AS title say, im looking into converting my stock fuel rails into a complete fuel return style to use with a walbro 255 and 1000cc injectors. does anyone know how efficient or the max power i can get out of the stock rails converted into a FRS. thanks in advance yes i searched lol and yes i do know that the aam or the cjm rails flow quote unquote 350% more fuel. im really just shooting for 500whp on a DYNODYNAMICS.

 

I made 550whp on dd and then retuned on a dj made 712 whp with stock rails and 880cc injectors. I am running the aam basic fuel return and a custom feed line which consists of a -6 an line from the oem tank (which has a walbro 255 in it) to a bosch 044 inline pump to the rails. Hope that helps.

 

I'm running 550 rwhp & tq with a stanard aps return system (from the kit) and 800cc injectors. I still have plenty of room to spare. This is with stock rails and lines, the rturn is on the fuel tank.

 

The stock fuel rails can easily support your goals when converted to a return system. The stock fuel supply line has less area than the openings to both fuel rails combined. With that in mind, your stock supply line will be a restriction before the stock fuel rails.

 

I used the OEM rails, and it worked out well:












If you plan on welding the -an fittings to the ends, make sure the person is very good with the tig welder. The rails have a zinc coating on them, and that will have to be gound down for a proper weld.

 

very interesting, there are a hand full of people here just running the basic fuel return and making over 600whp.

 

thanks for the response guys. inow all i have to is buy the fitting/fuel regulator/etc

 

this is good information, thanks for sharing everybody!

 

your restriction is the supply line. It's 5/16" which is tiny.

Jtgli is also running twin pumps so you can't use that if you are using a single walbro.


My single walbro on a full return system with stock rails was up to 451hp on a DD dyno. After that the walbro couldn't keep up. I had 800cc injectors and was far from maxing it. You won't need close to 1000cc injectors for 500hp.

If you upgrade your supply line and run a second pump you can get more. The problem will be the single walbro.

 

okay, i might have a new for sale thread then lol

 

the stock rails are probably larger inside than ours or AAMs. the issue with stock rails is the pipes feeding them. the reason people get billet rails is because you dont have to weld proper fittings on them. some people want to just weld fittings on... that works too. but any VQ rail, including stock, that i have seen, is more than large enough on the inside.

 

im making 450whp on 10 psi on a mustang dyno with 440 cc injectors and meth injection. add 10% for dj readings is 495 so between 450-495 is running safe on my block, with no return and im not maxxing out my injectors. because people get all bent out of shape about fabricating dyno #'s to stay on the unbias side. 10 psi - stock fuel system.

 

Whats the Max Fuel Pressure that your running?

 

and you said meth, meth is 20% of the fuel so you take out 20% of fuel usage if you are injecting meth.

That's how people get more use out of a single pump, use meth.

so basically 440's on meth are like 528cc injectors on straight pump.

 

okay what IF i did just stock fuel system (no return), single walbro, 1000cc injectors and hks fcon, ... would by goal of 500 still be obsurd without a FRS???

 

Theoretically you should be okay. A FRS will be much safer though since fuel pressure will be more stable.

 

okay anybody else been down this road before that can comment on my setup (1000cc injectors, single walbro, NO FRS, and hks Fcon)

 

Stock rails will not be any sort of a HP restriction at all!! I have made over 800 RWHP with them and I am sure I could easily crack 1000!

 

is this with or without a FRS???

 

We always do a return system!