- Flathead pistons produced in the 1930's were long, heavy and had completely flat tops. While they did the job, these cast aluminum pistons were behemoths, which ultimately limited the Flathead's rev range and power potential.
- Most Ford pistons are made of cast aluminum. This inexpensive process results in a fairly reliable and inexpensive piston, but one with low strength and detonation resistance. The next step up are the light-weight hypereutectic (high silicone content aluminum) pistons used on many late 1980 and early 90s V8s; these pistons are strong but brittle, so they tend to shatter under pressure. The strongest are forged aluminum (used in many of Ford's supercharged, turbocharged and high-performance engines like the Turbo Ecotec, Taurus SHO twin-turbo, 5.0L H.O. and 427 "Cammer").
- Most Ford engines use a "dished" piston crown that allows more of the combustion event's force to express on the piston top. The next step up is the flat-top (used primarily for higher compression on performance applications like the 5.0L H.O.) Pop-Up Pistons have a dome for high compression. One of the only Ford engines to come with pop-ups stock was the 427 "Cammer," which had to have them to compensate for its massive hemispherical combustion chambers.
- In the 1970's Ford began producing pistons with shorter side skirts to reduce weight and piston side loading. While these pistons were a boon to fuel economy, the casting methods often made them prone to breakage. This was an endemic problem for Ford all the way through the mid-1980s until they were replaced in 1985 with 5.0L H.O.'s forged pistons.
- Low, wide-set piston rings allow a lot of blow-by and produce excess friction, but 1930s casting and materials made close-set piston rings a dangerous proposition. Modern high-strength aluminum alloys and machining techniques allow newer piston rings to ride inside of narrow ridges that would have shattered using older techniques.
History
Materials
Crown Design
Weight
Piston Rings
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