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  302 Ford Engines

Ford 302 V-8 Engines 

  302 "F" 2V
302 "J" 4V
302 "G" 8V
Tunnel Port
302 "G" 4V
Engine Type 8 cylinder
90 degree,
Overhead Valves (OHV)
8 cylinder
90 degree,
Overhead Valves (OHV)
8 cylinder
90 degree,
Overhead Valves (OHV)
8 cylinder
90 degree,
Overhead Valves (OHV)
Displacement 302 cu.inches (CID) 302 cu.inches (CID) 302 cu.inches (CID) 302 cu.inches (CID)
Maximum torque

310 lbs./ft. @ 2,800 RPM
295 lbs./ft. @ 2,600 RPM
242 lbs./ft. @ 2,000 RPM

310 lbs./ft. @ 2,800 RPM 310 lbs./ft. @ 2,800 RPM 290 lbs./ft. @ 4,300 RPM
Maximum Horsepower 210 BHP @ 4,400
220 BHP @ 4,600 RPM
210 BHP @ 4,600 RPM
141 BHP @ 4,000 RPM
230 BHP @ 4,800 RPM

250 BHP @ 4,800 RPM
(Shelby Cobra GT 350 only)

240 BHP @ 5,000 RPM

420 BHP @ 8,000 RPM
(Trans Am Version)

290 BHP @ 5,800 RPM

470 BHP @ 9,000 RPM
(Trans Am Racing Version)
Firing Order 1-5-4-2-6-3-7-8 1-5-4-2-6-3-7-8   1-5-4-2-6-3-7-8
Bore & Stroke 4.004" X 3.0028" 4.004" X 3.0028" 4.004" x 3.0028" 4.004" x 3.0028"
Compression Ratio 9.01:1
(pre 2/68)
(2/68 to 1970)
10.1:1 10.5:1  10.5:1 (1969-70)
Compression Pressure   130-170 psi    
Mains 2-bolt 2-bolt 4-bolt cross bolted

Autolite 2300-A (2V)

 automatic choke

Autolite 4300 (4V) 

automatic choke

Autolite 4300-A (2x4V)
 automatic choke

Holley 4160 (2x4V)
manual choke
Holley 4150-C (4V)

manual choke
Size of Carburetor     Autolite 435x2 CFM

Holley 540x2 CFM
Fuel regular gas premium gas premium gas premium gas
Intake Manifold cast iron cast iron

(Shelby Cobra only)
special aluminum with pushrods in intake aluminum
Valve train hydraulic lifters hydraulic lifters hydraulic lifters solid adjustable lifters
Intake 1.773"-1.788"


2.01" 2.225" -2.375"
Exhaust 1.442"-1.457" 1.442"-1.457" 1.53" 1.647"-1.662"
(early 1969)
Distributor single point
vacuum advance
single point
vacuum advance
single point
vacuum advance
dual point 
vacuum advance
RPM limits 
Point Gap .017"-.021" .017" for IMCO
.021" for Themactor
  .020" both sets
Initial Ignition Timing 6 degrees 6 degrees   16 degrees
Dwell @ idle RPM 24-29  (manual)
26-31 (automatic)
26-31 for IMCO
24-29 for Thermactor
Spark Plugs Autolite BF-42
Autolite BRF-42
Autolite BF-42 Autolite BF-42 Autolite AF-32
Autolite ARF-32
Plug Gap .032"-.036" .032"-.036"   .035"
Long Block Weight
in lbs.
475 475 475 500
Tunnel Port 302 
After winning the Manufacturers Trophy in 1966 & 1967, the Ford team had some stronger competition for 1968. Chevrolet was about to get involved in a very big way. Vince Piggins at Chevrolet saw the great potential for sales of Camaros by racing in the Trans Am series. He committed to SCCA that Chevrolet would support the series.

