Old School vs New School: Ideas on Carburetion
by Charles Clark
Originally published in the May-June 2020 issue of Continental Comments (Issue # 354.)
Among old car aficionados who do restorations, there is a tug-of-war that goes on. Pulling in one direction are the purists who strive to make the car exactly as it came out of the factory. They obsess not only over “matching numbers”, but also over inspection paint marks on the frame. Those details have nothing to do with how the car runs. Instead, it has to do with the compulsive nature of the restorer. They insist on a level of perfection, which, in a lot of cases, never existed. Corvette restorers perhaps epitomize that approach. On the opposite end of the spectrum are those who seek to “upgrade” the car by modernizing various systems, such as engine carburetion and brakes. At the far end of this spectrum, we have the “restomod” where only the body is saved, and almost everything else is replaced with modern systems.
Our local LCOC region has members of each type, but the emphasis seems to be more on preserving and driving the car while having some personal enjoyment with it. I have engaged in both aspects of the hobby. With my 1940 Lincoln-Zephyr Continental Cabriolet (whew), I strived to do an exact restoration. Why else would I pay $500 for an air cleaner or $300 for an original taillight, and let’s not even talk about the NOS steering wheel? My goal was to make the car just like it came off the showroom floor. But this is 2020, not 1940 and things have changed. Thanks to our beloved “corn gas” and its ten percent alcohol content, if you want to drive the car
here in the Centennial State on a hot day at this altitude, it is essential that you have either an auxiliary electric fuel pump or good hiking shoes when the car vapor locks. Unless the car is to be a permanent resident at the Forney Transportation Museum in Denver, Colo, it must have the electric pump. Otherwise, the Lincoln is as close as I can make it to factory original.
The Continental is, therefore, in line with the stated purpose of the LCOC, which is to preserve the various Lincoln and Continental models. The emphasis is on exact restoration with judging and awards that foster this end. I am proud to say I have received some of those awards, even though I had to take some liberties by making modifications for the sake of practicality.
My 1940 Ford Coupe is at the other end of the spectrum. It looks original, but it has a modern overhead-valve, fuel-injected engine, power disk brakes, independent front suspension and a nine-inch rear-end, plus air conditioning. It is not quite a “restomod,” but it certainly is a “hot rod.” It required special skills beyond my ability to build each car. Machining the engines, painting and upholstery are tasks that require craftsmen regardless of your objective for the final restoration.
I have become heavily involved with carburetion in both “restored” and “upgraded” cars. I use the word “carburetion” in its most basic definition, which is the mixture of air and fuel to provide an optimally combustible vapor. Once the mechanics of the engine have been established, such as bore and stroke, camshaft profile and valve train, there is only ignition timing and carburetion left to determine the ultimate performance of the engine. The design approach to carburetion will have a significant effect on the performance of a car. It took me many years to study and to practice how to carburete an engine optimally. I am still learning.
The “old school” way to carburete a car is to use what we commonly call a “carburetor,” or just carb for short. The “new school” way is to use electronically controlled fuel injection (FI). What may not be obvious is while they both do the same thing, they do it by different methods. A “throttle body” style of FI presents an appearance very similar to a carb.
Why the change? To make the carb engine run at high altitudes here in Colorado, you need to change jets and metering rods. This requires mechanical assembly and some trial and error with replacement parts to get the car to run optimally. You also have to set a fussy thermostatic spring choke to get it to start and run when cold. There is also a power pump and fuel bowl needle valves, which need attention. Fuel starvation due to vapor lock is a common problem.
With FI, you have to make changes to the fuel pump and plug in some new sensors to measure engine performance. Once that is done, a computer takes over and provides the exact amount of fuel the engine requires based on what the sensors measure. There is nothing to change or to adjust with temperature or altitude.
For a judged show car, you want to keep the carbs. For a more regular driver, there is a good argument to convert to fuel injection. The issue then is not so much old school versus new school, but rather what your expectations are for the driving experience with the car and how dedicated you are to the exactness of restoration. That said, be prepared for controversy as “old school” aficionados do not give in to “new school” easily. In fact, they never give in!
