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    Haibeck Automotive Technology

Top End Porting

The plenum ports are opened up to the maximum that the castings will allow. The septum wall between the primary and secondary ports is removed from the plenum. The injector housing ports are enlarged to match the plenum ports. The tops of the injector housing ports are knife edged to blend the flow from the plenum. The fuel injector bosses are reduced in size. On the '90 - '92 engines the primary fuel injector bosses are removed. The throttle body is enlarged from the stock 59 mm to 63 mm. Finally, in the air horn, intrusions related to the alternator and air conditioning compressor locations are reduced in size.