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1968 MERCURY Cougar XR7 302-2 bbl/ MPG= 12.3 City/ 17.4 Hwy PDF Print E-mail
Written by Double Dragon
Monday, 10 May 2010 12:12

1968 MERCURY Cougar XR7 302-2 bbl/ MPG= 12.3 City/ 17.4 Hwy


Writing and photography copyright D. S. Brown. Brochure and owner's manual images copyright Mercury.

Metric= 5.0 L engine- 19.1 L/100 km City, 13.5 L/100 km Hwy

In April, 1964 Plymouth released the compact Valiant based sporty fastback Barracuda. A few weeks later Ford released a similar small sporty personal car based on Falcon mechanicals called the Mustang. The overwhelming success of the Mustang eclipsed the Barracuda and all later attempts by competitors to field their own 'ponycar'. In Fall, 1966 the Mercury Cougar joined the ponycar wars as a 1967 model year car at the same time the Chevrolet Camaro debuted. At the start of 1967, the Cougar XR7 option was released and shortly after that came the Pontiac Firebird. The AMC Javelin appeared as a 1968 model.

The Cougar did quite well in its debut year despite so much competition in the 'ponycar' market. Part of the appeal is attributed to the different direction Mercury took with the Cougar. Instead of duplicating the Mustang, the Cougar reworked the Mustang chassis with a unique body that combined some 'mini Thunderbird' luxury cues and added details reminiscent of the Jaguar. Economy was not mentioned. Unlike the Mustang no six cylinder engine was available in the Cougar. The Cougar had 3 extra inches of wheelbase and more soundproofing which created a softer smoother ride. Although it had power with a standard 289, raciness was originally downplayed in favor of refinement. The Mercury promotion people didn't want to equate the Cougar with the rest of the crass hot dog stand cruising weekend drag strip machines pumped out to fight the musclecar wars. The XR7 package took the 'European' concept further by openly mimicking the Jaguar with similar faced 'rally' gauges, wood dash and toggle switches, and real leather bucket seats.

Mercury and Pontiac both occupied the same spot in the hierarchy of their respective mother corporations. Pontiac was one price step above Chevrolet just as Mercury was a price step above Ford. Both divisions disguised the common chassis structures used for their vehicles quite artfully and both divisions became enamored with infusing their product lines with a European flavor.

Over at Pontiac European names had been lifted for romping snorting musclecars such as the GTO and Grand Prix but aside from using Liters to designate engine sizes, the engineering was traditional. When Pontiac division manager John DeLorean pushed for radical engineering, the public didn't buy it. He had a front engine Tempest using a 'rope drive' flexible driveshaft powering a rear differential/ transmission combo hooked up to independent rear suspension. DeLorean then campaigned to get an overhead cam Sprint Six LeMans built. Pontiac sent a four speed manual OHC Sprint Six to Europe to test it on the winding open roads. Sadly, the terrific Sprint Six never caught on with buyers.

However, over at Mercury the European angle worked just fine. The less exotic mechanicals in the Cougar allowed it to capture 100,000 sales in its first year. Success came by basing the looks on 'European domestic' styling rather than engineering. Mercury pushed the European sporty angle pretty hard. They paid to have retired Indy champion Rodger Ward flown out to Las Vegas, Nevada to compare an iron block pushrod 427 four speed Cougar XR7 to an Aston Martin DB-6 with an aluminum block, OHC and three Webbers and five speed. The story in POPULAR MECHANICS March 1967 actually put the two cars on a race track to compare lap times. Of course the DB-6 trounced the Mercury on the race course, but not by much. Acceleration trials showed the Mercury leaving the DB-6 in the dust.

The success of the 1967 Cougar allowed Mercury to carry over the same car for the 1968 model year. New safety standards mandated the addition of side marker lights and a padded steering wheel. Emission controls hit everyone in 1968. The Ford 302 is a stroked 289 intended to eventually phase out the 289 because stroked engines burn cleaner. The extra cubes also assist in compensating for the drop in engine efficiency caused by the emissions equipment.

