Bore vs. stroke

[Paul Workman]

Found this engineering discussion that come into play when deciding on which way to go. Enjoy!

https://www.youtube.com/watch?v=UV3RwBPqznU

[bb62]

Paul,

Interesting video, but it gets a lot more complicated than that when engine designers have to take into account emissions, packaging, heat rejection (at the vehicle level), impact on accessories, weight, durability, reliability, driveability and combustion chamber design (though he did hint that the last two). For example, the first (large bore) design is by far the most difficult to emissionize due to the large crevice area between the pistons and the rings.

One interesting example was the Ford 4.6L engine. Performance enthusiasts wanted a larger bore/stroke ratio when the "Modular" engine was launched, but because the engine was to be installed in an E/W application (the FWD Continental), there were limitations on the base architecture and the space for increased bore size. Sound familiar?

bb62 (Mark)