The 20-year-old had failed to find the back of the net since October and his match opener in the 18th minute ended his 14-game barren spell in front of goal.
'It (not scoring) has an effect because it plays on your mind, ' said Abraham, who was signed on a season-long loan from Chelsea by Carvalhal's predecessor Paul Clement. The Terriers prevailed 4-1. He stated that County need to stick to their game plan and that "if we can get on the end of a set play hopefully we can capitalise on that".
Spurs play their fourth round replay against fourth-tier Newport County at Wembley Wednesday after a 1-1 draw away.
The procession continued after the break with goals from Kyle Naughton, Wayne Routledge and Tom Carroll - whose handsome curling effort was the pick of the bunch - as well as a memorable debut strike for Daniel James.
Swansea's demolition job means boss Carlos Carvalhal can look forward to a fifth round trip to Sheffield Wednesday, the Championship club who sacked him earlier this season.
"It is important if it is the best result in the history (of the club), but the most important thing is the attitude of the players that made all the difference", Carvalhal said.
"I don't think they deserved to be 8-1, but it is one of those games where their finishing was Premier League standard".
"I'm very happy", he told BBC Sport.
Huddersfield was another victor in the fourth-round replays, beating second-tier Birmingham 4-1 after extra time to set up a last-16 meeting with Manchester United three days after losing at Old Trafford in the Premier League.
Dutchman Rajiv van la Parra scored from a rebound to swiftly make it 3-1, before Tom Ince drove in a fourth on 106 minutes to secure the Terriers a clash against United.
In the other match, the FA Cup dream is over for Millwall's Australian duo James Meredith and Tim Cahill after the Lions were beaten 1-0 by Rochdale.