I ordered an Intellitronic digital fuel pressure gauge with the required sender. The sender is supposed to connect to your fuel rail somewhere. Problem is it is not the same size as the schrader valve. I heard I need an adaptor from "SNAP ON tools" or something. Is there any other way. I know I'm not the only one who has hooked one up. Please help, II'm desperate!
thanks

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'92 Formula
305 TPI
Mods: SLP catback,SLP air foil,ported plenum,Crane AFPR (49psi),MSD6AL,homemade cold air,K&Ns,3:73s,JET fan switch...SLP 1 5/8ths are coming...oh yes

 

Please help me! I have a mustang VS F-body meet in Raceway Park New jersey tomorrow and I have to get this gauge installed.

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'92 Formula
305 TPI
Mods: SLP catback,SLP air foil,ported plenum,Crane AFPR (49psi),MSD6AL,homemade cold air,K&Ns,3:73s,JET fan switch...SLP 1 5/8ths are coming...oh yes

 

The fitting on the rail is a 1/4" male flare. The fitting on your sender is probably a male 1/8" NPT. Your local speed shop should stock some Earl's adapter fittings & stainless braded teflon hoses that will do the trick in some configuration. Get a short stainless braided teflon hose (female 1/4" flare to female 1/4" flare), a male 1/4" flare to male 1/8" NPT adaptor, and a female 1/8" NPT to female 1/8" NPT adaptor (coupler). Ace Hardware should also have the fittings to make the connection.

Tim

 

Tim, I bought a female 1/4" 90 degree elbow to connect to the fuel rail pressure tester and it does not fit. Are you sure it's 1/4" on the 305 TPI from 1992?



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'92 Formula
305 TPI
Mods: SLP catback,SLP air foil,ported plenum,Crane AFPR (49psi),MSD6AL,homemade cold air,K&Ns,3:73s,JET fan switch...SLP 1 5/8ths are coming...oh yes

 

It is a 1/4" male flare fitting. Did you get a 1/4" NPT (pipe thread) fitting? If so, it will be much larger in diameter than a flare fitting. You will need either a short stainless steel braided teflon hose with 1/4" female flare fittings at both ends from a local performance shop (or Summit or Jegs - Earl's makes them), or a 1/4" female flare to 1/4" female flare adaptor from a hardware store - it has two 1/4" flare nuts on each end of a short piece of copper tubing that has been "flared" at both ends. Also, What is the outside diameter of the threaded fitting on the gauge transducer? If it is about 0.395" (approx 3/8"), then it is a male 1/8" NPT fitting.


Tim

 

Ok Tim I got the proper hose and made the connection. I set the FP to 52 hose on 56 hose off. Ok I woke up this morning and my gauge is showing 37 hose on and 37 hose off! It never changed! It just dropped down to 37 from 52 overnight. I connected a conventional analog gauge up and it read 58. Again I disconnected the vaccuum hose with no different results. Is my regulator bad? I just bought it last week?

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'92 Formula
305 TPI
Mods: SLP catback,SLP air foil,ported plenum,Crane AFPR (49psi),MSD6AL,homemade cold air,K&Ns,3:73s,JET fan switch...SLP 1 5/8ths are coming...oh yes

 

You should set your fuel pressure with the engine running & the vacuum hose removed from the fuel pressure regulator. Did you remove the schrader valve from the fitting on the rail? Verifying the reading with a mechanical gauge, like you did, is a good idea - the readings may differ by a few psi. Other things that may affect a pressure reading are using a fuel pressure isolator diaphragm (for running a mechanical gauge in the passenger compartment) - too much air on the secondary side of the diaphragm will cause a low reading, or a liquid filled mechanical gauge - the reading will vary by +/- 5 degrees, depending on the temperature of the liquid in the gauge. Since you have a digital gauge, you are probably not using either of the above devices, correct? Also, a good way to verify the fuel pressure reading, while driving @ part throttle, or @ idle is to have a vacuum gauge on the dash, as well. 2" of HG is approximately 1 psi. For example, if you set your fuel pressure to 54 psig, with the vacuum line removed from the regulator, then after you reconnect the vacuum line to the fuel pressure regulator, the fuel pressure should read 47 psig if the vacuum reading is 14" HG (54 - [14 / 2] = 47).

Tim