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Did one final leak check last night. Everything appears to be in order. I jumped the pump to the positive terminal to confirm it works and set max fuel pressure. The regulator was already set to 60 psi out of the box so I tightened the nut on top. Here's a sneak peak of how I plan on getting boost reference on the HOBBS switch. If all goes as planned the car should be wrapped up on Saturday then it's the waiting game for the dyno.
Mounted the relay on the hood latch. After trying a few places this worked the best. The wiring itself is pretty simple, the relay has 5 wires. One wire runs to the power on the pump, one runs to a switched source, one runs to the NO pin on the Hobbs switch, and one runs to the battery. The battery wire has an inline fuse for safety.
The Hobbs switch has 3 pins. NC, NO, and C. The NO pin runs to the relay as mentioned earlier. The C pin runs to the ground. The NC pin is not used in our application. When the switch reads a predetermined amount of pressure it completes the circuit which grounds out the switch and in turn the relay. For ground, I ran a wire from the C pin to a bolt on the throttle body. I tapped into another injector for the relay ignition signal and ran the wire under the fuel rail and along the firewall. The power and pump wire are pretty self explanatory.
At this point the mechanical and electrical portion of the fuel system is fully functional. I cut the car on and ran a jumper wire from the NO to the C pin to verify it was operational. At this point everything it twisted together so I pulled it all apart to solder and clean up the install.
I made a make shift wire loom for the relay by twisting the wires together and wrapping them in electrical tape. Made sure to neatly tuck the wires around the firewall and I also opted to replace the wire from the Hobbs to the relay with a black wire so it's less obvious. Last picture is everything neatly tucked away.
Here's a neat video of the Hobbs in action. All that's left is to secure the fuel lines with the supplied mounting clamps. Gonna swap out the wastegate springs and install my wideband next week and have an appointment locked in for a tune on the 24th. So in 2 to 3 weeks we'll have some actual numbers.
2 Days until the car goes back for a final tune. Decided to make a couple modifications to the routing of the fuel lines and also changed the wastegate springs from 7 psi to 12. I moved my T fitting from the e85 sensor to the firewall and made an extra line to attach to it. I also ran the feed line from the FPR underneath the wiring harnesses to make everything less cluttered.
Got the car back this week with not so good news. The car is having fuel pressure issues on the Dyno, and it only gets worse as the car gets hotter. It starts to taper off at 5000 rpms, the powerband drops at 5500 and the car starts to lean out at 6000. Spoke with Shoaf and he believes the auxiliary pump is getting too hot. He suggested I insulate the pump and lines better as they are in close proximity to the exhaust and if that doesn't work it may need a new pump. The good news is the car baselined at 600/600 on the dyno at 4500 rpms on 93 octane despite the car not holding pressure or the tune being dialed in. So at least we know we're headed in the right direction. Gonna set up the Wideband I have and make some adjustments. I also have concerns about the "T" I have in place causing turbulence in the fuel lines at high rpms so I'm gonna replace it with a 6AN "Y" fitting for peace of mind.
Not to get too personal in a build thread but I also lost a very dear friend on the 4th who played a very critical role in this build (she wrapped the car) so revising and finishing are somehow the first and last thing on my priority list. I'll keep you all updated as usual and if anyone has insight on my fuel pressure issue I'm open to suggestions.
Hey guys just a little update. I replaced the T fitting with a Y fitting and also pulled the auxiliary feed from under the fuel rail. When I picked up that line an hour after the car had been shut off the line was scalding hot, a side effect of being right next to the head I'm sure. Something I overlooked in hindsight. I haven't been able to drive the car to see if it performs any differently but I plan on installing my wideband tonight so I can keep an eye on it. Wish me luck.
I have my feeds running behind the heads and they are pretty dang close to the manifolds. I worry about having issues with that. My manifolds are wrapped, but I want to add some more protection in that area.
Hey guys just a little update. I replaced the T fitting with a Y fitting and also pulled the auxiliary feed from under the fuel rail. When I picked up that line an hour after the car had been shut off the line was scalding hot, a side effect of being right next to the head I'm sure. Something I overlooked in hindsight. I haven't been able to drive the car to see if it performs any differently but I plan on installing my wideband tonight so I can keep an eye on it. Wish me luck.
I have had the kit for years and pretty sure I still have highest HP with the kit. Let me know if you have any questions on anything. Maybe I can help out. I don't really get on here that much anymore.
Love the build and love that you love our UPP kit. Keep up the work, love seeing the progress.
Gave you a shout-out on our Facebook page this morning: https://www.facebook.com/UPPCOS/
Hey guys a little update. After rearranging the fuel lines the car appears to drive much better. I haven't had an opportunity yet to bring it back to the tuner but I have a drop off time scheduled with him tonight so fingers crossed it goes well. There are still two track days left of the schedule so I'm hoping to make it to at least one if not both. Will keep you updated.
Hey so I know I've been scarce for updates. Still haven't figured out my fuel pressure issue but it only happens above 6000 rpms so I've got the limiter set at 5500 and I've just been living with it because I'm letting someone use my other car. On the plus side the car did get to stretch it's legs on an HPDE day and it did pretty well until I had to come off the track for non-turbo kit related issues.
05-30-2019, 02:19 PM
