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I am building an engine hoist framework, to hang a chainfall. I will be
using it to pull and install engines and trans in my racecar and other
various vehicles. I planned on using 4x4's for the uprights and the top
crossboard. The crossboard, that the chainfall will hang from, will be
10' long. Is a 4x4 strong enough, or should I use a 4x6, or something
else entirely? I figure the engine/trans combos shouldn't be more than
700 or 800#. Plus maybe a momentary higher weight when a mount hangs up,
and the front of the car lifts up a little with the engine. Any
comments/thoughts are appreciated! Thanks, Big E


A 4x4 will definitely not be strong enough. I have one made up with double
2x8's with a 7 foot width that I have pulled an engine with. I would keep the
width as short as practical. Do not drill the beam to attach the hoist, make a
metal strap to go around, or use a nylon sling wrapped around the beam.

Here is a program that will calculate the bend in a wooden shelf or beam, just
put in various measurements and wood type. Best to size it for ordinary wood:
spruce, pine, etc. unless you can get Douglas fir.

http://www.woodbin.com/calcs/sagulator.htm

--
Dennis