Fuel Pressure Regulator Installation

Last updated: March 9, 1998

Date: Tue, 03 Mar 1998 09:31:35 -0800
From: Spencer Hutchings

I got my SX FPR installed this weekend, finally. It turned out to be real easy.

This all started when I had my ECU upgraded to compensate for a lean condition only to find that my stock fuel pressure regulator had taken a dump. Talking with Eric at XS Engineering I discovered that this was a common 3rd gen problem. Apparently the stock FPR is junk, so I upgraded.

Parts used:

	(1) SX Regulator $150 from XS Engineering
	(1) 90 degree 1/4NPT to -6AN elbow - Summit
	(2) Stright -6AN swivel fittings - Summit
	(1) 90 degree elbow -6AN fitting - Summit
	(1) -6AN cap - $6.25 Summit
	(1) Fuel pressure gauge 60psi - $19.95 Summit
	(1) -6AN Fuel pressure gauge port (I used one from Earls) 
	    - $7 Summit
	(1) -6AN Swivel - Summit
	(5 feet) of -6AN hose $25.00 - Summit
	(4) small fuel injection clamps - Pep Boys or other auto 
	    supply store
	No gaskets must be changed, can if you want to I guess.
	1-1/2 x 6 inch peice of flat metal, aluminum (for making 
	    regulator bracket mount)

Special Tools:

	Hack saw with fine tooth blade for cutting the hose
	(1) 1/4NPT tap OSH or other hardware store
	(1) enough balls to use the above tap to permantly alter 
	    your secondary fuel rail. :-)
	(1) -6AN Wrench - Summit
	(1) Torque Wrench, in-lbs
	Various metric wrenches and sockets
	Various standard Allen keys
	Various Screwdrivers
	Various plyers, very long needle nose, clippers, etc.


  1. Remove all the intake plumbing from turbo outlet to the throttle body

  2. Remove the intake sump, ain't that fun.

  3. Remove the oil filler neck, 3x10mm bolts. two on the base and one underneath towards the front.

  4. Remove the coil pack, mark the plugs with white out or tape.

  5. Remove the mess of vacuum lines 3x12mm bolts and 3x10mm bolts will release the metal frame. It is critical that you mark every single connector and hose you pull off. I get a bunch of small square labels and mark them in pairs and wire tie the labels to each end of every connection. The fuel lines are also on this assembly and are a real pain to get disconnected. I twist and pull very carefully on all the vacuum, fuel and water lines I remove.

    Note: If you have not done so already, now is a good time to switch over to silicone vacuum hose and wire tie them all. If I had it to do it again I would pull the entire assembly out to change the vacuum lines. I makes it much easier to do.

  6. Remove the smog thing on the actual intake manifold 3x10mm nuts

  7. Pull the fuel rail, 2x12mm bolts, 1x17mm banjo bolt

  8. Pull the stock regulator off the rail 2xphillip head screws and discard the regulator and hose.

  9. Shove and old foam ear plug or similar obstruction into the rail so you don't get metal shavings in the injectors. Carefully, tap the fuel rail with 1/4NPT tap.

  10. Insert the 1/4NPT to -6AN elbow and tighten. You want it to end up pointing at the drivers side and angled up at about 30 to 45 degrees.

  11. Remount the fuel rail in the car

  12. Mount the SX FPR on the drivers side, on the far side of the brake booster. I used a piece of aluminum to form a bracket and mounted it into an existing hole.

  13. Using the 90 degree and a stright -6AN fittings make a line going from the regulator to the elbow in the fuel rail. I came out of the front of the regulator with the 90 degree and dropped under the brake booster and back up to the rail.

  14. Make a second line going from the bottom of the regulator to the fuel return line. Discard the old fuel return hose. Use a -6AN fitting on the regulator and and just clamp the other end onto the existing return line.

  15. Mount the swivel, the gauge port, the gauge and the cap on the other side of the regulator.

  16. Hook the vacuum line that went to the stock regulator up to the port on the SX FPR. I routed it along the fire wall.

  17. Put everthing else back together and check for leaks. VERY IMPORTANT!!!!!!!!

I hope this helps someone else out. I plan on replacing the engine mounted gauge with a cockpit gauge as soon as the electronic 2-1/16" Autometer Phantom is available.

Date: Tue, 03 Mar 1998 20:17:15 -0600
From: "Kevin T. Wyum"

The stock FPR was good enough for 11.1 @ 125MPH (in the quarter mile). I don't use it anymore but then again I'm shooting for a little more than 11.1. I find it odd that somebody would claim the stock FPR as junk when they never seem to fail. It's a pretty simple part designed to work with stock line size and keeps the fuel pressure at 40PSI differential. Keep in mind if you change the fuel pressure you will have to change your fuel maps across the board, low RPM, light throttle etc. The point is unless you really know what you're doing I wouldn't play with fuel pressure regulators. It's another adjustment to play with and makes mistakes with.

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