Ford Falcon GTHO Phase III

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The GTHO Phase III was a modified Ford Falcon muscle car produced by Ford Australia in 1971. Powered by a heavily modified 351 Cleveland motor, with 4 speed top-loader, and Detroit locker 9" differential, the GT-HO was a powerful vehicle. It was also equipped with special brakes and handling package, plus a 36 gallon fuel tank. The Phase 3, as it is referred to by some purists, was very successful in the Australian Touring Car Championship (1973 ATCC winner Allan Moffat drove a Phase 3). It was described by Sports Car World as "...simply one of the best cars in the world, a true GT that could take on Ferraris and Astons on their own terms." EBay Buyer's Guide XY Falcon GTHO Auction

Image:Http://www.bowdensown.com.au/cars/images/FalconPhase3web.jpg

Contents

[edit] Technical data

The GT-HO's 351 Cleveland engine produced over 380 HP (285 kW), and was fitted with a 6,150 rpm rev limiter. With the rev limiter disabled, it would pull 7,000+ rpm, even in 4th gear. The "HO" portion of the name stood for (High Output) However insurance companies refused to insure vehicles under this badge with that abbreviation. To make insurance companies happy the meaning of HO was changed to "Handling Option" which meant these specials had stiffer roll bars and springs. "The Phase 3 was the world's fastest four door production car for many years" and in 1971 it won the Bathurst motor race in the hands of Alan Moffat, however the Chrysler Valiant [1] E49 Charger held the 1/4 mile record in Australia - and the 3.3L (202) 6-cylinder LJ Torana GTR-XU1 defeated the GTHO to win the 1972 Bathurst over 6 hours in the hands of Peter Brock after brake problems and wet weather put paid to the GTHO challenge. It is unknown whether the fastest Falcon was ever tested against other fast 4-doors of the time, namely: the De Tomaso Deauville; Maserati Quattroporte 4.7; Mercedes-Benz 300SEL 6.3; and Monteverdi 375/4 HS, all claimed similar performance figures to the GT-HO.

[edit] Differences between the standard XY GT and the GTHO

[edit] Exterior

The only two external differences between the XYGT and the XY GTHO were the front and rear spoilers. The front spoiler was made of plastic, while the rear spoiler - taken from the 1970 Mustang - was a fibreglass composite type spoiler with die cast hollow aluminium legs, featuring the Ford logo and part numbers cast inside. The fibreglass construction of the original spoilers distinguishes them from replicas or Motorcraft spoilers sold through Ford dealers, which were constructed of aluminium and, at the time, cost roughly one-third of the price of the original.

[edit] Interior

There are only 2 interior differences between the XY GT and the XY GTHO, apart from the fact that the GTHO was only available in 4 speed manual: 1) Choke in dashboard where V8 badge goes in the GT, opposite cigarette lighter. 2) GT-HO decal on glovebox lid instead of GT badges.

[edit] Suspension

  • Rear springs are the same as the 4 speed manual GT. Six leaf - 4 under main spring and one upside down on top of main spring.
  • Front springs longer than the GT to suit the later model type XA stub axle and upper control arm.
  • Upper control arm XA type with 3 stud ball joint not 4 as in XR - XY and shorter length for better handling.
  • Front sway bar that was 1 inch and a rear sway bar that was 3/4 inch thick.

[edit] Brakes

Front discs were the same as the GT but most were fitted with PBR type floating head callipers, instead of the Kelsey Hayes type. Front splash plates were removed Rear drums were finned and shoes were 2.5 inches wide. Rear wheel cylinders were increased in size to .9375 inches to further assist brake balance and to accommodate the larger lining area. A proportioning valve was fitted to the drivers side shocker tower beneath the master cylinder. This works only on the rear brakes. It reduces pressure to the rear since the same amount of hydraulic pressure would cause more braking by the self energising effect of the rear shoes compared to the non energising front discs. A vacuum reservoir was fitted opposite the battery on the inner skirt panel and was a modified vacuum tank that was fitted to the later model LTD with the pop up headlight covers. An extra one way valve outlet was fitted underneath the standard one on the brake booster and a special ‘T’ outlet was on the rear of the intake manifold to accommodate two hoses.

