Home Travel Stories Gas Logs 1972 BUICK Skylark 350-2 bbl MPG= 11.5 Overall
1972 BUICK Skylark 350-2 bbl MPG= 11.5 Overall PDF Print E-mail
Written by Double Dragon
Monday, 27 December 2010 17:20

1972 BUICK Skylark 350-2 bbl MPG= 11.5 Overall Average


Writing and photography copyright D. S. Brown except for Owner's Manual pages copyright Buick, spec pages copyright World Cars 1972.


Metric= 5.7 L engine- 20.5 L/100km overall average.

The Buick Special debuted for the 1961 model year as a compact car based on the Corvair 'A body' platform. General Motors attacked the foreign compact car market with the Corvair and responded to the unconventional technology used in the imports with revolutionary engineering for a domestic vehicle such as air cooled rear engine, and independent suspension.

Over at Ford, the conventional engineering and pedestrian styling of the Falcon made them the sales winner in the domestic compact market. The Plymouth Valiant was weird looking although it benefited from some terrific engineering most notably the long runners made possible on the slant 6 engine simply by tilting the angle of the cylinder banks.

Rather than follow Ford's example, GM stayed the course of the other domestic compacts and offered cutting edge and often unusual technology when they broadened the use of the Corvair's 'A body' and allowed 'B-0-P' (Buick-Oldsmobile-Pontiac) to have a stab at the market.

Pontiac went totally wild with a 389 V8 sawed in half to create an inline 4 cylinder engine using a rope drive to turn a rear mounted transaxle in their Tempest. Oldsmobile wasn't far behind with an aluminum engine and turbocharging for the F-85. Buick came out with a really sweet engine destined to become the heart of the Grand National musclecars a few decades later but that is getting ahead of the story. In the early 1960s all the 6 cylinder domestic engines were inline engines. Buick managed to create a V6 for their Special that magazine testers of the day proclaimed to be nearly as smooth and powerful as a V8 while offering terrific economy of operation (cheaper tune ups and better MPG).

Each of the compacts soon added a flashy 2 door hardtop bucket seat version. The Skylark was the bucket seat version of the Special. 1963 was the last year of the truly compact Buick Special. In 1964 all of the 'A bodies' jumped from a 112 inch wheelbase to 115 inches with significantly longer overhang which bumped the cars into the 'intermediate' class. All GM divisions reverted to conventional engineering after seeing Ford's sales results with the unsophisticated Falcon.

The basic A body stayed the course with some 'coke bottle' styling additions created for 1966-67. In 1968 the intermediate A body cars were redesigned with sweeping fastbacks and 'ponycar' dimensions. The front hoods were longer and the rear trunk was truncated. Intermediate 2 door A bodies rode a shortened 112 inch wheelbase while the 4 doors used a 116 inch wheelbase. The final year for this racy looking body was 1972.

This OOCC 1972 Skylark was a one owner car originally ordered for highway cruising. This Skylark was setup similarly to a 1967 Cutlass Supreme Turnpike Cruiser but without the big block engine. To see a story on the Turnpike Cruiser check the 1967 GAS LOGS on this site. The OOCC Skylark combines heavy duty suspension for high speed stability with the extremely low highway friendly 2.56 axle which is similar to the Turnpike Cruiser's approach. The car was built Friday Jan 21, 1972 in Flint, Michigan and driven for 11 years by the original owner. He sold it coincidentally on his 59th birthday.

The OOCC Skylark bench seat interior is plush and stylish like all Buicks. The original owner ordered a color keyed garbage can for the transmission hump, with the obvious intention of uninterrupted driving. No one wants to stop to throw out garbage. Because of the luxurious Buick interior, it isn't immediately evident that this Skylark is a bare bones car. Non power four wheel drum brakes, no A/C, no cruise control or power windows. The Skylark does have power steering, a heater/ defroster and a radio, but that's about it.

The optional body side and front fender trim molding, full wheel covers, whitewall tires and a vinyl top enhance the looks of the car. Ever practical, the original owner specified front and rear bumper impact pads.

Under the hood everything is original and very clean. The OOCC Skylark has a factory installed block heater. The odometer was purportedly on its first time round at an indicated 96,000 miles and its possible this is true mileage. The OOCC Skylark was well cared for, miraculously escaping rust which is ubiquitous in the salt belt. The pristine Skylark was driven year round and came with two bias ply snow tires in the trunk. The original wheels had early 1970s era bias ply whitewall tires mounted with original hubcaps. The tires were old but the sidewall stripes were kept pure white by the original owner.

72skylark- owner manual pg 58

The tires were set to 32 PSI which is the maximum inflation for the G78-14 bias ply tires according to the Skylark owner's manual. The original format bias ply tires reduce potential MPG because of their inherent higher rolling resistance compared to radials which have less 'tread squirm'. See the article about bias ply versus radials in the GAS LOGS introductory articles.

