The American carded five consecutive birdies around the turn before finishing with another birdie at the 18th to reach 15-under-par 129 at El Cardonal at Diamante in Mexico.
James, who secured his PGA Tour card for 2027 by finishing No 1 in the PGA Tour University rankings, has enjoyed an impressive start to his professional career since leaving the University of Virginia this summer.
Friday's round was his 14th of 65 or better in 13 tournaments, while he has already recorded four top-five finishes.
"It's weird, in college I was kind of someone that would shoot 2, 3 under every time out and would have trouble going low," James said. "But you adapt to your surroundings as humans, so I guess out here that's what you have to do. I've been rolling it well and playing well, so nice to be shooting some low numbers."
Peter Malnati sits second on 14 under after also shooting a 64, while Zac Blair is a further two shots back following a four-under 68.
"I work really hard on my game and I haven't had tons to show for that lately," Malnati said. "So to not be in that position coming down the stretch on a Friday where ... I don't even have to think about the cut line, I can think about playing golf. That was fun."
It is the second time James has held the lead heading into a weekend on the PGA Tour. He previously topped the leaderboard at the RBC Canadian Open but struggled with a 78 in the third round.
A victory this week would represent another significant milestone for the 22-year-old, potentially moving him into the world's top 50 and securing a place in the 2028 Championship Series under the PGA Tour's new model.
The World Wide Technology Championship is one of the final three events of the FedEx Cup Fall, with the top 100 players in the standings retaining full PGA Tour status for next season.