When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
What does that get you over a Hobbs besides avoiding a switch failure?
I'm not sure I understand your question.
Boost referencing has to do with maintaining a constant pressure across your injector. Example: If you have 50psi and 23psi boost, the pressure across your injector (differential pressure) is only 27psi. Now you have to have enough injector to overcome that low pressure. If you boost reference it and have it set to 50psi, it stays at 50psi across the injector no matter what. There's no compensation needed in the PCM. You'll need to change the IFR table and offset table in the tune, which I can help with.
Why not boost reference it and put a 97 fuel filter in place of yours?
no reason probably because I don't know the difference of why I should do it or not. What needs to be done? So good news and bad news. Good news is I am done but I have not powered it because of the fuel issues I had before and still having...http://forums.corvetteforum.com/c5-f...der-boost.html
When the car has been running for awhile and while it's hot outside my fuel pressure drops from 50's/60's to teens if I would let it. I thought it was the aem pump and bap so I sent the aem pump back to aem and they tested it they said no issues. At the same time I ran the stock pump and bap and had the same issues fuel drops hard after a few boosted pulls when ran for awhile. I tried it with the stock pump and bap and same issues. I thought it was the bap so when I got my aem pump I installed it and tried it with and without the bap and same thing pressure drops hard after a few hards runs. It wont do this right away but after temps hit 200 and maybe after an hour of driving and a few pulls it starts happening. It won't do it right away.cruisng no issues whatsoever This happens regardless if I have a 1/4 tank half tank 3/4 tank. Tried different gas stations and still same issues. I want to fix this problem before I introduce another system. ? Should I go return style if so what needs to be done and what is causing this issue before I go return and boost reference. I don't think I would need much considering I have the regulator and rails I just wouldn't know how to return it back to the tank. I have a return coming off the regulator back that goes into that t-fitting I showed before that goes into the external pump
edit: After reading my old thread I posted before I remember you saying to ground the hat awhile back I have not done(I forgot after I was installing everything back to stock) I will try that I just assume a thick 10awg from one of the 7mm head bolts off the hat to a self tapping screw into the frame. I honestly think that may be my problem I am going to do the multimeter test you suggested last time to verify everything...With so much going on with the car and me adding more and more I totally spaced that. I will have Troy kick me if that's my proiblem because I think that's it
""With the pump running, test the wires at the pump head at the driver side. Without the Hobbs running and without the car running, you should have maybe a 1/2 volt drop at the hot wire from up front. Next, measure the voltage with the BAP activated.
Next, touch your meter lead to the pump head cover and the other meter lead to the frame. It should read less than a few tenths of a volt. If it reads more, you lost your ground path in the plug. make a 10 gauge ground strap and ground the pump head to shiny metal on the frame to solve that problem. ""
I talked to CK earlier and he explained to me how to make a return style like you guys mentioned. All I need to do is cap off that t fitting from the upp system, install a 97-98 filter. and return from the regulator just get a -6an to 3/8 and connect that in the rear to feed back into the tank. Only problem is I will have to redo the lines or something how do I get both lines into the regualtor now?
No, the stock feed is already going into the regulator where it connects to the rail. The 2 side ports on the regulator are just a pass-though. You could cap one off and "T" it into the rail anywhere and it would still work. We just used it as a connection point because it made for simple clean install. But as long as it's connected to the system somewhere the fuel still has access to relieve the pressure through it back to the tank.
Guess I'm lost if you look at my pic above CK I have the stock feed going into the driver side rear. Then the crossover in front the the feed from your system goes into the regulator then that feed from the regulator goes into the rear passenger. What regulates the stock feed then? Doesnt that need to go into the regualtor? There is nothing regualting the stock feed line going into the rail..
Shant, the way I set mine up is I have the stock and auxillary feeds merge before the rails and that main feed tees into the back of the rails. Then the front of the rails each go to one side of the regulator. Finally, the return line comes off the bottom of the regulator and feeds back into the tank. I have a '97-'98 fuel filter I swapped in place of my original '02 filter regulator so it would not limit the system pressure.
Guess I'm lost if you look at my pic above CK I have the stock feed going into the driver side rear. Then the crossover in front the the feed from your system goes into the regulator then that feed from the regulator goes into the rear passenger. What regulates the stock feed then? Doesnt that need to go into the regualtor? There is nothing regualting the stock feed line going into the rail..
