View Full Version : SR20DET Fuel System Upgrade

12-23-2004, 03:57 AM
Fuel Pump

I'm new here so I will make a deposit to the forums search queries, I did a pretty big Fuel System Upgrade Saturday. As seen in the Pic, I installed a Walbro 255LP Fuel Pump, NISMO FPR, and a Fuel pressure Guage.

First things first, with the car running, remove the fuel pump fuse and let the car die out.

Let’s do the Fuel Pump first. This was easier than changing the oil in my opinion. In my specific car, the Fuel pump is easy to get to, it’s in the trunk. Juts lift the cover for the spare tire well and remove the bolts that cover the Fuel Pump carrier/harness. Then disconnect the wire harness that is connected to the Fuel Pump carrier. Yeah it is a bit dirty in there:

Before you can remove the pump you have to take out the (2) fuel lines, don’t lose the clamps, on my car if I wasn’t carefull, they would be gone forever…Be carfull when removing the Pump from the gas tank as not to damage the fuel level Bobber, you gotta turn it this way and that way but eventually it will come out. Also do not let any of that dirt fall in, that would be the sucky..Make sure you cover the hole to the gas tank with a magazine or newpaper so no debris can get in there. Once you have the Fuel Pump carrier out you can ensure the new pump you have is supplied with a power wire and a ground wire..if it is then you can cut the stock wires off, leaving enough to splice in with the new pumps wire harness for power and ground. Here is a pic of them together after, the red and black wires are the ones you cut:


If your new pump does not come with fuel line, buy some..it’s best to use new line. After you cut the old wires, set the new pump in the carrier…When you put the new fuel sack on, there is a little washer that holds the sock on the pump, be carefull with this thing as it is fragile and the only thing that holds the sock on the pump. Then put the rubber grommet over the sock and it is rady for the carrier…After the pump is in the carrier try to get it in as tight asyou can, using the fuel line to move it up and down, this way you can force the pump to stay in the carrier..Some people use zipties to get it tight. I didn’t need to, it fit nice and snug.

Then splice the power and ground wires from the new pump harness to the carriers wires…
Then it should look like this:

After that, just put it back in using the reverse order.
Don’t smoke till your done!

12-23-2004, 03:59 AM
Fuel Pressure Regulator and Gauge:

Not much to write on this, pretty much in and out, but I will cover a few pointers:

This is the old FPR, set to stock settings at 3 Bar:

You will have to take out the Fuel line from the Filter to the Fuel Rail, and the Fuel Line that returns to the Fuel Pump from the old FPR. Again a pointer is to use all new line. These lines are on pretty tight, infact I had to cut the lines that went to the Fuel Rail. Also since I was installing a Fuel Pressure Gauge as well, remember you will need more clamps than you had before, I had to go to the store and buy 2 more.

Once all the lines are off, and all the gas spilled everywhere and you weren’t smoking, you can disconnect the vacuum line on the old FPR and take off the (2) bolts that hold it in. I saved the old one for the heck of it. E B A Y!

For the Fuel Pressure gauge, your fittings may be quite large compared to the Line. In my case they were and I had to run hot water over the line for 10 minutes to get it soft enough to fit over the fittings.. Here is a PIC after I had them on, remember those new clamps? Well here is where I figured out that I didn’t have enough:

Also put some Kevlar tape on the threads of the Guage to make a vacuum seal like this:

Now back to the FPR, pretty easy just use the (2) bolts to re attach in the old placement spot. Then connect the fuel lines back up to the filter, FPR, and Fuel rail. You’re done.
Make sure that if you do not have a good short-term memory, that you take a picture of the old lines to make sure you have them right.

Here is a final PIC

12-23-2004, 06:03 AM
Kevlar tape huh?

12-23-2004, 07:49 AM
Kevlar tape huh?

Be nice, thats a kick ass write up....

Daryl, its Teflon tape and you are SOOO Military! But either way that was a tight write-up. Very well done. You doing a write up for the injectors? I think that would make this wrather complete.

12-23-2004, 01:07 PM
wait what was the teflon tape for?

nice writeup

12-23-2004, 02:37 PM
:duh: Whoops, Kevlar Tape :duh:

Yeah I meant teflon, thats the Marine in me :bigok:

Yeah I am going to add the Injector Writeup..I am running right now at 4 Bar so I think my 370's are pushing 420, or so I have been told. The 550's I will install should be plenty for my plans (S14 T28 15 PSI, Tomei 256 CAMS, and FMIC)..There is an APEXi shop down the road that I did my baseline DYNO add back in October that can give me (2) WIdeband runs for 5000 Yen (PICS on my car domain site), so I figure 10000 Yen should be enough to get my tune on the SAFC, we will see.

12-23-2004, 04:38 PM
LOL. I wasn't trying to be mean. I actually couldn't think of the name cause I was tired.