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A Historical Perspective On Performance by Stirling Watts


A Historical Perspective on Performance:  The 80s Versus Today

By Stirling Watts

At left:  Old school fuel delivery – Two 40mm Weber DCOE dual throat carburetors fitted to our 1959 Alfa Romeo Giulietta Sprint Veloce

What is History to One, is Fond Memories to Another!

Only recently has it come to my attention that my own recent personal experiences are, in the eyes of the younger adult generation in fact, history!   That which I remember about all the fun I ever had racing motorcycles and carts and automobiles is to me as clear as is any other memory.  To those who were not yet born in the early 80s, that which is to me the mundane might be to them quite interesting.   Without that realization I never would have considered assembling this article. I certainly feel amazed when I read all the material that Bob Watts has contributed about racing in the early 50s, just a few years before my own birth.  The memory of a world in which cars from the 1930s were an everyday experience is to me like fantasy, while to Bob it is just a memorable reality.

Though I am no detailed technical authority on the subject of internal combustion efficiency, I lived through the era of the 80s paying at least some attention to it, while the average citizen did not.  Not everything I write will reflect the truth as my world of experience is quite narrow, and I only state things as I remember them and with respect to that which I was privileged to witness.  When I started fooling around with increasing the performance of standard engines was during this period, the early 1980s.  It was a good period for the motoring hobbyist, for it was a period during which off- the- shelf engine  efficiency was still in its infancy.  Under my Dad’s tutelage, I gained the majority of my guidance from a classic book which is still in circulation in reprint, entitled “Tuning for Speed” by Phil Irving.  Irving was a renowned Australian motorcycle engine designer and tuner who knew and understood, through vast amounts of practical experience in racing as well as professional work as an engine designer, how to make standard engines perform to their maximum potential.  His experience was well documented  in this classic book, which I think was first published in the late 1940s.  “Tuning for Speed” by Phil Irving was my Dad’s Bible.

The Era of Federally Mandated Dismal Performance

Looking back on it, motorcycles and automobiles have advanced to a highly reliable and advanced state in the past 30 years.   In my childhood and teen years, performance cars were all leftovers from the 1960s. Late in the 70s and in the early 80s in the automotive world, government mandated pollution controls were initially a great hindrance to performance.  There was a brief period of low performance “high performance” vehicles.  In that era, the requirements imposed upon automotive manufacturers for cleaner air were in excess of the capabilities of existing technologies.  Such standards could only initially be met with adverse effects upon performance.  Rather than focusing on finding methods to increase combustion efficiency, automotive engineers were, at least  in the short term, compelled to use “band-aid” fixes which focused on a less efficient approach to cleaner exhaust air, namely, burning off the leftover gases after the fact,  as opposed to finding more advanced methods to improve combustion in the power cycle itself.  Evidence of that state of being behind the curve could be seen under the hood of virtually any common period car.  The plumbing under the hood of just about any car of the late 70s or early 80s  was almost mind boggling.  It was also a major confusion factor for even the best mechanics.   Fuel injection technology was still less than perfect.  Many manufacturers chose to continue to rely upon carburetor technology simply on the basis of cost control.  But meeting the clean air standards required more control of fuel mixture and delivery than could be delivered by traditional carburetion systems.   Hence, fuel and exhaust systems became extremely complex.  On top of all of that complexity was relatively poor performance with respect to what we see today.  Look, for example at the output specifications of a 1979 Chevrolet Corvette, or that of a 1979 Pontiac Trans Am.   I clearly remember renting a California model 1979 AMC sedan of some sort while on a business trip to San Diego.  I could not believe that people were willing to buy new cars with such dismal performance.  I felt similarly about a Ford Pinto I once rented for a couple of weeks in 1979.

The Advancement of motorcycle performance was less restricted by government interference.

Motorcycles did not suffer exactly the same fate of directly strangled performance, due to the fact that the EPA chose to attack motorcycles on a more relaxed and delayed schedule. But the motorcycle industry did in fact have its own set of government interference problems with which to deal in the 80s, including some market interference laws which compelled the big four Japanese firms to market 700cc machines in place of the already established 750cc standard.  Later in the decade of the 80s came also an “anti-horsepower “ movement, during which propositions were under consideration which threatened to limit the maximum performance by federal mandate.  “Horsepower kills” was the motto of the day.  Intelligent lobbying efforts eventually killed the proposed horsepower limitations.

As time went on and technology began to catch up with government mandated standards, engine efficiency improved.  This state of affairs led to the almost incredible state of reliability and performance which we witness today, and which the younger generation has no capacity to appreciate.   Before them e development of advanced engine and mixture control by computerized mapping, every single change or flow improvement made to an intake or exhaust system  resulted in an unknown and difficult to predict change in mixture requirements.  “Plug reading tests” in the field, combined with a developed understanding of and a good feel for understanding the various stages of a carburetor (main jet choice, needle choice, needle position choice, pilot jet choices, were necessary in order to be able to tweak maximum performance from a motor.  Few with the exception of those with excellent mentors and/or a wealth of experience really could properly tune a race motor.  Myself included, I witnessed this many times testing new motors at club racing events, at which I had wished my Dad had been present!  Only those with unlimited budgets had or have access to dynomometer facilities with which one can at least find an approximately correct setup before going to the track in a relatively casual manner.

Today’s Amazing State of Tuning and Efficiency

Today, with the exception of those who continue to enjoy vintage competition, those days are gone.  On the down side, there are probably few real tuners in this world anymore.  With computerized mapping controlling everything from fuel mixture under every possible load and engine speed condition, to real time changes in camshaft and ignition timing, also calculated as functions of load and engine speed, no real tuning ability is needed.  Today we can swap out and ECU with a different pre-assigned set of mapping functions, and completely change the output characteristics of a given engine.

Most impressive is for example the new Fiat engine used in the car currently known as the 500.  My son, Eric recently purchased an Abarth version.  We were surprised to learn that off-the-shelf performance improvements can be implemented by virtually anyone, by simply pulling out and replacing an ECU chip.  All of the tuning has already been done flawlessly and perfectly by someone else!  One can purchase a chip directly from Fiat engineering people which will change the mapping from the standard 160 bhp in Sport mode) to 200 bhp!  No intelligence required!  All for around $600!

Perhaps it is difficult to grasp just how amazing this is unless you have yourself attempted to adapt a new set of carburetors to an engine to which you have made other mechanical and airflow modifications.  Our 1959 Alfa Romeo Giulietta Sprint Veloce is a good example.  A few years back we discovered that the original dual double throat DCO3 Weber carburetors were completely worn out, such that with them it was no longer possible to balance the airflow between the cylinders.  We purchased a set of more modern DCOE Webers as a replacement.  Thanks to the skill of our friend Peter Smith, an experienced old school tuner (who by the way also was  the 1970 SCCA Can Am 2 Liter National Champion in a BMW powered Lola chassis), the newer DCOEs were finally brought into a state of tune which allows tolerable drivabilty.    But that was no small task!  It required repeated removal, modification, retesting, and rebalancing until the effort was perfected. More on the Alfa Sprint Veloce in a future post!


Complexities of a Weber 40 DCOE System

What Promises Does the Future Hold?

If you are much younger in years than the author, you might not have had the opportunity to grasp just how amazing is today’s technology.  Just imagine what another 30 years might do!  Some younger reader will, it is hoped, in the now seemingly far off year of  2043,be found writing fondly about the good old days in 2013, about how crude and undeveloped was technology in that era, perhaps back in the days when cars had wheels and internal combustion engines.   Happy Motoring!