[edit] Differential

The diff housing was the same width as a normal XY type 9 inch housing but there was two differences with it. There was no wedges welded to the bottom of the plates that mount to the rear springs as in the XW - XY - ZC - ZD 9 inch and there were two small mounting plates welded to the housing for the rear sway bar rubbers to mount on. Axles were 28 spline as well as 31 spline . Most 28 spline axle fitted cars had 3.25 : 1 ratio centres. All other ratios were available but most cars were fitted with 3.25 :1 - 3.55 :1 and 3.9:1 There were no spacers on the axles behind the bearing or on the end of the axle tube as in the other 9 inch applications. The diff centre was of a high nodular iron content and there were more casting ribs . Also there was an ‘N’ cast in the centre of the housing as well as the bearing caps to denote high nodular iron content. Diff centre was available in either Daytona type (Normal LSD) or Dapco No Spin (Detroit Locker).

[edit] Tailshaft

Big 1330 uni’s front and rear with a 3.5 inch diameter shaft necked down to take the yokes. Shorter in length to accommodate the extra length of the gearbox. Pink and light green stripe code on shaft.

[edit] Gearbox

Toploader. Long extension housing 31 spline output shaft in a choice of two ratios:

[edit] Standard ratio

  • First gear and reverse - 2.78:1
  • Second - 1.93:1
  • Third - 1.36:1
  • Fourth - 1:1

[edit] Close ratio

  • First gear and reverse - 2.32:1
  • Second - 1.69:1
  • Third - 1.29:1
  • Fourth - 1:1

[edit] Clutch

A modified version of the twin plate clutch was used on the Phase 3. Cylindrical steel adaptor plate drive lugs were used in place of the cast iron lugs. The adaptor plate has been reduced in thickness by 10 thou . The pressure plate is now positively located in relation to the pressure plate cover and diaphragm spring by 3 dowel pins which are riveted to the pressure plate cover.

[edit] Engine

  • The engine was basically a pulled down and reworked 351 4V out of the crate .
  • Shaker was the same as the GT but with 2 mods. The hot air intake snorkel was removed and blanked off and the cold air intake shut off flap was removed so that there was cold air intake all the time.
  • Carby was a 780 Vac Secondary Holley specially made for Ford. Part number on carby horn DOZF 9510 Z. A bakelite spacer was used underneath for the PCV valve connection as there was none on the carb.
  • Intake manifold was standard cast iron dual plane 4V type with 2 modifications. The two front venturis were opened out slightly and the exhaust gas heat exchanger holes were blocked off with grub screws.
  • Distributor was a modified Autolite dual diaphragm, dual advance unit as fitted to the GT and converted to a dual point mechanical advance type.
  • Heads were machined to take screw in studs and 3/8 inch pushrod guide plates. Single groove valves and locks were used in place of the triple grooved ones. Different spring and damper combination was fitted all ready to take the solid stick.
  • Cam was available in 2 types . One with a theoretical lift of .494 inch and the other with .524 inches. Both were solid tappet cams. Both were 40-80/84-36, tappet clearence was 25 thousanths of and inch. Some teams closed this to as tight as 15 thou which gave more power for short races.
  • Water pump had a .750 inch diameter dual ball bearing race assembly fitted to improve load carrying ability and it is less sensitive to bearing bore machining variations.
  • Block had 2 bolt crank caps and not 4 bolt as a lot of people seem to think, as it was just a pulled down 4V, remember.
  • Bottom end was balanced along with the new Boss 351 harmonic balancer . One thou undersized special compound bearings were fitted. Standard capacity sump had one mod. It had a 'crank scraper' type windage tray spot welded at the rear.

According to Howard Marsden, team boss at the time, the race engines where making 330 to 340 bhp. The street cars made 280 to 300, not 380 as many think.

30 GTHOs were called Bathurst specials. They were the QC (Quality control cars). All were bluprinted, all had the high lift cam, and all had lighter bodies.

[edit] Exhaust

Head Mod ( HM) headers were used and these were of a tuned length type through a 2.25 inch exhaust to a special sports muffler at the rear, then 2 inch tailpipes as in the GT. However they were subject to a recall and fitted with extra front resonators in the early stages.

[edit] Radiator

A 14 fin per inch 2 core (not 3 core ) radiator was used as fitted to any 351 optioned car with factory air conditioning. The only difference being that the radiator never had the cooler tube for the auto trans pipes in the lower tank.

[edit] Wheels

Wheels were 14" x 6" five slot JJ safety steel rims. 14" x 6" Sports Road Wheels were an option as in the GT but only 2 HO's had them. In 1972 the dealers sent out a notice to all owners of the Phase 3 that they were offering 15" x 7" Bathurst Globe Mags as an option at a very low cost. This was so that they could race with them at Bathurst.

