Editing Ford small block engine (section)

===4-Bolt main bearing caps===
====GT40====
In response to a new Le Mans regulation limiting engine displacement to {{cvt|5|L|cuin|0}}, Ford added an extra 1/8-inch of piston travel to the 289 Hi-Performance V8, yielding the {{cvt|302|cuin|cc|0}} block. It featured heavy-duty four-bolt main bearing caps and pressed-in core plugs, and was topped with Gurney-Weslake aluminum heads.{{citation needed span|text=About 50 blocks were made.|This unsupported boldface claim needs a reliable citation.|date=May 2024}}

====Tunnel-Port 302====
The 302 "Tunnel-Port" engine was envisioned as the motor that would bring Ford a third Trans-Am Championship title in 1968.

Starting with a 1967 GT40 block, Ford fitted cylinder heads with a design based on their NASCAR 427 heads. The intake ports were straight, instead of snaking around the push rods, while the push rods went through the center of the ports (thus the name "Tunnel-Port"). This configuration also enabled larger valves to be used. The 302 tunnel-port motor was topped off with an aluminum dual quad intake.

Shelby [[dynamometer]] runs showed the engine was capable of producing {{cvt|440|–|450|hp|kW|0}}, and of operating in a very high rpm band (8000+).

====Boss 302====
[[File:Boss302Engine.jpg|thumb|[[Ford Boss 302 engine|Boss 302 engine]]]]
{{main|Ford Boss 302 engine}}

Officially called the "302&nbsp;H.O.", the Boss 302 was a performance variant of the small block designed to help Ford wrest back the 5-liter Trans-Am racing championship from the [[Camaro Z28|Camaro Z/28]]. Conceived of by chief engineer Bill Gay and realized by Bill Barr, it put large-port, large-valve, quench-chambered, free-flowing cylinder heads adapted from the design destined for the 351 Cleveland, which debuted in 1969,<ref>{{cite web |last1=Holdener |first1=Richard |title=Ford Boss 302 Engine Build - Build A Better Boss - Tech |url=https://www.motortrend.com/how-to/mdmp-1011-ford-boss-302-engine-build/ |website=MotorTrend |access-date=13 February 2023}}</ref> on a special racing block, bringing rated power to {{cvt|290|hp|kW|0}}. According to some reports, the canted-valve, deep-breathing, high-revving engine could produce more than {{cvt|310|hp|kW|0}}, although it was equipped with an electrical revolution limiter that restricted maximum engine speed to 6,150&nbsp;rpm. The 302&nbsp;H.O. borrowed both components and ideas from the 289 HiPo. A strong 4-bolt main bottom end, thicker cylinder walls, steel screw-in [[core plug]]s, aggressive forged-steel crank, special HD connecting rods, and Cleveland-style forged pistons were geared to racing. The [[Boss 302 Mustang]] was offered only for the 1969 and 1970 model years. In the January 2010 issue of ''Hot Rod'' magazine, a Boss 302 engine built to the exact specifications, settings, and conditions of the original engine was tested. It produced {{cvt|372|hp|kW|0}} at 6,800&nbsp;rpm (650&nbsp;rpm over the original engine's redline) and {{cvt|325|lbft|Nm|0}} of torque at 4,200&nbsp;rpm.<ref name="hrm-shootout">{{cite web |author=<!-- not stated --> |date=2009-11-30 |title=Muscle Car Engine Shootout - Chevy Vs. Ford Showdown |url=https://www.hotrod.com/how-to/hrdp-1001-muscle-car-engine-shootout |website=hotrod.com |location= |publisher= |access-date=}}</ref>