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| Manufacturer | Ford Motor Company |
|---|---|
| Production | 1941 - 1996 (US) 1960 - present (AUS) 1961 - 1991 (ARG) |
| Block alloy | Cast iron |
| Head alloy | Cast iron |
| Valvetrain | OHV |
| Fuel system | Normally aspirated and Turbo charged |
| Fuel type | Gasoline |
| Cooling system | Watercooled |
Ford's first straight-6 engine was introduced in 1906 in the Model K. Production ended in 1907. Henry Ford did not like this car, which had a habit of tearing its transmission up. The next Ford six was introduced in the 1941 Ford. The company continued producing straight 6 engines until they were replaced in the mid-1990s by more compact V6 designs. However, Ford's Australian Branch manufactures these engines for their Falcon range to this day.
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First generation
The first generation Ford in-line six-cylinder (L6) engines were all of the flathead type. They were the G- and H-series engines of 226 cu in (3.7 L) used in cars and trucks and the M-series of 254 cu in (4.2 L) used in larger Ford trucks and for industrial applications.
226
Introduced with the 1941 model year, the first Ford six (designated G-series) displaced 226 cu in (3.7 L) and produced 90 hp (67 kW), the same as the Flathead V-8 that year. Like the V-8, it was also a flathead or L-head engine. In 1948, Ford raised the compression of the flathead six (designated H-series or Rouge 226) so that it generated 95 hp (71 kW) and 180 lb·ft (244 N·m) of torque. The G- and H-series engines were used in the full-size Ford cars and trucks to replace the smaller 136 cu in (2.2 L) Flathead V8 that were used with the 1937 Ford. Ford discontinued production of the H-series engine with the 1951 model year.
254
A 254 cu in (4.2 L) version of the flathead six (designated the M-series or Rouge 254) was used from 1948-53 in F6-series Ford trucks (COE, Dump, semi-, etc.), and small Ford school buses. The M-series engine produced 110 hp (82 kW) and 212 lb·ft (287 N·m). of torque. They were also used in miscellaneous industrial applications. e.g., to power water pumps for irrigation purposes and within wine-producing farms to manage risk by powering giant frost-control propellers on stands in the middle of rows of grapes.
Second generation
The second generation was produced from 1954 through 1964.
215
A completely new OHV six was offered for the 1952 F-series. It displaced 215 cu in (3.5 L) and produced 101 hp (75 kW). It was also used in the 1952 Ford full-size cars.
223
The 215 grew to 223 cu in (3.7 L) for the 1954 F-series. Output was now 115 hp (86 kW) (as the "Mileage Maker" in the trucks) and 120 hp (89 kW) in the 1955 Ford cars. Power was up to 137 hp (102 kW) in the 1956 trucks.
262
A 262 cu in (4.3 L) version was also produced. The 262 was built from 1961-64 for use in Heavy Duty Ford Trucks. This engine was also used for industrial applications.
Third generation
| Also called | Falcon Six |
|---|---|
| Production | 1960 - 1984 |
| Dry weight | 385 lb (175 kg) |
| Power output | 88 hp (66 kW) - 155 hp (116 kW) |
The third generation was produced at the Lima Engine plant in Lima, Ohio from 1960 through 1984. Officially dubbed the Thriftpower Six, this engine line is sometimes referred to as the Falcon Six. Note: Car companies including Ford, switched from gross ratings to net horsepower and torque ratings in 1972 (mainly because of the emissions laws being enacted nationwide at the time). Changes in engine compression and emissions controls make it difficult to compare engines from various production years (especially pre-1972).
144
| Production | 1960 - 1964 |
|---|---|
| Bore | 3.5 in (88.9 mm) |
| Stroke | 2.5 in (63.5 mm) |
| Displacement | 144 cu in (2.4 L) |
| Power output | 84 hp (63 kW) @ 4200 RPM |
| Torque output | 134 lb·ft (182 N·m) @ 2000 RPM |
| Compression ratio | 8.7:1 |
The 144 cu in (2.4 L) engine was first introduced in the 1960 Ford Falcon. The 144 was made from 1960 through 1964 and averaged 90 hp (67 kW) during the production run. While not known for being powerful or a stout engine, it proved to be economical and could get fairly good gas mileage for the time (up to 25-30mpg). This small six was the basis for all the Ford "Falcon" straight-six engines. The intake manifold on this series of engine was cast integrally with the cylinder head (this design was also used by Chevrolet with their third generation inline six); as a result, they could not be easily modified for greater power. This engine had four main bearings and can be identified by the three core plugs on the side of the block.