[edit] Extras

The only thing that was standard on the GTHO that was optional on the GT was the 36 gallon fuel tank. You had to pay extra for the left hand mirror. You had to pay extra for the radio. You had to pay extra for the bumper bar overriders and you had to pay extra for the privilege of owning the greatest race car ever produced by Ford Australia.


Accomplishment Result
0-30 mph 2.3 seconds
0-40 mph 3.3 seconds
0-50 mph 4.8 seconds
0-60 mph 6.4 seconds
0-70 mph 8.3 seconds
0-80 mph 10.4 seconds
0-90 mph 12.4 seconds
0-100 mph 15.2 seconds
0-110 mph 18.5 seconds
0-120 mph 22.5 seconds
0-130 mph 25.6 seconds
0-140 mph 31.4 seconds
Standing 1/4 mile 14.7 seconds @ 97 mph
Top Speed (with 6,150 rpm rev limiter) 141.5 mph
Top Speed (without rev limiter) 155 mph

These figures are sourced from Wheels magazine, [2] October 1971 issue.

[edit] Value

The Phase 3 is in incredibly high demand. Good examples of the Phase 3 sell for in excess of $525,000. [3] Due to this demand, and rarity, there has actually been a flow on effect into values of the lesser XW-XY Falcons, particularly genuine GS and GT models. other models that also benefit from the success of the GTHO include the XA and XB GT hardtops as well as the lesser known Phase 1 and 2 XW GTHO.

A Falcon GT-HO Phase 3 was sold at auction for A$683,650 on Sunday 25th March 2007. The car had just 40,000 km on the clock. The buyer of the car said it will be garaged, and that he won't be driving it; he will be "keeping it as an investment". [4] The sale price set a new auction record for Australian "muscle cars". [5]

On Sunday 3rd June 2007 The Sun-Herald reported the sale of Phase 3 for $750,000. [copy of page 13 of newspaper: [6] ] The writer of this article, Joshua Dowling, refers to the abovementioned previous record set at Bonhams & Goodman and states that, from a production run of 300 vehicles, "experts believe there fewer than 100 remain". The vendor of the Phase 3 was Harry Christian. [7]

[edit] Alternative Names

The name of the car is often abbreviated to 'GT-HO Phase III' or even just 'Phase 3'. Sometimes it is even referred to as a 'Hoey' It was also known as the 'Shaker' because of the shaker scoop that protruded out of the hood and shook as the powerful Cleveland revved.

[edit] Race record

Ford Australia and Allan Moffat had great success with the Phase 3 in the Australian touring car racing where it was piloted to many race wins over its short life. One of the Phase IIIs driven by Moffat is now owned by Bowden's Own, an Australian car care products company.[8]. This example was driven to a number of victories by Moffat, as listed below

  • 1st 1971 Hardie-Ferodo 500, Bathurst
  • 1st 1972 TAA 1 Hour Race, Calder
  • 1st 1972 Australian Manufacturers' Championship, Round 4, Phillip Island
  • 1st 1972 Australian Manufacturers' Championship, Round 5, Surfers Paradise
  • 1st 1973 Australian Touring Car Championship, Round 1, Symonns Plains
  • 1st 1973 Australian Touring Car Championship, Round 2, Calder
  • 1st 1973 Australian Touring Car Championship, Round 3, Sandown Park
  • 1st 1973 Australian Touring Car Championship, Round 4, Wanneroo Park
  • 1st 1973 Australian Touring Car Championship, Round 7, Oran Park

[edit] Successor

In 1972, the XY series Falcon was replaced by the redesigned XA Falcon range. Production of the XA based 1972 Falcon GT-HO Phase 4, which was superior to the Phase 3, commenced in mid-June 1972 but production was stopped due to a "Supercar Scare", e.g. The Sun-Herald ran this as its frontpage lead article (with banner headline in large capital letters) on Sunday 25th June 1972: 160mph 'Super Cars' Soon [a copy of that front page is shown at the start of a Phase 4 documentary here: [9] ].

Four vehicles were built when production was stopped -- three as race cars for the Bathurst 500 in October, and one made it off the production line for sale to the public. The four vehicles were sold by Ford Australia, but the Phase 4 was never officially released. [see "The Final Finest Phase" article in "Super Ford" magazine, 1987, pp. 20-27 [10] ]

[edit] References