It reminds me of a similar event that happened when I was right seat
in a Cherokee coming back from a small airshow in NZ. Chris (who does
post in r.a.p from time to time) was flying and we had been queuing at
the hold point for some time. It was about 5.15pm local and the day
had been fine and clear. I don't recall the exact temperature but it
would have been about 95F.

I was looking out the right hand window during the takeoff run looking
at the now lengthy line of aircraft waiting to take off from the two
runways available. Chris asked me if I had my feet on the brakes. I
recall mumbling something in reply which made him repeat his question
firmly. That got my attention and I replied clearly this time that my
feet were flat on the floor and clear of the pedals. I looked up and
the marker boards at the other end of the grass runway were fast
approaching and there were people ahead about 500 feet past the
threshold striking tents that had been in use during the airshow.

Chris made the decision to continue with the takeoff and we just got
into the air before running out of runway. We cleared the people past
the runway by about 40 feet and continued to slowly gain altitude and
airspeed. It was about that time I glanced at the CHT and it was a
lot hotter than it should have been, as we had been sitting stationary
on the ground with the engine running for at least 20 minutes.
Combined with the hot day (altitude was not an issue, the runways
elevation was only 12 feet above sea level), 4 people on board and a
hot engine, our takeoff performance was vastly impaired. As we set a
cruise climb attitude the CHT returned to normal and our climb rate
increased back to normal as well. The rest of the trip was
uneventful. We discussed the incident during the flight and talked
about what we would do differently next time. I think we both
realised how close we had come to what could have been a major
accident.