Sadly so many , trailer queens or might as well be , owners make no attemept to replace old systems brake systems , ignition systems , chassis components etc. and leave , or "restore" their cars back to level of ALL the faults it had out of the factory.
There are now companies repairing and or making new hi-performance drum brakes, for those who do not want to go to the expense of putting on discs.
Any one driving a performance car with all the smog gear in place , at least in states where you can remove it one way or another is driving a look at me car.
There are new carburettors now that can be adjusted for all aspects of engine performance, easily, you do not have to take it apart for adjustments they are not cheap but cheaper than todays factory computer systems.
Any one who compares cars of fifty years ago, in the state they were made, tires and suspension even more than engines, is doing the equivalent of Three-Card-Monte.
The fuel mileage often comes from computer controlled cylinder shut-down, which if you are cruising down a free-way makes lots of sense.
But gas mileage, THAT, is some thing Detroit threw in the garbage after the very early sixties when compact cars were the hot sellers when many secretary cars had mileage well into the twenty mpg zone.
In the old Mobile Economy Run, after the first AMC and Studebakers pissed off the big 3 Chrysler products were the best of the best.
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The event was a marketing contest between the automakers. The objective was the coveted title as the Mobilgas Economy Run winner in each class. However, starting in 1959, entries were judged on an actual miles-per-gallon basis, instead of the ton-mileage formula used previously which favored bigger, heavier cars.[2] As a result, compact cars became the top mileage champs. In the 47-car field for 1959, a Rambler American was first - averaging 25.2878 miles per US gallon (9.3015 L/100 km; 30.3694 mpg‑imp) - while a Rambler Six was second - with an average of 22.9572 miles per US gallon (10.2458 L/100 km; 27.5704 mpg‑imp) - for the five-day, 1,898-mile (3,055 km) trip from Los Angeles, California to Kansas City, Missouri.[2]
The efficiency of models as AMC's more compact Ramblers caused them to be all but banned from the event. As a result, Ramblers and Studebakers were put in a separate class. This was because the 'Big Three' auto makers (General Motors, Ford, and Chrysler) did not have competitive cars at the time and were trounced in the fuel efficiency rankings until they introduced smaller platforms (GM "X" body, Ford Falcon, Chrysler A platform).
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Category: Hemmings Classic Car
Crossing the finish line after traveling 3,310 miles from Los Angeles to Boston in the 1966 Mobil Economy Run, this Plymouth Belvedere I won Class C: Intermediate-Size Sixes, posting 23.10 miles per gallon. Despite being set back by a slow leak in a tire, it still bested a Buick, Pontiac, Oldsmobile, Chevrolet, Mercury, and an AMC.
By 1966, the Mobil Economy Run had been illustrating the fuel efficiency potential of new cars in real-world driving conditions for numerous years, and had also served as a marketing tool for the company and the automakers.
Cars were purchased from dealers by the United States Auto Club, the event's sanctioning body, and precautions were taken to ensure that the cars were stock and remained that way. Yet actions by some of the manufacturers' teams during vehicle break-in and prep, paired with intense fuel consumption-reducing driving techniques, meant that a typical owner would be hard-pressed to achieve the same miles-per-gallon figures.
Plymouth stepped up to produce three winners in the 1967 Mobile Economy Run from Los Angeles to Detroit, and the Valiant in Class A: Compact Sixes also posted the highest overall fuel mileage at 24.57 mpg. A Barracuda won Class B: Compact Eights with 22.31 mpg and a Belvedere II topped Class D: Intermediate-Size Eights at 20.01 mpg.
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Now take one of those compacts from back then and put on a after-market computer run fuel injection system, (There are so many out there now, you can now put on on darn near any post WW II car made)
and see what the old school would get then.