760 ignition timing retard for rear cylinder

[bored&stroked]

What was the reasoning for the timing retard on the rear cylinder when the 650/701 motors in couches never ran that? How needed is it on couches?
I want to build a 760 for my raider. I have a full 760 ignition setup lying around to use. Do I grind the retarding spot off the flywheel, or is it a better idea to leave it factory?

 

[WFO Speedracer]

It has to do with pump loading and crankshaft torsioning or twisting of the crankshaft along its axis, the bigger you get on motor size the more this becomes an issue, the rear cylinder actually runs behind the front cylinder by x # of degrees so they retarded the timing and lower the compression on the rear cylinder on couches, on a standup or blaster I wouldn't be concerned with running the same timing on both cylinders or running equal compression on both.

 

[fx1mark]

Rear Cylinder Piston Seizures – Group K

groupk.com

 

[Sparkplug]

Pto end of a engine always see more wear and heat. Like mentioned it's exaggerated the larger the displacement. Timing and compression can compensate. I imagine the 701 would have had it if it wasn't grandfathered from the 6m6 platform.

 

[Flash-FX]

Interesting read on this subject here from Harry Klem... https://groupk.com/index.php/rear-cylinder-piston-seizures/