The Big Three stroked many of their engines for the 1968 model year. Chevy came out with a stroked 307 version of the 283 this year; Pontiac took their 230 six cylinder up to 250, Olds enlarged the 330 to 350 and Buick jumped from 340 to 350. A few years later Chrysler took the 383 up to 400 for the same reasons. Originally all 1968 Cougars were intended to receive the 302 as the standard engine, but the policy changed early in the production year. Standard Cougars were equipped with the same 289 as in 1967, while XR7s and Decor Group cars jumped up to the 302 for base equipment.

The fuel mileage of the 1967 Cougar was acceptable for a 'personal luxury car' which is where it fit into the hierarchy of models. Unlike a Thunderbird with a 390, a base 289 Cougar was capable of mileage figures nearly as decent as the lighter nimbler Mustang 289. Emissions equipment for 1968 combined with the larger displacement dropped MPG from 1967 levels.

The OOCC Cougar XR7 matches the MPG figures of 1968 Cougars back when they were new. The OOCC XR7 experienced less than optimal driving conditions as compared to conditions back in 1968. Modern technology seems to have made up the difference.

The OOCC Cougar XR7 City MPG figures were recorded in cold weather below National averages in winter. Magazine MPG figures back in 1968 derived from tests made in warmer weather. The huge California population infuses a large proportion of warm weather condition mileage figures into the POPULAR MECHANICS 'Owner Reports'. The overall MPG reported will be slightly skewed towards warm weather conditions. Modern city gridlock is more prevalent now than in 1968.

The potential mileage advantages the original Cougars held back in 1968 are offset by several technological advancements available to the OOCC Cougar in the 1990s. The OOCC Cougar engine was broken in whereas a portion of the POPULAR MECHANICS owner's reports in 1968 would be recorded using a tight new engine. In the 1960s it took 1,000 to 2,000 miles for break-in of an engine to be completed sufficiently to achieve optimum MPG.

Superior modern energy efficient oils and radial tires create higher MPG opportunities for the OOCC Cougar. The OOCC Cougar XR7 has non factory dual exhaust which enhances MPG compared to the stock single exhaust system, particularly at higher engine RPMs. Conversely, the OOCC Cougar XR7 has a performance camshaft with extra overlap which is notorious for poor low speed MPG.

The OOCC XR7 had some extra advantages when racking up figures for its Highway MPG. Most of the driving was in warm areas which improves MPG. Despite similar weather to the original tests, plus advantages such as superior Interstates and energy efficient oils and tires there is no improvement in highway MPG. This is possibly explained by high cruising speeds. In the 1960s average cruise ranged between 55 to 70 MPH. Modern traffic flows at 70- 80 MPH. Although the majority of the gas logs reflect primarily 65- 70 MPH cruising, some of the highway cruising was logged in desert areas between 90 and 100 MPH and some late night deserted highway runs were made over several miles at 110- 115 MPH which quickly ate up the margin.



The Pure Oil tests printed in POPULAR MECHANICS April 1968 precisely measure the gas mileage obtainable over a fixed course. The cars use exactly one gallon of cold gasoline kept on ice to approximate the temperature of gas pumped out of an underground gas station storage tank. Although varying speeds are used, the car has to maintain an overall average speed of 40 MPH.

The cars are tested during winter with alternating years in sunny Daytona, Florida and Riverside, California. The 1968 tests were held in Riverside where January daytime temperature peaks around 66 Degrees F (19 degrees C).

A new 1968 Cougar 302 2 barrel with automatic transmission produced 19.3 MPG on the Pure Oil closed course. Pure Oil cars are stock. The Pure Oil Cougar would be shod with stock E70x14 tires and a 3.00:1 axle. The Pure Oil figure is approximately 6% better than regular Highway MPG.

The 6% adjustment derives from a side by side comparison of Pure Oil results to the POPULAR MECHANICS Owner Reports for the same year and model of car. A 1968 Firebird in the Pure Oil tests turned in 16.7 MPG using a 350 2 barrel automatic. Owner's Reports cited 12.3 City MPG and 15.7 Hwy MPG for 1968 350 Firebirds that the majority of respondents drove.