Our regulator regulates it. Forget for a second that there's 2 fuels systems on there. With just your factory system you could put the regulator exactly where it is now (opposite side of the fuel rail, capping one of the sides of the FPR). Once the pressure in the system reaches 58psi (or what ever it's set to) the regulator opens and drains the excess fuel back to the tank.
(still talking about one system)
Or, you could put the regulator inline on the feed line going to the rail, kind of like we did in our setup. So the fuel actually flows through the regulator to the rail, once the pressure causes a backup it will open the return back to the tank.
(still talking about one system)
Or, you could T your fuel lines one to each rail, then T them back together and go to the regulator. Like what patches is describing.
(still talking about one system)
Or, you could mount the regulator back in the back like they did from the factory.
See, what I'm getting at, is there's a million ways to do it. Just as long as the regulator is tapped into the fuel pressure source at some point, it will do what it's supposed to. All it does is release pressure back to the tank. Imagine a balloon animal balloon (before it's twisted into an animal). If you poke a hole in it it will bleed out. Doesn't matter where the hole is right? Same concept.
Now I kind of see what you're thinking, when you add in the 2x fuel systems. But the line going from the reg to the rail is just a line. Fuel can flow both ways through it. So when you're light throttle/cruise the 2nd system isn't on. Excess fuel travels from the rail to the reg, and back to the tank. When you get on it, the 2nd system activates, and now you've got a whole lot of fuel flow all to the rail. Well all this fuel will create pressure, and the FPR is just a hole to leak pressure from, which it's connected to the system and it inevitably will. At this point majority of the engine is still fed by the stock pump, with the majority of the 2nd pump's fuel supply heading out through the regulator. At some point you're going to overrun the stock fuel system (hence why you needed the 2nd system). At this point the factory pump can't keep up, and pressure in that line/rail starts to drop. This then causes the fuel to flow from the regulator (via the 2nd system) to the rail.
Fuel flows both ways through the line, depending on where the excess lies, but it always maintains a constant pressure (or increases with boost ref).
BUT, you have to take out the check valve if you're running it this way. Which is why I asked about it before. We put it in there to completely seal off our system from the factory when the 2nd one isn't in use. This way if the factory reg is still in place, you don't need this one, and they're not fighting each other. Really it was probably overkill putting it in there, but just to eliminate the possibility of any issues we did.
ahhh I get it yeah I was getting confused as to they had to go through the regulator first. See you mentioned balloon animals and drew me a picture my simple mind now understands. So just to reiterate. All I need to do is cap off the t fitting in the rear and get a 97-98 fuel filter which goes into the blue 3/8" connector then I put a 5/16" to -6an for the return and connect that to green 5/16" connector and remove the check valve in the regulator correct? Thanks again guys I know I can be a little empty between the ears
with filter, fitting, cap...it cost me 26 bucks to convert over to return style with this system....not bad at all.
Good new bad news and ****** news...It is now a return system which is the good news. I ordered the parts from above and installed.
Now the bad news I had no intention of running the secondary until I made sure my fuel pressure dropping issues was fixed first. Well I wanted everything installed and ready to go to where all I needed to do was put the fuse in the UPP kit and it was ready. I did all the electrical and while I was installing the walbro pump the terminal/prong snapped off the positive side there is no fixing it.. so I have to order a new one. No biggie but still sucks,,,
The ****** part..
Fuel pressure still drops hard I mean get into boost and bam falls like a rock. I can go from 59-60psi (that's what I set the base pressure at) and after the car is warmed up and nice and hot Ill get into it and it dropped into the 20's and of course the car has no power. I let off immediately. And when I drove it this am it doesn't do it because the car is cool. What is my issue? I have tried with and without the bap. I have tried return style and non return style. I have tried 2 different pumps. 2 different fuel filters. added a ground from pump hat to chasis and still nada. Won't do it right away just when warm..Things I'm going to do
disconnect hotwire kit and run stock
take fuel cap off and see if i'm causing some weird vacuum issue
log fuel pump voltage
swap injectors...
07-03-2014, 08:09 AM
so I have to order a new one. No biggie but still sucks,,,