This engine was used in:
- 1960 - 1964 Ford Falcon
- 1960 - 1964 Ford Ranchero
- 1960 - 1964 Mercury Comet
- 1961 - 1964 Ford E-Series
170
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| Production | 1961 - 1972 |
|---|---|
| Bore | 3.5 in (88.9 mm) |
| Stroke | 2.94 in (74.7 mm) |
| Displacement | 170 cu in (2.8 L) |
| Power output | 105 hp (78 kW) @ 4400 RPM |
| Torque output | 156 lb·ft (212 N·m) @ 2400 RPM |
| Compression ratio | 9.1:1 |
In 1961 the 170 cu in (2.8 L) became an option for the Falcon line. The 170 was a stroked version of the 144, changing the stroke from 2.5" to 2.94". The original 1964½ Ford Mustang used a 101 hp (75 kW) version. The Econoline van and Ford Bronco received a heavier duty version with mechanical valve lifters. This engine had four main bearings and can be identified by the three freeze (core) plugs on the side of the block. Later versions of this engine have seven main bearings. The 170 was dropped from production in 1972.
200
The 200 engine model was introduced in the middle of 1963 and shared the four main bearing design used in the 170 engine. Early 200s can be identified by three freeze (core) plugs on the side of the block.
Beginning in 1965 the 200 CID engines were upgraded to seven main bearings to reduce harmonic vibrations and increase durability. The 1965 and later engine can be identified by 5 freeze (core) plugs on the side of the block and the casting code C5DE-H. Starting in 1966 a six bolt bell housing flange block was introduced.
Beginning in 1980 the block was redesigned with a bell housing flange and a low mount starter that is very similar to the small block Ford V8. This version is easily identified by its low-mounted starter location down by the oil pan rail and is referred to as the Big Bell 200. The big bell design is uncommon but sought after by Inline six performance enthusiasts because it can be modified to accept a Ford small block V8 six bolt bell housing.
The 1965 Mustang used this engine as standard with 120 hp (89 kW). The Mustang continued to use the 200 as its base engine until it was dropped in 1971.
When Ford launched the third generation Fox body Mustang in 1979, the original engine line up included the Cologne V6. The same engine was also offered in the hugely successful Ford of Europe Capri Mk II. The 2.8L V6 engine was a popular option for the US Mustang and the European Capri MkII and as a result the Cologne engine plant could not meet the demand for engines for both Continents.
So, the Cologne 2.8L V6 was dropped from the engine lineup in the middle of the 1979 production year and replaced with the 200cid Falcon inline six, which was now referred to as the 3.3L engine. The engine and front suspension K-member was transferred from the Fairmont model which helped reduce costs instead of having to redesign the Mustang for a different engine.
The 200 was used in the Ford Maverick and Mercury Comet models, and continued on in the Ford Fairmont and Mercury Zephyr until the Fairmont and Zephyr models were retired at the end of the 1983 model year and replaced with the Ford Tempo and Mercury Topaz.
The Ford Granada and Mercury Monarch offered the 200 inline six as part of their engine lineup from 1975 to 1982 when they were replaced in 1983 by the Ford LTD and the Mercury Marquis. These two models used the engine from 1983 to 1984 when it was replaced by the 3.8L Essex V6.
Ford was also having problems meeting demand for its 2.3L OHC engine which was used in a multitude of models worldwide.
In anticipation of another engine shortage, Ford's Lima Ohio engine plant, which was already producing the 2.3L OHC engine, decided they could modify the Falcon inline six block casting molds to remove cylinders 4 and 5 to create a 4 cylinder engine. An aluminum high-swirl cylinder head was developed, and the motor was designated the 2.3L HSC to help differentiate it from the same displacement 2.3L OHC design. This motor shared many common parts with the 200/3.3L inline six, and it is common for persons rebuilding their 200/3.3L inline six motors to use the 2.3L HSC pistons as a cheap replacement.