Owner's Reports Highway MPG is 94% of the Pure Oil figure. Applying this ratio to the Pure Oil 1968 Cougar 19.3 figure converts to about 18 MPG in regular highway driving conditions.

The July 1968 CAR LIFE road test of two Cougars compared a 302 with a 427. The 302 4 barrel automatic Cougar had dual exhaust and a 3.00:1 axle. The Cougar's full load of options resulted in a curb weight of 3,385 pounds. It was riding on F70x14 Wide Ovals set at 25 PSI. Car Life managed 12.8 MPG in their test driving. CL figured the 302 would give 12-16 MPG under normal conditions.

The 1968 Cougar owner's manual shown below indicates that 289, 302 and 390 cars were only supposed to receive the E70x14 tires, not the F70s. Often factories equipped their test cars a little to a lot better than standard issue calls for. The original window sticker for the OOCC Cougar listed E70x14 Wide Oval tires.

68 cougar owners manual pg 47 tires

The shipping weight for a standard Cougar is 3,094 pounds. The XR7 shipping weight is 3,134 pounds. The curb weight for the two models works out to 3,230 pounds and 3,270 pounds. The NOV 1967 issue of POPULAR SCIENCE quotes the base Cougar curb weight at 3,240 pounds. If their figure is correct this would likely inflate the XR7 model 10 pounds, too.

The CAR LIFE Cougar exceeds the weight of the OOCC Cougar. The CL Cougar was a standard Cougar 302 with dual exhaust. The lack of XR7 package weight is cancelled out by the CL Cougar having A/C which weighs more than the XR7 package. The OOCC 302 dual exhaust Cougar doesn't have A/C, but does have the XR7 package. If we take the corrected PURE OIL 302 test figure of 18 Highway miles and average it with the CAR LIFE 302 estimate of 16 we get 17 MPG Highway. CAR LIFE estimated 12 MPG City for the 302.

CAR LIFE got significantly lower mileage out of their test Cougar with 427, automatic, 3.50:1 axle and the F70 tires. The Cougar with bigger 427 weighed in at 3,662 pounds curb and managed 10.2 MPG on the test driving. CAR LIFE expected it would return 10-14 MPG under normal conditions.


OOCC Cougar XR7 CITY MPG= 12.3

The OOCC Cougar XR7 has few options other than the terrific XR7 option package. The OOCC Cougar has Non -emission system engine, E70x14 Wide Oval Tires, power steering, AM radio, automatic transmission, rear defroster (in contradiction to the bulletin below which states it was not available), door edge guards and console. Like many 1960s cars it was ordered with manual drum brakes. The 302 engine is one step up from the base 289, but all 1968 XR7s automatically bumped up to the 302 as mentioned in this supplement to the showroom brochure reproduced below.


The OOCC Cougar XR7 was ordered March 18, 1968 and built three days ahead of schedule on Tuesday March 26, 1968 in Dearborn, Michigan. The MARTI REPORT reveals true build date while the door tag code 'C29' indicates scheduled build date.

The VIN decodes as follows (significant digits are not shown to protect owner privacy)

8= 1968
F= Dearborn, Michigan final assembly
93= Cougar XR7 Hardtop
F= 302-2 barrel engine

The door tag provides additional information.

65B= Cougar XR7 hardtop
B= Dark Cherry paint
6D= Dark red leather bucket seats
29C= Scheduled build date March 29, 1968 (actual date was March 26)
A7= Pacific Canada Ordering District
5= 3.00:1 Standard axle ratio
W= C4 Merc-O-Matic transmission

The OOCC Cougar is purportedly a one owner car driven from purchase date May 7, 1968 until the beginning of the 1990s when it was showing 113,000 miles. The driver's door arm rest was recovered; the leather seats were worn and crinkled but not split or ripped. There were no cracks in the steering wheel and no major wear on the pedals. The car sat virtually unused for several years. The original owner drove about 3,000 miles during the 1990s before he passed away. The car was inherited by the grandson who sold it without having ever licensed it showing 116,000 miles on the odometer.

