"It felt incredible," added the Briton, who finished runner-up last season behind now-retired team mate Nico Rosberg despite winning more of the 21 races.
"Yesterday was the first time seeing the car come together. It’s the most detailed piece of machinery I’ve seen so far in Formula One.
"The car feels wider, which it is obviously. The front tyres obviously feel huge," added the 32-year-old, who won 10 races in 2016 and starts the season with a new team mate in Finland's Valtteri Bottas.
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Formula One has undergone big rule changes over the winter, with wider front and rear tyres and different aerodynamics designed to make cars faster, more aggressive and harder to handle.
Lap times should be several seconds quicker than 2016 with cornering speeds putting more G-forces on the drivers, who have had to bulk up and add muscle.
Bottas, who has joined from Williams following Rosberg's decision to retire only days after taking the title, has yet to win a grand prix.
He has already said that he is not intending to play second fiddle to his team mate, however, and the pairing start on equal terms.
"I think I have done the most amount of training of any winter so far. I have done some good training camps and feel in the best shape I've ever been, definitely ready for the season ahead," said the Finn.
The new car was first presented to fans online, with the drivers pulling the covers off the W08 behind closed garage doors before it was wheeled out to the media shivering on the Silverstone straight.
The team were then set to complete a limited 100km filming day in the afternoon with both drivers taking a turn.
"The dominant feeling in the team right now is one of excitement - the factory is buzzing with anticipation," said team boss Toto Wolff, whose team have won the last three driver's and constructor's titles.
"It has been a really motivating challenge to develop a brand new car concept and I have never seen our determination to succeed higher than it is right now."
Testing will start in Barcelona on Monday, with Bottas doing the first stint before handing over to Hamilton for the afternoon.
The season starts in Australia on March 26.
(Reporting by Alan Baldwin, editing by Neville Dalton)
