“SPARE” MOTOR
I’ve been collecting (aka buying, scrounging, trading) parts for the past 2 years so I could build a spare motor for the wagon. This one is another long-rod L20b, +2mm forged flattops with cutouts, prepped crank, big-valve A87, planning 12:1 CR. It’s gonna be really nice having a spare bullet in the chamber when I gotta pull out my current engine.
Did you end up going with a 6″ rod and moving the pin upwards in the piston? I”m looking at doing a long rod setup and trying to get the right piston specs.
Yep, I used a set of prepped 6″ Datsun rods, and had a set of custom forged 87mm pistons made with a shortened pin-to-top distance to give me a flat top with the deck. The numbers are buried somewhere in my garage, but probably available if you hunt around on the web. I just did the math based on crank throw, rod length, deck height, and then ordered them. With a small chamber head, it ends up about 12:1 cr.