The Cougar needed battery, belts, hoses, brakes, tires, a new passenger floor, frame rails, torque boxes and shock towers. A hole in the trunk also required a patch. Interestingly, the entire floor was good except for a 6 inch portion running along the passenger side where most road salt accumulates. This usually happens with cars that aren't washed frequently. It's also possible the car was habitually parked with one side unprotected in an unenclosed car port. 1960s Fords are particularly susceptible to rust, so it wouldn't have taken too much to create this problem.

The original owner dealt with body rust during his repaint of the car (using correct factory code paint) by having small plates welded into the front inner fender areas. His notes in the owner's manual underline the part numbers of transmission fluid and power steering fluid (identical). He also jotted down the conversion of quarts to liters in the engine oil page which suggests he may have done some maintenance on the car himself. A craftsman used dyed leather to recover the driver's door pull and perhaps this was the original owner's handiwork.

The original air cleaner assembly, master cylinder, steering box, springs, alternator, radiator, starter, water pump and fuel pump are still in place. The original owner rebuilt the engine including a performance cam, true dual exhaust with low back pressure performance mufflers and a complete carburetor rebuild. The engine rebuild was likely necessitated by boat towing. The Cougar had a trailer hitch which was later removed.

The OOCC Cougar XR7 engine  has a nice rumble and noticeably non-stock lumpy idle. It runs very strongly and trouble free while posting very low emission levels when tested. This is in contrast to the July 1968 CAR LIFE Cougar 302 which annoyed testers. The trouble was associated with a very high idle, necessary to overcome emissions drivability issues. The owner's manual calls for 500 RPM for Canadian non emission control 302 automatics versus 550 for USA emission control engines. The manual shift Cougar 302s jump from 525 RPM idle speed on Canadian cars to 625 RPM for USA engines.

The Canada spec OOCC Cougar XR7 was a "Non emission System" engine because of the loophole opened for cars being exported out of USA. This undoubtedly contributed to the excellent starting and running in all sorts of weather conditions. The owner's manual provides separate point gaps, dwell angles and idle speeds for USA Cougars (with exhaust emission controls) and Canadian Cougars (non exhaust emission controls).

Despite the obvious cam change, there seems to be enough vacuum because the hidden headlight doors opened and closed properly. The OOCC three speed C-4 Merc-O-Matic transmission is original to the car as is the 3.00:1 rear axle.

The overall condition under hood and interior support the available records showing that the car had travelled 116,000 miles. The front dash firewall area leaked until repaired with a readymade cowl package for Mustangs and Cougars. The rear sequential turn signal mechanism seized up due to moisture buildup in the trunk. After two expensive overhauls, the system was bypassed with an aftermarket solid state system. Other electrical gremlins plagued the Cougar such as a faulty marker light ground, fuel, oil pressure, volt and temperature gauge failures. See the story on the ONE OWNER 1973 Cougar XR7 which had light flickering issues and electrical hassles right off the dealer's lot and gauge sending unit failures in its 9th year of life.

Once the OOCC Cougar was put back in service the new chemicals present in modern gasoline didn't agree with the old spec fuel hose which became brittle and leaky. A garage using the method of 'diagnosis through parts application' mistakenly replaced the fuel pump when the actual failure was due to a degraded fuel hose.

The OOCC Cougar XR7 runs Michelin radial P205R70s pumped up at 35 PSI. These modern radials replaced the stock bias ply E70x14s and are equal in section width and diameter within fractions of the originals. The original tires called for 24 PSI front and rear inflation pressures. The new tires with higher inflation reduce rolling resistance and improve MPG. See the article on tires in this GAS LOG section for more information on bias ply vs. radial tires and format changes in section height.

