Dear Horsepower Hungry Customer,

Thank you for purchasing the Vishnu Performance Systems Miata Fuel Rail.  Having spent months testing, tweaking and revising our prototype fuel rails for ideal fuel distribution characteristics, we are confident that our final product will perform to your greatest expectations.  It is a dyno-proven fact that there is more to an upgraded fuel rail than a larger inner diameter, a fuel feed and a return line.  That said, our fuel rail is a testament to the novel idea of innovation, instead of duplication.  Built from premium grade aluminum and machined down to exact tolerances, you will find that our fuel rail is as durable as it is functional.  We stand by our product and welcome any comments that you may have. 

INSTALLATION INSTRUCTIONS

You will need the following in order to install the Vishnu Fuel Rail:

•A roll of Teflon Tape (preferably one designed for gasoline applications)

•12mm Socket wrench (1.6 applications will also requires a 8mm wrench)

            •Flat head screw driver

            •Hose cutters 

            •Standard hex wrenches

STEP ONE

Unbolt the stock fuel rail---  There are three (two in 1.6 liter applications)  12mm bolts securing the stock rail to the cylinder head.  Between the head and the rail, there are also three black plastic spacers (again, just two for 1.6 liter applications).  These spacers seem to be attracted to the innermost and deepest recesses of the engine.  So be careful not to let them get away from you.

NOTE:  In 1.6 liter applications, you will have to remove the idle bypass assembly before the stock rail can be removed.  This involves loosening the four 8mm bolts that secure the assembly to the intake manifold.

STEP TWO

Fuel is fed, by standard fuel line, into the front-most end of the stock fuel rail.  This fuel line goes under intake manifold and is fed from a hard metal fuel line that is fastened to the passenger side frame rail.  Mark this metal line as the FUEL FEED.  The metal line just next to the fuel feed is the FUEL RETURN.  The return line goes under the intake manifold and is routed to the fuel pressure regulator that is secured to the stock fuel rail.  Loosen the hose clamps that secure the fuel lines to the feed and return.  Next, pull off the fuel lines.  They will be stuck on really tight and may require a little twisting in order for them to break free.  With the lines free, the stock fuel rail can be removed completely.  When removing the rail, try to leave the fuel injectors sitting undisturbed in the cylinder head.  If they do get disturbed, be sure to put them back the way they were, o-rings, spacers and all.

STEP THREE

Using the supplied stainless steel bolts, secure the stock fuel pressure regulator to the Vishnu fuel rail.  Route the attached hose under the manifold and to the FUEL RETURN—just like stock. 

STEP FOUR

Test fit the Vishnu Fuel Rail.  Once in place, determine the best placement for the brass feed fittings on each side of the upgraded rail.  Tighten the brass fittings accordingly.  Be sure to use Teflon tape on the threads in order to achieve a proper seal.  Be careful as FAILURE TO DO SO WILL RESULT IN A DANGEROUS FUEL LEAK.  When finally installing the rail, be sure to lubricate the O-rings on the top of the injector with a bit of motor oil.  This will ensure proper injector seating into the new rail.  Be careful not to rip any of these O-rings or get oil into the injector orifice.  When installing the fuel rail bolts, don’t forget those black plastic spacers!

STEP FIVE

Using the supplied fuel line, hose clamps, and brass tee fitting, configure the fuel feed line as depicted in Diagram 1.1.1.  The two feed lines will be routed to each end of the fuel rail.  Be sure to use the supplied hose clamps to secure the fuel lines to the brass fittings.  Again, FAILURE TO DO SO WILL RESULT IN A DANGEROUS FUEL LEAK.  Make sure that there are no nasty kinks in any of the fuel lines.

STEP SIX

Finally, tighten the fuel rail bolts and check all the hose clamps for sufficient tightness.  To test for leaks, turn the ignition key on, off, on, off, on and off.  This will pressurize the fuel system.  Carefully inspect for fuel leaks.  If none are detected, start the car and let it idle.  Again, check for fuel leaks around each injector and at all the brass fittings.  If none are detected, you’re good to go!

TO SEE PICTURES…

Check out Greg Jacob’s on-line picture album at:

http://www.zing.com/album/index.html?id=4292809367

TUNING SUGGESTINGS

The function of the Vishnu Fuel Rail is to provide even fuel distribution to each of the four injectors under a wide range of operating conditions.  No longer is it necessary to tune for the poorest running cylinder.  With improved fueling characteristics, you will find that you are able to advance ignition timing significantly without audible detonation.  However, we encourage you to do so with CAUTION.  Too excessive ignition advance, even without detonation, can damage your engine.  For best results, we suggest using a Dynojet to properly calibrate your fuel and ignition controls.  As a rule of thumb, you will find that additional advance will lead to what appears to be lean-run conditions.  This is because more of the air/fuel mixture is being burned in the cylinder and not in the exhaust piping (where the o2 sensor hangs out).  As a result, you will likely find the need to add additional fuel when running under boost. 

PLEASE RESIST THE TEMPTATION TO ADVANCE TIMING AGGRESSIVELY. 

This will only lead to premature engine failure.  While you may find that you can advance timing by as much as 10 degrees, you may find that peak torque is only necessary with say, 5 degrees of advance.  Finding MBT (Minimum advance for Best Torque) is why Dynojet tuning and exhaust gas temperature monitoring is so valuable for maximum performance and longevity. 

If you have any questions about the installation or tuning process, please don’t hesitate to call me at 925-964-9233.

Happy Tuning,

Shiv S. Pathak

Vishnu Performance Systems