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Had some good weather this weekend and got a little done... On both of my fun cars.
I took the fuel rail off to drill and tap for a fuel pressure gauge. I then cleaned it up and put it back on with some ID1300's, AEM FPR, and an Aeromotive fuel pressure gauge. Other than that, the manifold is at ATP right now getting an Inconel heat shield made and waiting on a new intercooler and bracket from SoS.
Back in the Fall I blew the fuel hose off my Walbro 450 on my STi which led me to do a quick repair on the side of the road with what was left of the hose. I was able to drive it home, but didn't want to touch the car until today. It was fun to get that back out as the mountain roads to my house are a friggen blast!
man ive never got the whole fuel pressure gauge. would that be to check when the car is idling? Arent there digital senders you can wire so you can check inside the cab?
Does the pressure remain the same from idle all way to red line
The gauge is really just to set the base pressure since the FPR is adjustable and isn't set to 3-bar out of the package. I may replace with a sender to run into the ECU at some point, but $35 vs $150 and I don't absolutely need to have it wired into the ECU.
Base pressure is set with no vacuum or boost. I just jumped the pump to run by itself and set base pressure. After that, it's a 1:1 ratio. 10 PSI of boost on the reference port will increase fuel pressure by 10 PSI; -10 PSI on the manifold will decrease fuel pressure by 10 PSI. This is all just to keep the relative pressure differential between both side of the injector the same.
EDIT: Very fitting here... When the fuel line split and slipped off the Walbro on my STi, I was able to determine fueling was the issue quickly as when I popped the hood, the pressure was way down and bouncy... All by the gauge mounted on the regulator.
man ive never got the whole fuel pressure gauge. would that be to check when the car is idling? Arent there digital senders you can wire so you can check inside the cab?
Does the pressure remain the same from idle all way to red line
There are other uses as well as checking to see if the fuel pump can supply enough fuel or has problems. If pressure can't hold steady and drops or is erratic when on the gas it's very helpful to pinpoint the problem (either the fpr or pump). You really can't have enough gauges imo, assuming you actually know what you're doing.
02-19-2017, 05:44 PM