250
The 250 cu in (4.1 L) straight six was an engine option offered in 1969 in the Mustang, and 1970 in medium-sized Ford cars (Maverick). The 250 was a stroked 200, made by changing the stroke from 3.126" to 3.91". Output was 155 hp (115 kW) in the Mustang, and became the base engine in 1971. Power was re-evaluated at 98 hp (73 kW) for 1972 (due to power rating changes) and 88 hp (66 kW) the next year. The last year of production for the 250 was 1980. This engine had seven main bearings, and can be identified by the five freeze (core) plugs on the side of the block. The block uses a low mount starter and six bellhousing bolts, sharing its bellhousing with the Windsor V-8s 302-351W, late (1965-68) 289, 351 Cleveland, early 4.6, and the 240-300 CID Ford Six.
Restoration and restomodstatus
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The rising cost of fuel has increased the interest in the Falcon six design, and the engines have been gaining in popularity in recent years. Many Falcon and Mustang owners who used to replace their car's original inline six engine with a V8, are now keeping their inline sixes for the better fuel economy the inline six motor offers. A number of restoration and performance parts vendors now stock parts for people restoring their inline six motors.
Due to increased popularity of the Falcon six engine, the desire for improved performance, and difficulty in finding good quality used parts for an engine that has been out of production for 25 years, in 2005 the company Classic Inlines designed a modern aluminum head based on the Australian 250-2v head but with raised intake ports, high swirl combustion chambers, and larger valves. One of the features of the new head are pads cast into the top of the intake runners, which allows owners the ability to machine the head to accept modern electronic fuel injectors for direct port fuel injection.
Not only does the new head improve power output, but also the high-swirl design improves fuel mixing in the cylinder for a more complete burning of the air fuel mixture, resulting in reduced emissions output.
Ford of Australia Inline Six
Starting in 1960, Ford of Australia used the same inline six engines as North America, featuring the 144 cid and 170 cid models. Also as in North America, a 200 cid motor was added in 1965.
In 1968, Ford of Australia increased the deck height of the design to make room for increased crankshaft stroke, and 188 cid and 221 cid models were added to the lineup.
In 1970, Ford of Australia developed the 250 cid motor. the head was of the same design as previous models, with an integral intake catering for 1 single barrel stromberg carburettor. In the configuration, the falcon six was rated at 155 hp (116 kW). Around this time Ford of Australia also developed the '2V' cylinder head, which in all respects was similar to the previous integral "log head" intake, with the exception of a removable aluminum intake which mounted a Stromberg 2-v carburetor. To take advantage of the much improved breathing ability that the removable intake brought to the new head, the 250-2v also mounted a much better breathing exhaust manifold. The result was the engine being rated at 170 hp (127 kW).
For years the 250-2V cylinder head was very popular for racing and many have been imported to North America, where owners of cars with the Falcon inline six have upgraded their engines with the better cylinder head.
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In 1976, Ford of Australia replaced the 250 engine with a new block and head design, which was based on a taller and wider block with a cast iron crossflow head design. This engine was offered in the Ford Falcon XC in Australia. Whereas the previous integral "log head" inline six motor borrowed from the Ford FE engine family design, the new crossflow motor borrowed from the Ford 351 Cleveland engine family. A common upgrade for a crossflow head engine is to use 351 Cleveland roller tip rocker arms.
Ford of Australia continued the Crossflow design in 1978, but now an aluminum head casting was featured. The alloy head was used to improve warm up time and reduce fuel consumption and emissions. The iron head versions were fitted with a Stromberg carburetor, and the aluminum head versions were fitted with a Webber carburetor, which had improved consumption over the Stromberg.
Later, a Bosch Jetronic fuel injected version with direct port fuel injection was offered, and was only available as an aluminium 4.1 L from the XE Falcon onwards. There were changes to the carburetor-based engine to accommodate the Electronic Fuel Injection system. The compression ratio on the 4.1 L was 8.89:1. The cylinder head intake ports had been modified to provide clearance for the injectors, and a new intake manifold was designed and many other changes were made in the engine bay to accommodate the new fuel system.