The 1968 Cougar XR7 has a shipping weight of 3,134 pounds. This figure is likely inaccurate, because manufacturers lowball this number to reduce shipping charges on the millions of cars they move every year. Theoretically this is the weight of the base car without any options, all fluids in place and a token amount of gasoline in the tank.

Filling the 17 gallon tank would yield the curb weight. Adding 15 gallons to fill the tank (91.5 pounds using 6.1 pounds per gallon) brings weight up to 3,225 pounds curb weight if the XR7 shipping weight was correct.

It all gets hazy anyways, because most of the XR7s out there were loaded with typical options such as automatic transmission, power steering, power disc brakes, radio and often A/C.

The OOCC Cougar doesn't have A/C, nor power brakes, or disc brakes. The heaviest option it has is the XR7 package which adds over 100 pounds above the standard Cougar. All summed up, the Cougar XR7 is a reasonably sized fairly light car which was reflected in the decent MPG figures on the highway.

The gas logs for the OOCC Cougar XR7 are below. The amount of gas in gallons is listed to the right of the odometer mileage figure. Most of the entries are complete fill-ups. The reference to 'lead sub' lists the quantity and approximate mileage that lead substitute was purchased. Portions of the 250 ML bottles of lead substitute additive were dumped into the tank with each gas fill. The total number of bottles added was 4.75 L= 1.23 US gallons.

The gasoline at this time was laced with up to 10% ethanol as is the case with most modern gasoline. The ethanol reduces the total energy potential in the gasoline reducing MPG figures. Chevron 94 octane gas which is ethanol free is used for the majority of fill-ups. The original owner's manual calls for 94 octane.

The total of 7,042m miles of CITY DRIVING required 547.9 gallons of gasoline, plus 1.2 gallons of lead substitute. Not counting the first fill-up leaves 541.40 Gallons, plus 1.2 lead substitutes to drive that distance.

There are three entries in the city miles list that are excluded from the overall calculations: entries at 27,240 miles, 27,399 and 27,559 were fill-ups during a highway trip. The mileages following these fills are left out of the final reckoning because they were highway miles.

The city MPG equals 13.0 mpg not counting the lead substitute and highway driving.

The real distance driven is less than indicated. Comparing the odometer to highway mileage markers reveals an exaggeration of 1/10th of a mile for every 2 miles travelled. The odometer reading is high by 5% which typical of 1960s cars. True City MPG works out to 12.35 MPG when the 5% error is corrected.

Odometer Gallons Octane (lead)   Full Tank?  MPG (uncorrected)

16,837       2.6   (Chevron 94)      X              N.A.
16,837       1.9   (Mohawk 94)       Full Tank   N.A.   
16,937       7.9   (Mohawk 94)       Full Tank   12.7 MPG 
17,045       9.5   (Mohawk 94)       Full Tank   11.4 MPG
17,156      10.1  (Mohawk 94)       Full Tank   10.9 MPG
***Missing entries***
17,586       8.8   (Mohawk 94)       Full Tank   N.A.
17,724       9.8   (Chevron 94)       Full Tank   14.1 MPG
17,000   lead sub= 500 ML
17,859      10.7                           Full Tank   12.6 MPG
18,011      10.3   (Chevron)           Full Tank   14.8 MPG
18,000   lead sub= 1,500 ML

(*18,000 miles to 24,000 miles is covered below in HWY miles table*)