The 302 Camaros had a clear horse power advantage over the Mustangs. The ports and valves in the 289 heads were too small to produce the horsepower needed. The best head available was the high performance heads with small valves and ports. The new Ford 302 would be ideal for Trans-Am racing since it was under the 305 cid limit of class limit, but the hi-po heads would be too restrictive on the longer stroke of the 302 block. Ford started a crash development program to fix the problem at Ford Engine and Development during 1967. This effort would lead to development of the Boss 302 in 1969. It was also during this development time that the famous Ford "tunnel port head" came about. There was a "pull out the stops" effort to maximize the flow of the heads. The Ford engineers developed a brand new head with straight intake ports and the pushrod tubes running through the port. In the past the ports would twist around the pushrods. The intake valves were a huge 2.12" compared to 1.77" for the 289. The exhaust valves were 1.54" versus 1.44". Each port feed an individual cylinder. These heads became known as "tunnel ports." On paper this combination of the head design with the new 4 bolt main 302, looked unbeatable.

The overhead valve pushrod engines competed for space with the intake ports. Conventional design places the pushrods along side a rectangular shaped intake port. These ports also steer around the pushrods. The Ford tunnel-port design runs the pushrod through the center of a round intake port, within a thin wall tube. The ports flow better due to their round shape and straight path. This design was first used on the 427, and then in 1968 on a special 302. 

These round intake ports were 3.8 sq. in. in area at the intake manifold face. The Tunnel Port 302 cylinder heads feature 2.12" intake and 1.54" exhaust valves. By comparison, the 289 High Performance engine used 1.78" intake and 1.44" exhaust. These large valves completely filled the wedge shaped combustion chamber. The exhaust ports were larger than normal 289 & 302 heads. Two 540 cfm Holley's sat on a high-rise aluminum manifold. Two Autolite 4300 carburetors were used on the street version. 

The race version featured domed pistons, yielding a compression ratio of 12.5:1, a solid lifter camshaft and forged steel crankshaft. The nodular cast iron rocker arms were shaft mounted, similar to those used on the Y-block V-8. Lubrication for these shaft mounted rockers required a special block with revised oil passages. Also used was a special road racing style 8-quart oil pan. Some used an early transistorized ignition. 

The street version used flat-top piston, for 10.5:1 compression, and a hydraulic camshaft. The engine was complete with thermactor emissions control hardware, 289 Hi-Po style exhaust manifolds, and a thermostatic clutch radiator fan. SCCA rules required 1,000 engines in production for 1968 Trans Am homologation. As used in Trans Am competition the engines produced approximately 420 bhp with an 8,500 rpm redline 

You have to finish races to win them, though. The tunnel port engines just didn't have lasting power. Engine failure after engine failure keep the Mustangs from finishing the races. Penske's Camaros dominated the 1968 Trans-Am racing. 

1968 Tunnel Port 302 Cylinder Head Casting number C8FE-6090-A 

The Boss 302

After a very disappointing 1968 racing season Ford designed a new engine specifically for F.I.A. Trans Am competition in 1969, the Boss 302. The engine was introduced on April 17, 1969. About 8,600 Boss 302 engines were built. 

The Boss 302 block was essentially the next generation of 289 High Performance hardware, but features a forged steel crankshaft, 4-bolt main caps, and screw-in freeze plugs. These modifications were developed as part of the 302 Tunnel Port design. Street versions used connecting rods similar to the 289 Hi-Po while the Trans Am version used heavier 7/16" bolts. 

The real magic of the Boss engines came from the canted-valve Cleveland cylinder heads. While the Boss 302 was normally considered a 302 with 351 Cleveland heads, these canted-valve heads were used first on the Boss before the rest of the Cleveland was developed. As fitted to the Boss, the heads feature steel spring seats, screw-in rocker studs, pushrod guide plates, and adjustable rocker arms. The Boss 302 and 351C-4V head casting were the same except for a minor difference in water passages. Camshafts were quite similar to the 289 Hi-Po. Due to the larger Cleveland-style heads, the Boss 302 weighs somewhat more than the normal 302, tipping the scales at 500 lbs. 

The street version was conservatively rated at 290 HP @ 5800 RPM. During the '69 Trans Am season the racing engines were putting out 470 bhp at a 9,000 rpm redline. 

Designed for the road racing environment, the engines featured a scraper style windage tray. This tray attached to four special main cap bolts with small threaded holes in their heads. 

#Ford listed a Boss 302 in 1971 in its brochures. The engine was not actually offered. The next version of the Hi-Po engine was the Boss 351.

This page was created on June 6, 2000, it was last updated on Friday, January 19, 2001 .

Information is from several Ford sources.