Fernando Alonso was left reminiscing about Formula 1's lack of engine noise after a brief outing in a V8-powered McLaren on Monday.

The Spaniard was taking part in the car swap with NASCAR legend Jimmie Johnson in Bahrain and less than 24 hours after ending what could well be his final F1 race in Abu Dhabi, the double world champion inadvertently found himself back behind the wheel.

"It was not planned to be honest," said Alonso. "I was supposed to only drive the other car but it made sense if I was doing the installation lap just to make sure the car was feeling OK.

"I found myself in the cockpit at 11am this morning after retiring yesterday."

And in that lap plus the rest completed by Johnson, Alonso admits the scream of F1 between 2006-2013 was welcome in comparison to the V6 turbo whoosh of today.

"It was a lot of fun even if from the inside of the car the noise is not so different compared to the cars we are driving now," he noted.

"But even from the outside, it was again something very, very special. So, we are missing a lot of action because of the sound right now."

The noise is one of the reasons many believe Alonso has fallen out of love with the sport, calling time after 17 years.

Fernando insists, however, he has plenty of good moments to remember in retirement and he'll always be a fan.

"There are things that I will miss from Formula 1, things that I will not miss, and I will try to take the positives," stated the 37-year-old.

"It's going to be a good memory. The whole package in F1 was a fantastic journey.

"From a young age until now fighting always in any circumstance, in any car, and I think achieving a lot of success that I never expected.

"I will come back maybe one day as a tourist, as a commentator maybe, and enjoy F1 in a different way."