Odometer Gallons Octane (lead)   Full Tank?  MPG (uncorrected)
20,500    lead sub= 500 ML
23,918        6.3   (Chevron 92)     Full Tank   (see HWY miles)
24,024        9.1   (Chevron 92)     Full Tank   11.6 MPG
24,104        7.1   (Chevron 92)     Full Tank   11.3 MPG
24,205        8.4   (Chevron 92)     Full Tank   12.0 MPG
24,340       11.9  (Chevron 92)     Full Tank   11.3 MPG
24,448        8.7   (Chevron 94)     Full Tank?
24,530        7.2   (Chevron 94)     Full Tank   11.9 MPG
24,700        7.0 gal
24,727       10.1   (Chevron 94)     Full Tank
24,000    lead sub= 1,000 ML
24,828        7.5 gal
24,949       10.3 gal
25,038        6.9 gal
25,147        7.8 gal
25,236        4.9 gal
25,236        4.0 gal
25,347        8.8 gal
25,421        5.4   (Chevron 94)    Full Tank
25,519        7.6   (Chevron 94)    Full Tank   12.9 MPG
25,622    lead sub= 500 ML
25,622       10.0   (Mohawk 87)    Full Tank   10.3 MPG
25,723        7.1    (Exxon 94)       Full Tank   14.2 MPG
25,820        4.9 gal
25,938        8.3 gal
26,000    lead sub= 750 ML
26,028        7.2   (Mohawk 92)    Full Tank   12.5 MPG
26,131        8.7   (Chevron)
26,246        8.6   (Superstore)
26,392        9.5   (Chevron 94)    Full Tank?
26,506        8.3   (Chevron 94)    Full Tank
26,605        8.6
26,684       10.8   (Chevron 94)    Full Tank
26,758       12.4   (Chevron 94)
26,822        4.9   (Chevron 94)
26,867        5.2                          Full Tank  
26,922        6.7                          Full Tank    8.2 MPG 
27,055       10.7                         Full Tank    12.4 MPG
27,121        5.4                          Full Tank    12.2 MPG 
27,240        8.7   (92 octane)        Full Tank    13.7 MPG
27,399        8.1   (92 octane)        Full Tank    19.6 MPG (*Highway driving*)
27,559        8.5   (92 octane)        Full Tank    18.8 MPG (*Highway driving*) 
27,678        4.6   (Chevron 94)      Full Tank    25.8 MPG (*Highway driving*)
27,830       13.4  (Chevron 94)       Full Tank   11.3 MPG
27,950        7.5   (Chevron 94)       X   
28,076       14.3 gal
28,192        3.6 gal
28,243        6.8   (Chevron 94)     Full Tank
28,312        8.5   (Chevron 94)     Full Tank   8.1 MPG
28,448        3.8   (Chevron 94)      X
28,501        9.4   (Chevron 94)     Full Tank   14.3 MPG
28,639        3.5   (Chevron 94)     X
28,684       10.8 gal
28,801        4.4   (Chevron 92)     X
28,853       10.1 gal
28,972        7.5 gal
29,077       11.9 gal
29,185        7.5 gal
29,296        8.9 gal
29.381        5.6 gal
29,000        7.5 gal
29,580        8.9   (Chevron 92)    Full Tank
29,680        9.2 gal
29,781        9.7 gal
29,881        8.3 gal
29,994        9.9 gal
30,107        8.8 gal
30,168        6.5 gal

The OOCC Cougar XR7 had a full tank most of the time, mainly 92 or 94 Octane Chevron. Occasionally Mohawk, Exxon or Superstore brand gas was used. Lead additive was put into the tank at each fill-up. Aside from the driver, additions to the curb weight were minimal: occasional passengers, and heavy items about a quarter of the time. Averaging out the various weights in the car equals an overall average payload of about 250 pounds.


As attested in the above interior shot, the OOCC XR7 was subject to cold, wet weather. It was parked outdoors at all times making cold starts in weather averaging 2 Degrees C (35 degrees F). The XR7 was used daily for a 4 mile round trip and saw a lot of cruising around. It was driven quite fast and hard at times.



This gas log covers a road trip over thousands of highway miles on Interstates and secondary highways in Canada, USA and Mexico. Unless noted (for instance, 10 MPH and 30 MPH in a mountain snowstorm) Interstate average speed was 70 MPH with some stretches of 90 or 100 MPH. A large portion of the trip was made on secondary highways at an average of 60 to 65 MPH.

The factory tachometer provided the following RPM readings at the indicated speeds on the uncorrected speedometer. The figures were noted at a steady cruise in warm temperatures on a flat smooth highway.