72 skylark owners 59 tires



1972 BUICK Skylark 350-2 BBL MPG WHEN NEW

POPULAR MECHANICS July 1972 issue ran an Owners Report on the 1972 Skylark 350. The owners reported almost identical city MPG to the OOCC Skylark. The PM average MPG from 963,353 miles of driving came to 11.9 MPG CITY and 14.5 MPG HWY. There were many complaints about the mileage. Former owners of 1960s Skylarks were annoyed by the drop in efficiency due to lower compression ratio and addition of emission controls.

When this sleek new Buick Special/ Skylark bodystyle first appeared for the 1968 model year the car was indeed posting better MPG figures. POPULAR MECHANICS April 1968 ran an owner's report on a 1968 Special Deluxe equipped with the 350 which provides a direct comparison to the 1972 Skylark with 350. The 1968 Buick Special owners reported 13.2 MPG City and 16.2 MPG on the highway. Bear in mind that 1968 was the first year for emissions controls so engine efficiency was already compromised when compared to a 1967 Buick.

WORLD CARS 1972 reported better gas mileage. In the preface the Editor explains that the MPG figures are 'approximate' calculated for "a medium load at a cruising speed of about 60% of the cars maximum speed on a varied run." WORLD CARS 1972 estimated top speed at 96 MPH which means they calculated gas consumption at a cruise speed of 57 MPH delivering 16.6 MPG.

72 skkylark world-cars-1

The WORLD CARS statistics for the more powerful engines below demonstrate that even the 455 was supposedly incapable of much top end speed. GM supplied the data at a period when manufacturers were seriously downplaying the potential of their cars. With the insurance rates gong sky high and safety hearings denouncing them, domestic car manufacturers distanced themselves from the horsepower wars of the muscle car era. WC claims a maximum speed of only 114 MPH for the top dog 455 which was one of the last remaining muscle car engines available in 1972 from any manufacturer. Even with a numerically high axle ratio the engine had enough power to push it faster than that. The 455 was right up there with the Hemi during the last phase of the super car era.

The figures in the WORLD BOOK are all calculated rough estimates at best, so the MPG numbers are probably no more accurate than top speed listings. In the photo below note that WORLD CARS identifies a four door Skylark Custom in a photo as a two door. In fairness to the editors, you have to expect mistakes and oversights on a project as ambitious as this. They are trying to coordinate all the information on every car in the world.




City MPG is typical of an A body GM car from this era. The engine ran silky smooth and quietly with reasonable power, didn't use a single drop of oil, but got abysmal gas mileage. The carburetor acted up in cold weather, with occasional stalling. It's easy to blame everything on a maladjusted carburetor; however, several tune-ups and adjustments revealed that the carburetor and tune was at factory spec. The low miles well documented 1972 Luxury LeMans also profiled in the GAS LOGS section of this site was similarly plagued with stalling and cold running problems right off the factory line. GM just couldn't get add-on emission equipment to harmonize with engines originally designed without those devices in mind.

The Owners Report in POPULAR MECHANICS complained about stalling in cold weather when the 1972 Buick Skylarks were brand new. The emissions related setup meant the fuel mixtures were set very lean which causes problems in minus 20 degree weather. Lack of vacuum advance in lower gears and a high idle caused other problems for owners when the Skylark was first released back in 1972.

The OOCC Skylark's mileage was recorded in sub zero degrees F (-10 or less C degrees) and snowy conditions. The majority of the driving was a work round trip of 18 miles. There were few opportunities to exceed 65 MPH on the work route which used a heavily traveled highway to and from. Mixed into this log are occasional 10 mile runs on deserted secondary roads at a steady 90 to 100 MPH. There were also regular stop and go runs on city streets.

The Skylark curb weight is 3,651 pounds. World Cars book quotes 3,729 pounds, but we'll stick with the AMA specs.

Automatic transmission adds 29 pounds

AM radio adds 7 pounds

Power steering adds 29 pounds

Heavy duty suspension, block heater and garbage can probably add another 15 pounds

The total is approximately 3,731 pounds curb weight in the case of the OOCC Skylark.

The OOCC Skylark was usually unladen with Spartan amounts of gas in the tank. The Buick Chassis Service Manual states that the full gas tank weighs 122 pounds. Subtracting about 100 pounds from curb weight for the saved weight from chronically low gas tank levels averaged with driver weight brings the usual curb weight up probably no higher than 3,800 pounds. Adding the occasional times the OOCC Skylark was carrying additional passengers might bump the total up slightly.

