The stock turbo fuel injection system will support only around 275
horsepower before the injectors are maxed out. Once you reach this
point you have a few choices:
- JWT 450 package: Uses an 88-89 (turbo or non) comptuer than JWT
modified to run 420cc/min injectors with a 1993 Ford Cobra air flow
meter(cheaper, more reliable, and less pressure drop than stock unit).
This also gets you the tweaked JWT fuel and ignition timing maps, which
are very nice. At a cost of $600 (plus $250-600 for the injectors and
around $200 for the Ford air flow meter) it is the cheapest way to get
lots of extra power capacity in your fuel system.
- Reprogram your own computer: basically what JWT does, do it and tune
your own Nissan computer. The basic information you need to do your
own hex editing and prom burning is available here.
- Stand-alone systems: Motec, Electromotive, SDS, Haltech, and others.
These are stand-alone fuel and ignition systems that are fully programmable
and can use any components you want(ie. any size injectors). They require
lots of work and knowledge to install, more than most people posess. But
they are the most adjustable and best way to go. You can get into an SDS for
around $1000, Tec3 for around $2000, and Motec starting at $3k. Some of
these systems will require all new sensors and lots of custom made parts.
But compare to the cost of the JWT 450 package and you'll see that for just
a hair more money up front you can have far more potential down the road.
- FMUs: Highly not reccomended. These are fancy fuel pressure regulators
that raise fuel pressure faster than the normal 1:1 ratio. Normally
at 10psi manifold pressure your fuel pressure will be the set value plus
the 10psi to account for the manifold pressure. An FMU will raise fuel
pressures more than 1psi for each 1psi of boost - ie. you'll be running
20psi above normal fuel pressure at 10psi manifold pressure.
While they can be made to work, they are a band-aid and not suitable for
any significant gains in power. Avoid at all costs, they are bad.
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