kinda cool too

GMCtrk

iTrader: (27)

The stock regulator does not handle the walbro 450, not even close.

Atomic

iTrader: (42)

Looks good! I run 127s at a 55psi base and its just peachy at idle

03regcab sierra

iTrader: (7)

Then how is my truck still running with 2 450s pushing fuel through it?

GMCtrk

iTrader: (27)

It has nothing to do with it running. It will run, that's not in question. It just wont regulate fuel pressure properly.

03regcab sierra

iTrader: (7)

I have logged fuel pressure and it stays steady but it will spike once for a split second when I let off. Not bad enough to where I need to fix it just yet. It will get an aftermarket regulator and rails when I blow up the 4.8 and go with a big cube motor

Ken in AZ

Well this happened - FYI the schrader was driller out, it's much to small to regulate fuel pressure and has to be drilled...but as you can see it is too delicate when drilled.

What's the best aftermarket fuel rail setup?

<a href="http://s35.photobucket.com/user/avg30et/media/535F43A7-46AE-412F-BC78-D81293FC16D2.jpg.html" target="_blank"><img src="http://i35.photobucket.com/albums/d151/avg30et/535F43A7-46AE-412F-BC78-D81293FC16D2.jpg" border="0" alt=" photo 535F43A7-46AE-412F-BC78-D81293FC16D2.jpg"/></a>

Atomic

iTrader: (42)

If you know a guy that can tig just drill out the hole a bit and have a -4an bung welded on.