Last time out, we did the prep work: measuring the standard crank inlet duration (156°), marking up our new 185° window, and making the cuts to the crank webs. Unlike my usual method, this was deliberately stripped back. I didn’t touch the casings on the opening edge, and didn’t shape a flow-optimised ‘scoop’ on the crank closing side. Instead, I used a slash cut with an angle grinder, removed 9mm from the opening edge and 12mm from the closing side, and called it done.
The idea was simple: show what’s possible with minimum effort, using tools the average home mechanic will have knocking around in their shed. No specialist tools, just a grinder, a scribe, and some patience. And now, with the crank reinstalled and the motor rebuilt, it’s time…
