"The biggest difference is that the disciplines on the Ironman are longer and of course there's the swimming element, too.
"I can stay afloat. It is not a strong discipline. I can swim for an hour pretty comfortably. For me it is getting through that one."
Drysdale hopes his summer exploits will have a positive effect on his return to rowing, with a long term goal of the 2016 Rio Olympics.
"The Coast to Coast pushed to places I don't go in training at rowing - going for 14 hours straight makes you think this is a long day out. That endurance training is going to help me when I go back to rowing. I won't be too much off the pace and won't have to do too much to get back to where I need to be to compete on the world stage again."
He has enjoyed taking on a number of events in his training where he is just one of the weekend warriors, rather than out in front of the pack.
"I've done a number of ocean swimming events and gone out and trained as much as I can. I did the Queen St Mile run, too. It is something that has surprised me, that I have really enjoyed just being involved in events that I am not competitive at, and not winning."
Drysdale will be hoping for some family support this weekend, with his father and two sisters living in Australia, while he has also schooled up on some of the traditions of the Port Macquarie race.
"I've heard it's a pretty good atmosphere and celebration. The crowds are apparently really supportive and I've been warned about the places the fans deem as no-walk zones. I'll have to keep running there."