It's widely (and incorrectly) thought the Richie Brockelman character (played by Dennis Dugan) was introduced here, and would be spun off into the short-lived Richie Brockelman, Private Eye (1978) (premiering three weeks after the original airing of this episode). The character had already been introduced in a pilot film, Richie Brockelman: The Missing 24 Hours (1976), which had aired a year and a half prior.
Rocky tows Jim's trailer to the mountains, because Jim and Richie are being stalked . Other than the early first season episodes, where the trailer's parked on Ocean Blvd, this is the only time it ever leaves 29 Cove Road.
One of the very few episodes in which Jim lets someone else not just drive his Firebird, but to do so in a high-speed chase. The last person with that privilege was Doris Parker (Sharon Spelman) in Profit and Loss, Part 2: Loss (1974).
Jim makes a phone call to Beth Davenport. As Gretchen Corbett's last on-screen appearance in the series was several episodes prior (The Attractive Nuisance (1978)), this is the last mention of Beth Davenport for this season (her name would be brought up in one more episode - "The Jersey Bounce" (1978)).
When Jim and Richie are overlooking the construction site in Deadrock, Jim says to Richie; ' I guess people underestimate you all the time, don't they, son? Richie's (lips) reply 'always,' but, he's been looped-in to say; 'oh, yeah; count on it.'