The Rotorua crew surprised most of the other top schools by qualifying fastest in a time of 4min 27sec across 1500m.
The repechages were rowed over 1500m rather than 2000m as regatta organisers had to make up time after weather delays.
Coach Glen Reichardt said the Western Heights crew were the dark horses in the prestigious race which was generally dominated by rowing giants Auckland Grammar, Hamilton Boys' High School and Christ's College (Christchurch).
Western Heights finished fifth at the North Island Secondary School Rowing Championships last month, but took the other crews by surprise this week.
Reichardt said in their heat this week they really struggled but they pulled out a great effort in the repechage to qualify for the A Final.
"In their repechage they rowed like they had stolen the boat," he said. The only other time in recent history where a Rotorua school has rowed in the A Final of the eights was in 2006 when Rotorua Boys' High School finished fourth.
This year four Rotorua schools - John Paul College, Western Heights High School, Rotorua Lakes High School and Rotorua Girls' High School - have 52 rowers and coxwains competing.
Reichardt said it was one of the biggest squads the city had sent to compete at Maadi.
He said all the senior boys, bar one, had qualified for an A final today or tomorrow, with one rower still to do his qualifying. The A final is the last race of the regatta and will be rowed tomorrow.