hard or soft copper line for a valley oil gallery bypass line?

I just looked at the drawing again because I haven’t studied one in 30 years.

I had forgotten they were blocking oil off to the number one main and then rerouting it from the drivers side.

That was the first clue it was stupid. Then I bought the T/A block W2 headed engine and that guy PAID a hydraulics engineer to fix it. It had a crossover tube and the first thing he did was remove that.

Of course, my dad thought the crossover was the **** and wanted it back on. So one of his life long engineer friends came over and took a look at it. He said it was useless. And it is. In fact, he said the guy who developed it didn’t have a clue what the **** he was doing.

The upshot is getting the leaks stopped at the lifters and forcing the oil to the mains. Again the crossover doesn’t do that. It makes a bunch of work for no gains.