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Fuel pumps and regulators.
https://slantsix.org/forum/viewtopic.php?t=55415		 Page 1 of 2
Author:  Junior [ Wed May 21, 2014 2:59 pm ]
Post subject:  Fuel pumps and regulators.
so after my track time i figured my mechanical pump along with my boost controller arent going to play well together. now im looking at an electric pump and boost referenced regulator. my question is what are you guys running? what have you run? what works well? what should i stay away from? are you running an in tank pump or in line? fuel return or not? if you are running a return how did you route the line back into the tank. at a cursory glance there are alot of different pumps and regulators. just trying to find something that works well.
Author:  Fopar [ Wed May 21, 2014 3:16 pm ]
Post subject: 
To boost reference the mechanical pump requires a nipple installed at the vent side of the pump. look at the pump and you will see where it vents on the bottom side of the pump. you attach a line to it from your pressure going to the intake to that.

Richard
Author:  Junior [ Wed May 21, 2014 3:24 pm ]
Post subject: 
Quote:
To boost reference the mechanical pump requires a nipple installed at the vent side of the pump. look at the pump and you will see where it vents on the bottom side of the pump. you attach a line to it from your pressure going to the intake to that.

Richard
i did that. actually i drilled it out, tapped it and screwed in a compression fitting with brake line attached. it works for the 5psi i was running but doesnt seem to hold up with higher boost levels. also the port from the turbo housing where i was getting the signal was T'd to go to the fuel pump and my wastegate actuator vie the boost controller. the boost controller using a controlled leak was bleeding off pressure so the fuel pump wasnt seeing the same boost as the motor. im just gonna take the pump out of the equation and go electric. aside from what was already said i didnt really like the idea of filling my motor with gas should the diaphragm in the pump fail.
Author:  Fopar [ Wed May 21, 2014 4:15 pm ]
Post subject: 
"the boost controller using a controlled leak was bleeding off pressure so the fuel pump wasnt seeing the same boost as the motor"

There in lies the problem.

Richard
Author:  Junior [ Wed May 21, 2014 5:55 pm ]
Post subject: 
lol i know. thats why im going to go electric to take one problem out of the equation.
Author:  Fopar [ Wed May 21, 2014 7:24 pm ]
Post subject: 
OK but now you are going to add more things to have possable problems with.

Richard
Author:  Shaker223 [ Thu May 22, 2014 10:31 am ]
Post subject: 
Use this pump - Fuel Pump (High-Pressure) - Walbro GSL392

and this regulator......mallory regulator 4309

Both will support up to about 600hp. I have them and have never looked back.
Author:  Junior [ Thu May 22, 2014 10:49 am ]
Post subject: 
Quote:
OK but now you are going to add more things to have possable problems with.

Richard
possibly. but the setup i have now does not work the way i need it to. pumps and regulators are pretty straight forward these days. i doubt the new setup will give me much trouble. now i could be wrong but i like to keep my hopes up.

before i take that setup apart im going to route the actuator to the base of the carb to get the signal the motor is getting and the fuel pump to the turbo housing and see what happens. should get me 8psi instead of 5 on the gauge and take any variables out of the fuel pump circuit. i know these systems have been tested and run up to 15+psi. kinda makes me wonder what the rest of their setup was.
Author:  Junior [ Thu May 22, 2014 10:54 am ]
Post subject: 
the walbro 255lph pump is definitely on the list. its a toss up between the regulator you listed, the mallory 4309 and the Aeromotive 13301. they are both priced about the same and both have good reviews. being the cheap bastard i am its probably gonna come down to which one i can find cheaper.
Author:  Joshie225 [ Thu May 22, 2014 11:27 am ]
Post subject: 
All boost reference lines go to the top of the carburetor!

If you put the wastegate actuator reference on the intake manifold you will build a lot of boost and heat upstream of the carburetor (and plenty of pressure on the turbine inlet) while at mid load and yet have no boost in the manifold. You want the wastegate open when the compressor outlet pressure reaches the desired set point, not the manifold pressure. The best scenario with what you propose is a very responsive engine and the mileage goes to hell.
Author:  Junior [ Thu May 22, 2014 11:49 am ]
Post subject: 
see and that is why i ask most of the time before just doing it. looks like im just going to have to bite the bullet and buy some parts.
Author:  Junior [ Thu May 22, 2014 12:12 pm ]
Post subject: 
i dont get where the problem lies though. my proposed setup would work the same as using my boost controller to get the extra 3psi. it would open the wastegate at 8psi manifold pressure instead of the 8 at the turbo housing and leaving me 5 in the manifold. if i were to set my boost controller to bleed off 3 psi wouldnt it be doing the same thing? im apparently missing something.
Author:  Joshie225 [ Fri May 23, 2014 10:39 am ]
Post subject: 
First off, I don't trust your gauges; mostly because I find it hard to believe you're dropping 3 psi across a 650 cfm carburetor. You shouldn't be dropping 1.5" Hg (about .75 psi).

If you allow the wastegate signal to be determined by manifold pressure the compressor output pressure will go up commensurate with the turbine drive power available. This increases the charge temperature and also drives the turbine inlet pressure up. All this heat comes from burning fuel which does no work in moving the car down the road. For fuel economy people even run the wastegate open under vacuum to reduce exhaust restriction and pumping losses, but that does reduce responsiveness.

Put the wastegate signal at the carburetor inlet or even at the compressor outlet and suffer the small pressure loss across the carburetor and intercooler.
Author:  Junior [ Fri May 23, 2014 10:53 am ]
Post subject: 
Quote:
First off, I don't trust your gauges; mostly because I find it hard to believe you're dropping 3 psi across a 650 cfm carburetor. You shouldn't be dropping 1.5" Hg (about .75 psi).

If you allow the wastegate signal to be determined by manifold pressure the compressor output pressure will go up commensurate with the turbine drive power available. This increases the charge temperature and also drives the turbine inlet pressure up. All this heat comes from burning fuel which does no work in moving the car down the road. For fuel economy people even run the wastegate open under vacuum to reduce exhaust restriction and pumping losses, but that does reduce responsiveness.

Put the wastegate signal at the carburetor inlet or even at the compressor outlet and suffer the small pressure loss across the carburetor and intercooler.
i thought 3psi was alot myself. i think i have another gauge, ill try and dig it up and see what happens.

i understand what you are saying. my question is what is the difference between using the manifold pressure or a boost controller. they both seem to have the same outcome aside from the limited increase when going with the manifold pressure. both are going to make more heat, more boost and keep the wastegate closed longer.
Author:  Junior [ Fri May 23, 2014 10:54 am ]
Post subject: 
im not trying to piss you off. i really do appreciate the help i get here. i just dont understand the difference.
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