35 MPH =  1,400 RPM
40 MPH =  1,600 RPM
45 MPH =  1,750 RPM
50 MPH =  2,000 RPM
55 MPH =  2,250 RPM
60 MPH =  2,400 RPM
65 MPH =  2,650 RPM
70 MPH =  2,800 RPM
75 MPH =  3,050 RPM
80 MPH =  3,300 RPM

Although not recorded in the notebook, the driver recalls that just shy of 100 MPH the car is winding around 4,000 RPM. Compare these RPM results with the modern cars in the GAS LOGS such as the 1992 Toyota Camry, 2003 Ford Mustang or 2005 BMW 325xi. Modern overdrive reduces engine speed dramatically as compared to the direct 1:1 top gear found in 1960s cars.

Fill-ups consist mainly of 92 Octane Chevron with some lead additive poured in at each fill-up. Mobil and Exxon were also used occasionally. Oil varied from 10W30 to 10W40 generic house brands of various garages used along the way. The tires were inflated to 35 PSI. The weather averaged 60 to 80 degrees F (15 to 27 degrees C) most of the time, except for the previously noted mountain snowstorm.

There were occasional passengers in the car, but the majority of time the XR7 carried one driver, luggage, food and water totaling 450 pounds, usually running full tanks of gas. The gas tank holds 17 gallons which weighs about 6 pounds a gallon. A full tank is 100 pounds. Windows were closed, with vent windows fully open, radio on most of the time, running lights about half the miles.

First line is the mileage from odometer, second figure is number of gallons of gas, third is the octane and brand of gas if noted, fourth column notes a full tank. If tank wasn't filled, no MPG figure can be calculated and this is indicated as 'X'. The last figure of MPG is based on the odometer reading of the Cougar which as discussed before is off by 5%.

The OOCC Cougar XR7 used 314.9 gallons to go 5,723 miles. Correcting for the 5% fast odometer, we need to remove 286 miles from the total. The actual miles are 5,437 plus 60 miles that are not accounted for in the tables equaling a trip of 5,497 miles producing 17.4 MPG HWY. There are fill-ups that range as high as 22-23 MPG but they are offset by figures in the lower teens.

Odometer  Gallons  Octane       Full Tank?   MPG (uncorrected)

18,133       12.6   (Chevron 94)   Full Tank    (city driving- see table above)
18,195        5.2    (Chevron 92)   Full Tank    11.9 MPG
18,341        8.4    (92 octane)     Full Tank    17.3 MPG
18,477        6.8    (Chevron 89)   Full Tank    20.0 MPG
18,648       11.4   (Chevron 92)    Full Tank    15.0 MPG
18,810         0.0       -              (Mountain snowstorm= 10 MPH)
18,825       10.5    (92 octane)    Full Tank    16.8 MPG
18,898         0.0       -               (Snowstorm & ice warning= 30 MPH) 
19,002        8.5     (Chevron)      Full Tank    20.8 MPG
19,148        9.7     (92 octane)    Full Tank    15.0 MPG
19,148        0.0        -               (Heavy traffic stop and go driving)
19,246        7.8                         Full Tank    14.8 MPG
19,452      10.0      (Chevron 92)  Full Tank    18.8 MPG
19,581        6.9      (Chevron 92)  Full Tank    18.6 MPG
19,694        6.7      (Chevron 92)  Full Tank    16.8 MPG
19,871        5.0                          X
19,931        8.0                         Full Tank    18.2 MPG
20,100        9.7                         Full Tank    17.4 MPG
20,173        3.2                         Full Tank    22.8 MPG
20,358        4.9       (Mobil )        X
20,408        2.2       (Chevron)     X
20,566        1.0       (AAA gas)     X- was empty
20,571        4.9       (Chevron)     X
20,583       11.8       (Exxon)       Full Tank
20,700        7.4       (Exxon)        Full Tank
20,864        8.1       (Chevron)     Full Tank    20.2 MPG
21,034        9.5       (Chevron)     Full Tank    17.8 MPG
21,186        6.2                         Full Tank    24.5 MPG
21,299        6.6                         Full Tank    16.9 MPG
21,432        7.1                         Full Tank    18.7 MPG
21,592        8.0                         Full Tank    20.0 MPG
21,640        2.8                         Full Tank    17.1 MPG
21,708        3.7                         Full Tank    18.3 MPG
21,859        6.8                         Full Tank    22.2 MPG
21,973        5.5                         Full Tank    20.7 MPG
22,142        2.5                          X
22,163        7.7                         Full Tank    18.6 MPG
22,288        7.4                         Full Tank    16.8 MPG
22,421        5.9                         Full Tank    22.5 MPG
22,572        4.3                         X
22,608        4.8                        Full Tank    19.5 MPG
22,690        4.8                        Full Tank    17.0 MPG
22,809        4.8                        Full Tank    23.7 MPG
22,918        8.2                        Full Tank    13.9 MPG
23,072        7.1                        Full Tank    21.6 MPG
23,225        8.6                        Full Tank    17.7 MPG
23,351        6.6 (approx)
23,482        6.5 
23,629        8.1                        Full Tank    17.7 MPG
23,774        7.2                        Full Tank    20.1 MPG
23,918        6.3                        Full Tank    23.2 MPG

