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Old Iron, Times (and Technology) Change!
By Doc Frohmader
For the past 15 years or so I've abused the automotive media and the English language with series after series of vintage engine build-ups. These are opus-length ordeals that consume somewhere between 150 and 250 pages and a lot of photos aimed at doing what I can to re-discover and re-invent various vintage engines for modern uses. They have been very successful.
In the process, I've managed to find or rediscover a lot of details that people who want to build a specific vintage engine really need to get the job done. It seems that every engine has its own unique quirks and oddities that, if not known or sorted out in advance, usually mean something goes wrong with the finished product. Knowing about that O-ring under the oil pump pickup on the Big Cadillacs or the right order of assembly for the pickup tube gaskets in a Y-Block Ford or the valve stem height specs on an OHC Pontiac six is just plain critical.
However, I think another reason these series' were worthwhile is that in each and every case I started with a clean white sheet of paper and no preconceptions. This prevented me from simply duplicating what others have done without considering alternatives, innovations, and application of modern technology. In other words, by not walking in lock-step with everyone who built a given engine back in the '50s, I opened up interesting and productive avenues I'd have missed. It's been both a blessing and a curse.
The blessing side meant that some very nice engines were built that did things they never did before and did them well. I got a hp per cube out of that Y-Block. I deleted 303 grams per cylinder in a Rocket Olds. The FE Ford nailed down 470 hp and 525 ft.lbs with a stock 390 block and bolt-on aftermarket parts. The Pontiac OHC six finally got detailed coverage on critical valve train geometry. It was fun and I got great feedback from the readers and builders who took the ball from me and ran in their own directions.
The curse side is that in EVERY case I have run up against people who resented my intrusion. These are the little frogs who reign over their own little ponds and are content with the status quo. They have had some degree of success, often many years back, with their own specialty and as a result hold a position of respect. It is jealously guarded. Unfortunately, often the way it is guarded is to exclude any and all who would innovate or make any changes to the boiler-plate design and building techniques they use. New is threatening.
I hold no grudges and mean no harm, but I also see that ignoring changes in technology and preventing innovation just means that a lot of out-dated and poorly-performing engines get built. In time these vintage engines get a bad rap as troublesome or unsatisfying so customers abandon them and opt for crate engines for their projects. That means less quality work for machine shops and builders.
Here are a few examples of how little frogs foul the ponds for us all:
There are still people who use plain cast rings when for very little more you can get a modern moly ring that seals better and lasts much longer. There are very few applications where moly rings are not available. Is it just ignorance of the technology or is it a lack of proper equipment to do the right cylinder wall prep?
The same people still use chrome rings on street engines despite the clear advice against it from the ring manufacturers themselves. All they do is chew up blocks with excessive wear and they offer nothing in terms of advantages for streetable engines. Again, is this because machinists do not understand how they work, how to prep for the right rings, or enduring mythology?
Even those who go for the modern rings still want to prep the cylinder walls like they did in 1956 for cast rings. Instead of accepting the ring and equipment manufacturer's researched and proven recommendations, machinists repeat and repeat what they did in the past. They take good technology and turn it to junk with bad machine work and then blame it on the rings. The benefits of plateau honing may be missed by some because they haven't been educated as to why it is done, how it is done, and why it is effective.
If it says in the 1952 shop manual to use .0010" piston wall clearance, that's what they'll insist on despite the changes in piston metallurgy, ring design, engine uses, fuels, and lubrication. It drives piston makers up a wall to discover that when they spec out .0035" clearance that the builder will insist on installing modern pistons at other vintage specs. Of course, when those pistons fail it becomes the fault of the parts manufacturer instead of the genius who refused to accept or understand the changes in technology.
I could rant for days on crank clearances. When a single shell had a tolerance of .001" (we used to buy several sets and mix and match to get corrected clearances on race stuff) and we did not have align hones and we all used straight 30 weight oil and filters were crude if used at all, it made some sense to have .0035" clearances. Now we have micron tolerances, easy access to align honing, 5W30 oils, and vastly improved oil filtering. Excess clearances aerate the oil, reducing lubrication effectiveness, increasing heat, wasting power, and accelerating wear. Big clearances are really an excuse to do poor machine work at this stage of the game.
Gaskets and seals have changed and so have the techniques for installing them. I am surprised to find that builders don't know how to install rope rear main seals and then blame the engine or blame the seal. Or fail to determine that there is a lip seal conversion for a given vintage engine. Or blame the gaskets when a collapsed valve cover or pan rail is warped up enough so no gasket will seal and the engine leaks. Or use gaskets made 30 years ago that are out of date technology and dried up to boot. Worse yet, we still have those who insist that a vintage engine will just leak because it was designed that way and completely ignore modern ways to correct old ills.
Using antique performance parts. This has to do with blindly accepting the idea that once a combination of parts is known to work, nothing can ever be improved. However, what was state of the art performance in 1956, or 1966, or 1986 has often been eclipsed by new technology. If you don't see how these changes affect your engine machine operations and building techniques, then all that knowledge is wasted on you. When designing your strategy for building that vintage engine, look for ways to incorporate the new technology and avoid lock-step decisions. Your experience and constant upgrading to new and improved technology should result in engines far superior to the nostalgic versions. The perfect example was that Y-Block Ford project I did years ago. In 1957, Hot Rod Magazine bragged about getting a whopping 258 hp out of a 292 cube engine, using the best of what they had in the day for streetable engines. My project 292, in 2000, got 315 hp and there was a LOT left on the table (it was a conservative build).
So what does this rant mean? My point is that when you build vintage engines you owe it to both your customer and to your own quality reputation to take advantage of the machine operations, equipment, and techniques you can find. Sticking with what worked 30 or 40 years ago just means that you haven't learned anything since. Refusing to embrace improved technology means that no matter how otherwise skilled you are, how good your equipment is, or how carefully you assemble, you will always be missing the mark and delivering less than the best.
To avoid this quagmire, take the time to bring yourself up to speed on the equipment, techniques, and components available. No matter what else comes of it, you will have a better understanding of the science of engine building. I assure you that the more you understand about how your machine operations and building procedures affect engine function, the better your work will be, the fewer complaints or failures you'll see, and the better your reputation will become. Both your customers and your wallet will thank you.
Finally, from the perspective of your own personal satisfaction, this constant upgrading of your knowledge and skills means that you'll move from modestly skilled procedure follower to craftsman status. You know that feeling when you've done something particularly well - especially when it was a complicated or difficult task? That is pride in your craft and the difference between a wannabe and a serious professional.
The same goes for moving from the insecurity and self-doubt (that nagging feeling the rest of the builders have left you behind) to the confidence of knowing you can walk the walk with the best. New and different should be embraced as opportunities and not as enemies or before long you, too, will become a thing of the past. Make new technology work for you.