FAQ for High Performance Fuel Rails

What's all this 'pintle' stuff about?
Nissan made a design change to go to a pintle-less style injector in '93 for NAs and '94 for TTs. Pintle-less designed injectors can meter fuel more accurately because they have less moving mass. Injectors are considered to be an on/off device, but there is a very brief period of time where the 'valve' or the pintle is in motion from open to close or close to open. This transit time effects performance of the injector. A pintle-less design can open and close the valve faster with less transit time. Considering at 6000 RPM, there are 50 injection events per second this transit time becomes troublesome for proper fuel metering. It cannot be made shorter and consumes a higher percentage of time out of the 'cycle' as RPMs go up.

Here is what the early pintle style injector looks like installed in a stock fuel rail:

The connector is rather square.

Here is what the later pintle-less style injector looks like installed in a stock fuel rail:

The connector is more oval shaped.

So then what's the deal with the lower intakes?
The OEM fuel rails have a different design for the pintle versus pintle-less injectors. Therefore the way the fuel rail fits on the lower intake is different. So to put '95 injectors on a '90 Z32 for example, you would have to have the fuel rail be designed to fit on the earlier lower intake like the 300 Degree High Performance Fuel Rails, or send the '90 lower intake off for machining to accept the '95 OEM fuel rails.

What OEM type parts do I need besides the AN fuel line and fittings?
300D-012-01 fits Sard/PE injectors onto an early model lower intake

  • 14033-30P02 - plenum to lower intake gasket
  • 14719-30P05 - EGR gasket (2 req'd)
  • Upper injector insulators provided in kit
  • 16635-10V10 - lower injector insulator (6 req'd)
  • Sard injector connectors
  • Sard injectors (P/N 63507) are supplied with the correct O-rings while PE injectors are supplied with the 'Nissan' O-rings. If you bought PE injectors you'll have to source OEM Mazda O-rings for the secondary injectors of the RX7 (FD3S). Injectors should look like this:

    300D-012-02 fits Sard/PE injectors onto a late model lower intake

  • 14033-30P03 - plenum to lower intake gasket
  • 14719-30P05 - EGR gasket (2 req'd)
  • Upper injector insulators provided in kit
  • 16635-88G00 - lower injector insulator (6 req'd)
  • Sard injector connectors
  • Sard injectors (P/N 63507) are supplied with the correct O-rings while PE injectors are supplied with the 'Nissan' O-rings. If you bought PE injectors you'll have to source OEM Mazda O-rings for the secondary injectors of the RX7 (FD3S). Injector image above.

    300D-012-03 fits OEM pintle-less injectors onto a late model lower intake

  • 14033-30P03 - plenum to lower intake gasket
  • 14719-30P05 - EGR gasket (2 req'd)
  • 16635-53J00 - upper injector insulator (6 req'd)
  • 16635-88G00 - lower injector insulator (6 req'd)
  • 16618-53J00 - lower injector O-ring (6 req'd)
  • 16618-10V05 - upper injector O-ring (6 req'd)
  • NISMO/Nissan injectors
  • NISMO/Nissan injector connectors

    300D-012-04 fits OEM pintle-less injectors onto an early model lower intake

  • 14033-30P02 - plenum to lower intake gasket
  • 14719-30P05 - EGR gasket (2 req'd)
  • 16635-53J00 - upper injector insulator (6 req'd)
  • 16635-10V10 - lower injector insulator (6 req'd)
  • 16618-53J00 - lower injector O-ring (6 req'd)
  • 16618-10V05 - upper injector O-ring (6 req'd)
  • NISMO/Nissan injectors
  • NISMO/Nissan injector connectors'

    5-25-2010 Notice to High Performance Fuel Rail purchasers from March 2010 to July 2010 for 300D-012-04 kits. We've had reports of some threading problems for the AN-6 fittings on the ends. If your fittings don't thread almost all the way in like this:

    Please contact us for resolution, the fittings are not seating properly and will leak.

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