They caused significant damage to local roads, in particular the Millars/Longbush Rd area, he said.
"I've seen first-hand the mess they've left and I've spoken with someone from the Carterton District Council who has already had to re-mark the road at considerable expense because the whole road was pretty much black."
There were so many cars, drivers split into smaller groups and even then some roads were backed up with traffic for several hundred metres.
Mr Nolan had spoken to several residents who were feeling "extremely harassed" as the area was often used by boyracers.
Police learnt of the gathering several weeks beforehand and deployed extra staff on the night, he said.
They were also planning to increase resources put towards boyracers.
"I'm confident police made an impact on their activity and that looking ahead to what the district is planning -- an increase in resources -- the impact we will have in future will be a lot greater."
The investigation was ongoing and police were aware of similar upcoming events in the region, Mr Nolan said.
Carterton mayor John Booth said he had been contacted by about 15 angry residents, many of whom felt intimidated.
"Some of them were very scared and frightened."
The boyracers had left rubbish everywhere, urinated in paddocks and left behind a "bloody shambles".
Some roads had to be cleaned and repainted, he said.
"It's all very expensive work to do and another cost that our ratepayers have to bear."
