Bypassing J-tube
- Thread starter 89MkIII
- Start date
I went from the fuel junction on the block direct to the fuel rail, removing the FPD all together. AN-6 line & fittings; the fuel rail fitting is 14x1.50 mm AN-6...I think the junction fitting is the same, but to be honest, I can't remember. The hose end on the fuel rail is a 120 deg AN-6; the one on the fuel junction hose end is 90 deg AN-6. Here's a couple of pics...sorry the one is a bit blurry, but you get the idea.
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Thanks for the pics. Alright, so if I have this right, everything I need to correctly install a AFPR is basically supplied w/ the LIPP kit I got with the AFPR? Sorry for all the questions, I just want to make sure I have all my ducks in a row when my mechanic friend helps me w/ this install.
You know...you're right. I just re-read the post and I answered the wrong question :icon_conf The FPR is on the return side, the FPD (removed in my pics) is on the feed side where the "J" tube is not even in the loop.
Most guys just drill out the "J" tube or just bypass it completely from the FPR to the fuel return line. It is a restriction w/ an upgraded FPR...and you are correct 7M-GTE, it is there to help the stock FPR with pressure. It should only be removed when upgrading the FPR. I did remove the FPD on my set-up...I have the Walbro pump and don't have any issues with fuel pulse. Pressure is nice and constant.
Most guys just drill out the "J" tube or just bypass it completely from the FPR to the fuel return line. It is a restriction w/ an upgraded FPR...and you are correct 7M-GTE, it is there to help the stock FPR with pressure. It should only be removed when upgrading the FPR. I did remove the FPD on my set-up...I have the Walbro pump and don't have any issues with fuel pulse. Pressure is nice and constant.
Yes, my fuel pump will be upgraded at the same time. So if I'm understanding correctly, the two fuel lines connected to the J-tube (illustrated in my original picture) will be entirely replaced and/or bypassed w/ a braided line in my afpr kit that goes from the AFPR to the fuel return line.
89MkIII said:
Yes...it's the line that screws into the bottom of the FPR (assuming it's an Aeromotive FPR) and joins the fuel return line on the bottom of the car with a nipple/clamp fitting using a short rubber hose piece. You can remove the "J" tube completely and replace it with a plain cover and stock gasket.