The type of gas used varied according to convenience, not preference of brand. A surviving receipt from a gas stop at 98,515 miles came from Sunoco. Sunoco was the nearest source for the owner to get 'high test' gas. The twelve high octane fill-ups in the logs are likely also from Sunoco. The 87 octane fill-ups at this time would have contained 10% ethanol which reduces the energy potential in the gasoline and hence cuts the MPG.

The odometer was never checked against mile markers to ascertain accuracy but some speedometer exaggeration may be inferred from theoretical top speed estimates in WORLD CARS. Top speed wasn't attempted in the OOCC Skylark, but it easily cruised at a sustained speed indicated as 100 MPH without being floored. Supposedly, the 1972 Skylark wasn't capable of 100 MPH. Instead of suggesting wild speedometer exaggeration it seems more likely that the WC figure is wrong. Another 1972 Skylark supports this theory. The top speed of the 1972 Buick Skylark Custom in the ONE OWNER section was indicated at 120 MPH with a base 350 two barrel. Even allowing for speedometer error, that car had to be exceeding 100 MPH.

WORLD CARS Book for 1972 pegged the Skylark 350's top speed at 'about 96 MPH'. WORLD CARS relied on manufacturers' information and only used alternate sources if this was unavailable. GM seems to have used mathematics to calculate top MPH rather than directly observing it for each and every model with each drive train. The WC absolute top speed figure has been shown to be underestimated in each instance that a car magazine has actually driven a car at top speed. See the ONE OWNER story on the 1979 Firebird T/A, or the story on the 1974 Fury in GAS LOGS. This isn't to say the speedometer is necessarily right. The OOCC Skylark has a speedometer that like most from this era, probably reads out of whack by 5 to 10 percent.

Calculating the MPG is a bit of a challenge since there are no fill to fill records available. The fragmentary part of the gas log that wasn't lost does have a notation about when the car ran out of gas. Running out of gas provoked note keeping to predict the bare minimum amount of gas that could be used without getting stranded. These notes indicate when the Skylark was down on the E mark on the gas gauge but hadn't run out. The standard gas gauge in 1972 Skylarks has a large sweep area giving a very accurate indication of when "E" is reached. (The fuel gauge provided in optional gauge package is smaller and offers less precision).

Taking the miles between E and E gives a fairly close account of the mileage. The average of the three readings is 11.5 MPG. Taking the entire gas log we get a similar result. It took 210.9 gallons to keep the gas gauge close to empty over 2,385 miles. That works out to an overall average of 11.3 MPG.

Odometer Gallons Octane   Fill?   MPG (uncorrected) 
96,726         2.5       94     X  
96,765         1.5       94     X  
96,793         4.5       94     X  
96,880         4.0       94      X  
96,897         2.0       94      Empty- ran out of gas  
96,908         2.6       87       X  
96,940         5.2       87       X  
96,992         2.1       87       X  
97,000         3.9       87       X  
97,030         1.5       87   
97,058         1.0       87   
97,067         5.3       87   
97,122         1.5       87   
97,142         5.2       87   
97,184         5.0       94

97,280         3.2       94   
97,289         2.5       94   
97,324         1.3       87   
97,379         2.1        87   
97,359         3.1        87   
97,388         2.9        87   
97,438         5.3        87   
97,457         2.6        87   
97,494         1.0        87   
97,511         2.6        87   
97,539         1.3        87   
97,556         2.8        87   
97,579         5.2        87   
97,639         2.6        87   
97,669         3.9        87   
97,702         1.5        87   
97,725         5.2        87   
97,780         3.1       87   
97,827         6.8       87   
97,902         2.5       87   
97,936         3.1       87   
97,983        10.4      87   
98,084         2.6      87   
98,192         5.2      87   
98,156         3.0      87   
98,195         2.0      87   
98,250         3.9       87   
98,279         3.6       87   
98,349         5.2       87    Empty  11.2 MPG
98,411         5.2       87    Empty  11.9 MPG
98,426         0.0       87   
98,464         4.3       87   
98,515         4.7       94   Empty  11.5 MPG
98,556         4.9       94   
98,602         5.2        87   
98,678         3.6       94   
98,712         3.6       87   
98,750         3.1       87   
98,850         6.0        94   
98,889         2.2        87   
98,920         7.8        87   
98,995         4.7        87   
99,042         7.3        87   
99,099         0 0   
99,111         0 0










Flint, MI noon


SU- 0 45 AQ/ MO 8 AR/ ME 14 CP/ VE 6 PI/ MA 16 AR/ JU 26 SG/ SA 29 TA/ UR 18 LI/ NE 4 SG/ PL 1 LI/ NN 5 AQ

SU tr SA/ SU tr PL/ ME sq MA/ ME ssq SA/ VE sq NE/ VE 30 NN/ MA 45 SA/ MA 180 UR/ MA qnt NN/ JU inc SA/ SA tr PL/ UR 45 NE/ NE sx NN

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