The calculations above are comparable to the calculations in the other GAS LOGS stories where mileage is rounded off the nearest mile and amount of gas is rounded off to a tenth. It is possible in this story to give a more accurate figure for the Cougar XR7. Prior to departure for the trip the newly fixed gas gauge broke again. This prompted the driver to precisely track MPG in order to ascertain the car's highway range. The tank was filled up before 200 miles registered on the trip odometer. During city driving only 100 miles were allowed to accumulate on the trip odometer before gas was added.

The tedious record keeping required on the trip to prevent the car from running out of gas is a boon to readers of the GAS LOGS now. The driver created highly accurate logs to determine his mileage which gives us a good account of what that Cougar was capable of.

Despite following the system outlined above the driver managed to run it out of gas anyways! Exceptionally high speeds made possible during late night driving on virtually deserted freeways resulted in significantly higher gas consumption. At 2 AM the engine conked out while flying along at 110 MPH. Lesson learned: the Cougar uses a LOT of gas at higher speeds!

The driver reset the trip odometer readings with each fill. Below are his notes taken to the tenth of a mile with gas fill-ups recorded to two decimal places. When more accuracy is introduced, the MPG figure drops a bit. For comparison purposes this table is 'too accurate' to compare against the final results in other GAS LOGS stories which use a looser set of data to start with.

Miles     Gallons    Full?   MPG

122.2     12.60     Full    09.70 MPG (City driving)
061.3      05.23    Full    11.72 MPG
145.7      08.44    Full    17.26 MPG
136.2      06.85    Full    19.88 MPG
171.0      11.45    Full    14.93 MPG
175.2      10.50    Full    16.69 MPG
177.2      08.52    Full    20.80 MPG 
145.8      09.73    Full    14.98 MPG
115.6      07.80    Full    14.82 MPG
187.4      10.03    Full    18.68 MPG
129.9      06.91    Full    18.80 MPG
112.4      06.70    Full    16.78 MPG
176.9      05.07    X
059.6      08.01    Full    18.08 MPG
165.5      09.73    Full    17.01 MPG
072.0      03.26    Full    22.09 MPG
185.8      04.90    X
049.5      02.28    X
158.5      01.00    X
004.7      04.96    X

68 cougar owners manual pg 48 engines




















Dearborn noon

SU 6 AR- MO 10 PIS- ME 12 PIS- VE 13 PIS- MA 29 AR- JU 26 LE- SA 14 AR- UR 26 VI- NE 26 SC- PL 21 VI- NN 18 AR/

ME 0 VE/ ME 30 SA/ ME 45 MA/ VE 45 MA/ VE 30 SA/ MA tr JU/ MA incj UR/ MA incj NE/ MA biq PL/ JU 30 UR/ JU 90 NE/ UR sx NE

Last Updated ( Saturday, 01 August 2020 21:26 )