Editing Swirl port SBC heads

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==Overview==
Swirl port SBC heads are often overlooked for any king of performance use. This page will weigh the pros and cons of using them in a "street performance" application.

==History==
The SBC swirl port heads came to be in about 1987. They were used with TBI (throttle body injection) EFI (electronic fuel injection) applications in trucks. Their reason to be was for making good low rpm torque while getting acceptable mileage. This design was first used during the mid-1980s on the GM 2.0L inline four used in the Cavalier - usage of the swirl port was later used on the 4.3L V6 motor in 1985.

The swirl ports are referred to as a vortex chamber where the fuel mixture is twisted (same effect as a tornado).

==Casting numbers and ID==
The 5.7L TBI truck engines used c/n 14102191 and 14102193 heads.

==Design limitations==

===TBI swirl-inducing vane===
[[File:Tbi swirl port vane.jpg|thumb|left|350px|TBI swirl port vane]][[File:Used 193-1.jpg|thumb|left|550px|TBI swirl port vane, paired combustion chambers]]
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===L30 5.0L Vortec head=== 
Some info and photos of the L30 5L Vortec head at [http://www.nastyz28.com/forum/showthread.php?t=56505&page=32 post 478].
{|
|[[file:305_VORTEC_SWIRL_RAMP_CN_059.jpg|thumb|220px|center|305 Vortec L30 casting number 12558059]]
|[[File:305 VORTEC CHAMBER CN 059.jpg|thumb|500px|center|305 Vortec L30 casting number 12558059 chamber]]
|[[File:L31 305 VORTEC HEAD CASTING ID.jpg|500px|thumb|center|305 Vortec L30 casting ID]]
|}

==Modifications and porting==

==Resources==
{{Note1}} As of 05:41, 25 June 2012 (MDT) Mortec is currently unavailable via waybackmachine.
*[http://outintheshop.com/faq/casting/castings2.html SBC head casting number go-to site]
*[http://web.archive.org/web/20080518030656/http://www.mortec.com/ MorTec archived]

[[Category:Engine]]
[[Category:GM]]
[[Category:Cylinder head]]