The following modification allows the rail to be fed from both ends with the fuel pressure regulator and return relocated to the cold start injector location in the middle of the fuel rail.
Date: Sat, 28 Sep 96 13:53:32 UT
From: "BRAD BEDELL" (Bradbedell@msn.com)
Subject: fuel rail
Hello everyone,
On the fuel rail mod, I going monday to get a parts list for the mod I did. I
will have "Earls" part #'s and a brief description on the way I did it.
Tools- 12 X 1.25 tap w/ proper drill bit
5/16 drill bit (apx 16 " long) to drill the center of rail
1/8 npt tap and plug to plug end of rail
Anyone who has taken the rail out will see that toyota machined the rail out
from the passanger side of the rail (right)
all I did is remove the plug and drilled the rail out. This went from apx 5mm
to 8mm not alot of difference, but enough that I feel better.
brief list w/ out part #'s
3 -6 to 12x 1.25 fittings
1 -3(m) to 1/8 npt (f) 90 deg fitting
1 tee -6 (2male ends and one female end female end to rail)
apx 5 feet of -6 line
3 -6 straight connectors (hose to male fitting)
1 -6 90 deg (f) to hose
1 12x1.25 tap w/ proper drill bit
1 1/8 npt tap w/ proper bit
1 5/16 drill bit apx 18" long ( to drill out rail)
1 1/8 npt plug/ hex end or slotted
1) remove fuel rail, injectors, bolts, regulator, etc
2) drill out plug on (passanger side of rail (right side))
3) using 5/16 drill bit (long) drill out center of rail (fuel path)
Be careful and keep this wet w/ oil so not to overheat bit/and keep the
path smooth.
4) drill out regulater hole, and fuel line hole.....careful not to hit
threads
5) drill & tap cold start injector feed (on rail) to 12X1.25 (careful here
not much material set it up in a drill press or like)
6) tap first 1/2 inch of rail and plug the newly bored hole for 1/8 npt plug
(or weld end shut) and grind it to origional length/ (no extra clearance on
the rail)
7) clean all metal shavings (should be done before plugs installed)
8) install 12 x 1.25 to -6 fittings in two end (factory holes)
9) install fuel psi regulator in center hole (one you drilled) again be
careful not much material here/ (watch it you guys who think tighter is
better)
10) take the tee and drill through the side of it and tap it for 1/8 npt
(only half of the tee not all the way through)
11) put 90 deg 1/8 npt to -3 fitting in (tighten) align toward coldstart
injector
12) fit hose to rail ( 90 deg -6 on right side and tee on left)
13) install -3 line to fitting/ and re assemble injector rail
14) install rail and cold start injector line
15) remove banjo bolt from fuel filter and remove fuel line from rail to
filter
16) put -6 to 12 X 1.25 fitting in filter
17) route -6 line from filter to rail
test system for leaks
also another note, sorry to make this so long, this would be a good time to
get your injectors balanced...everyone seems to be overlooking this fact...if
you don't balance the fuel, it dosen't matter ifyou balance the air...it still
will run lean in a cylinder..(I sure hope this dosen't start any debates if
you have any questions call RC Engineering (310)320-2277 )
This cost me apx 125.00 w/ shipping (AND WAS WORTH THE MONEY!!)
The whole rail thing cost me apx 150.00 w/ all the tools (WAS IT WORTH IT??
well I haven't changed any more pistions since)
This should not be a too difficult project for you w/ a little mechanical
ability...if you tend to leave hoses, belts, and nuts loose, I would not try
it let someone who can handle it do it.....However the fuel rail isn't too
expensive at Toyota, but it does take a couple of weeks to get it
in..(ex-toyota employee)
Sorry so long, hope this helps anyone
Bradbedell@msn.com
91 MKII turbo
88 ALL-Trac Turbo