- Power at Specified RPM (DIN) Pre '86 running on Leaded Fuel
- 3.3 L 90 kW (121 hp) @ 4100 rpm
- 4.1 L Carburetor 103 kW (138 hp) @ 3750 rpm
- 4.1 L E.F.I Engine 120 kW (161 hp) @ 4000 rpm
- Torque at Specified RPM (DIN) Pre '86 running on Leaded Fuel
- 3.3 L 240 N·m (180 lb·ft) @ 2500 rpm
- 4.1 L Carburetor 316 N·m (233 lb·ft) @ 2400 rpm
- 4.1 L E.F.I Engine 333 N·m (246 lb·ft) @ 3000 rpm
- Power at Specified RPM (DIN) ADR 37 compliant engine running on Unleaded
- 3.3 L 89 kW (119 hp) @ 4000 rpm
- 4.1 L Carburetor 99 kW (133 hp) @ 3600 rpm
- 4.1 L E.F.I Engine 123 kW (165 hp) @ 4000 rpm
- Torque at Specified RPM (DIN) ADR 37 compliant engine running on Unleaded
- 3.3 L 238 N·m (176 lb·ft) @ 2200 rpm
- 4.1 L Carburetor 303 N·m (223 lb·ft) @ 2000 rpm
- 4.1 L E.F.I Engine 328 N·m (242 lb·ft) @ 3000 rpm
In 1988, the inline six engines offered in the EA Falcon featured a new Single Over Head Cam (SOHC) crossflow aluminum head design. The camshaft and auxiliary shaft are driven by a 'Duplex' chain. The duplex chain drives the distributor and the oil pump shafts. The camshaft is supported on the cylinder head by using 'topless' bearings. Bearing liners are not used. The camshaft is held in position using valve spring pressure. Hydraulic lash adjusters mounted on the rocker arms are used to provide zero valve lash. As with all previous and current models, the block is cast iron, but with a reduction in the cylinder bore to try to help reduce emissions.
The SOHC engines were offered in 3.2L and 3.9L sizes with multipoint fuel injection or throttle body injection. In 1990, the 3.2L TBI version was discontinued, and in 1991 the 3.9L's displacement was enlarged to 4.0L and the engine was rated at 148 kW (198 hp).
Ford of Australia redesigned the inline six again in 1998, and increased the main bearing size and added a ladder style main stud girdle integral with the oil pan to increase low end rigidity. The engine also received variable cam timing technology, which can advance or retard cam timing depending on engine rpm, which gives a much broader power band.
In 2002 the engine received double overhead cams (DOHC) with variable cam timing as the Barra inline six motors and, depending on the version of engine, were offered in the 2002 BA Falcon, Fairlane, and the SX Territory. Currently the BA 190 powers the Falcon and Falcon "Utes" and the SY Territory since 2005. The BA190 is rated at 255 hp (190 kW) at 5250 rpm and 282 ft (86 m) lbs at 2500 rpm.
There have been some noteworthy performance versions of the DOHC Barra inline sixes.
The Barra 240T, which was a turbocharged, fuel injected, intercooled DOHC inline six producing 322 hp (240 kW) and 332 ft (101 m) lbs of torque, was offered between 2002 and 2005 in the BA Falcon XR6-Turbo.
Top of the line would be the Barra 310FG DOHC VCT motor, which is rated at 310 kW (416 hp) at 5500 rpm and 417 ft (127 m) lbs of torque. It is the first Australian motor to achieve over 100 hp (75 kW) per liter, and produces more torque than any Australian-built engine, including the V8s. It powers the FPV F6, a very high performance version of the Ford of Australia Falcon XR6-Turbo.
Ford Performance Vehicles (FPV) is an in-house factory tuner and serves as the performance division of Ford Australia, similar to the way AMG is to Mercedes-Benz, BMW M to BMW (M3, M5 etc) and HSV to Holden.
Ford of Australia had intended to discontinue production of the inline six motors at their Geelong engine plant in 2010, and replace them with imported Duratec V6s from North America. Due to the drastic increase of oil prices in 2008 and the following economic turmoil, the decision was reversed. Instead, Ford of Australia announced on 20th of November 2008 that 21 million Au dollars would be invested in the Geelong engine plant to bring the inline six engines up to date with the current Euro IV emissions standards.
