Kire Ivanovski, 53, first came to police attention when he was seen driving his white Holden Commodore at high speed near Goulburn around lunchtime on Valentine's Day.

Police said they received multiple calls from concerned motorists about Ivanovski's driving, with people estimating he was driving at about 180km/h.

Yass Highway Patrol officers clocked Ivanovski travelling at 205km/h as he approached them. When he drove by, he put his right hand out the window and stuck his middle finger up at police.

Officers did not give chase due to Ivanovski's excessive speed.

Court documents said Ivanovski passed an off-duty sergeant so fast at one stage he caused the officer's vehicle to shake.

"The officer estimated [Ivanovski's] speed was in excess of 220km/h," police said.

Ivanovski eventually exited the highway at Gundagai and the car came to a stop on nearby William Street.

Police approached the car and told Ivanovski to get out but he refused, forcing them to pull him out.

Officers found four knives in the vehicle.

Ivanovski was taken to hospital for a mental health assessment before being charged with speeding and dangerous driving.

When questioned by police, Ivanovski proudly admitted his top speed had been 230km/h.

"If I hadn't of ran out of fuel I wouldn't have stopped," he said.

Ivanovski pleaded guilty to both charges in Wollongong Local Court this week.

In court documents, police said Ivanovski's actions presented an "extreme danger" to himself and other motorists.

"The speeds the accused was travelling at were between 180-230kmh in a signposted 110km/h [zone]," they wrote.

"The accused showed total disregard for all other road users. If he was to have had an accident at this speed the results would have been catastrophic."

Ivanovski will be sentenced in August.