naru2 Posted January 16, 2019 Share Posted January 16, 2019 45 minutes ago, Steptoe said: I am hoping someone finds that haul of NOS or someone bought spare by Airtex and never installed I suspect that all the modules were made in one factory and then rebranded and reboxed.I doubt there is any difference Airtex uses the same blurb on all thier modules. It does not seem reasonable that there were 5 different manufacturers of this low volume part like the crossover page suggests. Pretty sure AC Delco never tooled up to make this subaru part. Quote Link to comment Share on other sites More sharing options...
Steptoe Posted January 17, 2019 Author Share Posted January 17, 2019 35 minutes ago, naru2 said: I suspect that all the modules were made in one factory and then rebranded and reboxed.I doubt there is any difference Airtex uses the same blurb on all thier modules. It does not seem reasonable that there were 5 different manufacturers of this low volume part like the crossover page suggests. Pretty sure AC Delco never tooled up to make this subaru part. I suspect you are correct. Possibly all aftermarket stuff built more robust. I ran my turbo for months with knock sensor not even connected as I failed to hook the big black plug together due to stupidity ( still doing it too, found just today I left heater hose clamp way undone, not just mildly - and in our hotest 40°C days!) Propane is my fuel. Better knock resistance. I am on about MKiv of a adaptor block to screw to dizzy base plate in order to mount a module from a standard common old two pin module for next emergency. Even a standard dizzy could get me by but it does not support boost retard And having run my turbo dizzy in non turbo engine it was obvious it's advance curve was not suitable for NA. To run NA curve in turbo might be detrimental Quote Link to comment Share on other sites More sharing options...
Steptoe Posted January 17, 2019 Author Share Posted January 17, 2019 2 hours ago, naru2 said: You don`t need to run your car at boost to check fuel pressure at boost. I use a tire pump and an old subaru check valve to put 7 psi (full boost) on the pressure regulator vacuum line.Fuel pressure should then be 43psi. Volume is important too.For a quick check,I remove the return line and measure the volume. I think a fuel pressure gauge is more important than a boost gauge.I use an onboard oil pressure gauge for fuel pressure I have always felt the same on fuel pressure just not got around to it coz I went propane. Wondered how oil pressure would go long term as we use them for short diagnostic times. Tell me it is not a capillary tube style please !! The more monitoring the better though hard for us pre OBD2 guys. My passenger can see my gas regulator temp, I can only hear the alarm at 3°C before it freezes over. I run a separate 95°C alarm for engine temp and another again to view digital temp and fans on at 92°C I want to do intake air temp,ambient and a time piece but running out of viewable space ! Quote Link to comment Share on other sites More sharing options...
carfreak85 Posted January 18, 2019 Share Posted January 18, 2019 On 1/16/2019 at 3:42 PM, naru2 said: That is 36psi above intake pressue so about 28 at idle.36 not running and 43(36 +7) at full boost. I didn't want to disagree without looking it up first: Straight from the 1984 EA81T FSM Supplement. Fuel pump output pressure - 43.6 psi Fuel pressure regulator regulated pressure - 36.3 psi EA82T, FSM Section 2-7: Pump output wasn't listed, didn't look too long, but willing to bet it's the same as the EA81T Fuel pressure regulator regulated pressure - 36.3 psi Now, I didn't spend any more time looking at whether or not the FPR was rising rate or not, but I don't think it is on either engine. Quote Link to comment Share on other sites More sharing options...
naru2 Posted January 18, 2019 Share Posted January 18, 2019 (edited) On 1/18/2019 at 6:55 AM, carfreak85 said: I didn't want to disagree without looking it up first: Straight from the 1984 EA81T FSM Supplement. Fuel pump output pressure - 43.6 psi Fuel pressure regulator regulated pressure - 36.3 psi EA82T, FSM Section 2-7: Pump output wasn't listed, didn't look too long, but willing to bet it's the same as the EA81T Fuel pressure regulator regulated pressure - 36.3 psi Now, I didn't spend any more time looking at whether or not the FPR was rising rate or not, but I don't think it is on either engine. Are you disagreeing? Like I said,fuel pressure is always 36 psi COMPARED TO THE INTAKE MANIFOLD.(but varies between 26-43 psi on a normal gauge that compares fuel pressure to atmospheric pressure) Fuel pump output pressure is a lot more than 43 psi.It is regulated to 43 max. Deadheaded pressure output is more like 60 or 70.My aftermarket pump is over 100.Pinch your return line and see for yourself.If you only get 43 your pump is dead. You need more than 43 psi available to get a regulated 43 psi output. Read your manual again.You will see that it says "43.6 psi at supercharging 48.0 kPa"(full boost) Of course the FPR is rising rate.It would not need a vacuum line to the intake if it was not. Edited January 19, 2019 by naru2 + atmospheric pressure Quote Link to comment Share on other sites More sharing options...
ausubaru92 Posted January 20, 2019 Share Posted January 20, 2019 Naru is spot on. The fuel pressure regulator is referenced to manifold pressure. Its a 1:1 ratio and thus is not rising rate In my testing with a fuel pressure gauge zip-tied to the windscreen wiper, mid-high 20s at idle, 46psi at full boost (10psi in my case) Quote Link to comment Share on other sites More sharing options...
Steptoe Posted January 20, 2019 Author Share Posted January 20, 2019 Zip tied? I never thought of that! I used 100 mile an hour tape on the glass - over engineered by about 80 mph for that exercise Now, an oops! I bought a heavy arsed Bosch pump for Porsche and Saab turbo 45 psi max to fit to my AX7 First hurdle is the 15 mm inlet instead of required 12 mm. Also looks like I may have under spec'd the pump Quote Link to comment Share on other sites More sharing options...
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