In the EF model Falcon, the standard engine employed a high-energy coil-pack ignition system. However, the EL falcon used a distributor/coil ignition setup, as in Falcon models prior to EF.
| Falcon model | Capacity | Induction | Valvetrain | Fuel | Power | Torque | Notes |
|---|---|---|---|---|---|---|---|
| XY, XA, XB | 4.1 L | Carburettor | OHV | Leaded | 116 kW (156 hp) | 325 N·m (240 lb·ft) | |
| XC | 4.1 L | Carburettor | OHV | Leaded | 92 kW (123 hp) | 289 N·m (213 lb·ft) | Crossflow cylinder head |
| XD | 4.1 L | Carburettor | OHV | Leaded | 94 kW (126 hp) | 305 N·m (225 lb·ft) | |
| XE | 4.1 L | EFI | OHV | Leaded | 111 kW (149 hp) | 325 N·m (240 lb·ft) | Bosch LE II Jetronic fuel injection |
| XF | 4.1 L | EFI | OHV | Unleaded | 121 kW (162 hp) | 325 N·m (240 lb·ft) | |
| EA, EB | 3.9 L | EFI | SOHC | Unleaded | 120 kW (161 hp) | 311 N·m (229 lb·ft) | |
| EA, EB | 3.9 L | EFI | SOHC | Unleaded | 139 kW (186 hp) | 338 N·m (249 lb·ft) | EEC-IV Multi-point injection |
| EB series II, ED | 4.0 L | EFI | SOHC | Unleaded | 148 kW (198 hp) | 348 N·m (257 lb·ft) | |
| XR6 ED, EF, EL | 4.0 L | EFI | SOHC | Unleaded | 164 kW (220 hp) | 366 N·m (270 lb·ft) | |
| EF, EL, AU | 4.0 L | EFI | SOHC | Unleaded | 157 kW (211 hp) | 357 N·m (263 lb·ft) | Coil-pack ignition system (EF and AU Only) |
| AU series II & III | 4.0 L | EFI | SOHC | LPG | 143 kW (192 hp) | 362 N·m (267 lb·ft) | Dedicated LPG |
| XR6 AU | 4.0 L | EFI | SOHC | Unleaded | 172 kW (231 hp) | 374 N·m (276 lb·ft) | VCT Variable Valve Timing |
| BA | 4.0 L | EFI | DOHC | Unleaded | 182 kW (244 hp) | 380 N·m (280 lb·ft) | |
| BA XR6 Turbo | 4.0 L | EFI | DOHC | Unleaded | 240 kW (322 hp) | 450 N·m (332 lb·ft) | Garrett GT3540 turbocharger |
| BF | 4.0 L | EFI | DOHC | Unleaded | 190 kW (255 hp) | 383 N·m (282 lb·ft) | |
| BF XR6 Turbo | 4.0 L | EFI | DOHC | Unleaded | 245 kW (329 hp) | 480 N·m (354 lb·ft) | Garrett GT3540 turbocharger |
| FG | 4.0 L | EFI | DOHC | Unleaded | 195 kW (261 hp) | 391 N·m (288 lb·ft) | |
| FG XR6 Turbo | 4.0 L | EFI | DOHC | Unleaded | 270 kW (362 hp) | 533 N·m (393 lb·ft) | |
| FPV F6 model | Capacity | Induction | Valvetrain | Fuel | Power | Torque | Notes |
|---|---|---|---|---|---|---|---|
| BA MkII, BF | 4.0 L | EFI | DOHC | Unleaded | 270 kW (362 hp) | 550 N·m (406 lb·ft) | |
| FG | 4.0 L | EFI | DOHC | Unleaded | 310 kW (416 hp) | 565 N·m (417 lb·ft) |
Fourth generation
| Production | 1964 - 1996 |
|---|---|
| Bore | 4" |
| Stroke | 3.18" (240) 3.98" (300) |
| Displacement | 240 cu in (3.9 L) 300 cu in (4.9 L) |
| Fuel system | Normally aspirated Fuel injection |
| Power output | 120 hp (89 kW) - 170 hp (127 kW) |
| Torque output | 260 lb·ft (353 N·m) |
Produced at the Cleveland Engine plant in Brook Park, Ohio from 1964 through 1996, the 240 and 300 Sixes are well-known for their durability. Simple design and rugged construction continue to endear these engines to a number of Ford enthusiasts to this day. Many have run 300,000 to 600,000 miles (480,000 to 970,000 km) without any more service than standard oil changes.[citation needed]
One example of the engine's sturdy design is the fact that no timing chain or timing belt (both of which can break, causing unwanted downtime or even engine damage) is used. This generation of Ford Six was designed with long-wearing gears for that purpose instead. Few, if any, modern engines use timing gears; belts are by far more common, especially among non-domestic automakers.
Both the 240 and the 300, no matter the application, used a single barrel Carter YF carburetor until the introduction of Electronic Fuel Injection. With proper gearing, many F-trucks and Broncos are able to achieve over 20 mpg with these carburetors, when properly tuned. This was heavily used by Ford's advertising campaign (some television advertisements and written literature even claimed 30 mpg), since the V8 engines in these trucks rarely achieved over 14 mpg.
The fuel economy of the 300 makes the engine a popular choice amongst truck enthusiasts that want both power and economy. The addition of performance parts (such as intake and exhaust manifolds with a four barrel carburetor) place the engine power output near the same levels as the stock HO (high output) version of the optional 351 V8, with little or no change in economy. There are claims of 300s that have had the power output doubled, or even tripled, with less than a single mpg drop in fuel economy.
240
The 240 cu in (3.9 L) six for 1963 - 1970 full sized cars (continued to 74 in fleet models) and 63-77 trucks produced 150 hp (112 kW). In stationary service (generators and pumps) fueled by LPG or natural gas, this is known as the CSG-639.
300
The 300 cu in (4.9 L) six was added for the F-series in 1965. It was essentially a 240 cu in (3.9 L) with a longer stroke. The two engines are nearly identical; the differences are in block dimensions and the rotating assembly. It produced 170 hp (127 kW). The 300 became the base F-series engine in 1978 at 114 hp (85 kW) (hp number changes due to Ford switching to net power ratings in 1971). Power outputs were increased to roughly 122 hp (91 kW) during the early 1980s, before fuel injection was introduced. This became the primary engine of the line, eclipsing the 240. Unlike the Falcon engine, it featured separate intake and exhaust manifolds, which could be easily replaced with aftermarket manifolds offering the promise of even more power, through the installation of larger carburetors and a higher flowing exhaust system.
Also during the late sixties and early seventies, the 300 was used in larger vehicles such as dump trucks, many weighing into the 15,000–20,000 pound (7,000–9,000 kg) range. These 300s were equipped with a higher flow HD (Heavy Duty) exhaust manifold, since the engines were going to be constantly working in the 3000–4000 rpm range. These rare, yet effective, manifolds had higher flow than the electronic fuel injection 4.9 (300) manifolds and some headers.
Engine sizes were converted to metric for 1983, causing the 300 to become the "4.9". Fuel injection and other changes in 1987 pushed output up to 150 hp (112 kW) with 8.8:1 compression. This engine was gradually phased out, ending production in 1996, and was replaced by the Essex V6 in the F-series trucks with their 1997 redesign. However, it was renowned for its durability, low end torque, and ease of service. The 300 4.9 came with the Ford C6 and E4OD transmissions, as well as the Mazda built M5OD 5 speed manual transmission. The 4.9 liter 6 cylinder was built in the Cleveland, Ohio engine plant.
This engine is also used by Stewart and Stevenson in the MA Baggage Tow Tractor (pdf), and Harlan in their standard tow tractors [1], as well as a multitude of other pieces of equipment, such as ski lifts, power generators, wood chippers, tractors, and, until they converted to diesel engines, most UPS trucks. Many UPS trucks still use the 300 to this day.
In stationary service (generators and pumps) fueled with LPG or natural gas, this engine is known as the CSG-649.
The Ford Inline six in racing
The Ford Inline six has had a small though colorful career in racing, which has increased in recent years due to the rising popularity of the motor and the availability of performance parts.
A recent yet giant step in Ford Inline six racing has been performed by McLearran Motorsports in Tucson AZ. The McLearrans, Wil and Kelly, have achieved enough notice that their 1963 Ford Falcon has been seen in several magazines and was scheduled to make an appearance on the show Pinks.
The 1963 Falcon driven by McLearran Motorsports' Kelly McLearran has been dyno tested at 323 rwhp @ 4500 rpm and 502 rwtq @ 2650 rpm. The car has run a best time of 10.89 seconds at 1/4 mile, with Kelly driving.
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External links
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