I give it to Naruto 7/10 times.
TBB is too much for Luffy to handle right now.
If he gets hit, hes done.
Luffy does however have an insane amount of stamina where he could outlast Naruto's BM for 8 mins. Luffy fought with an enemy stronger then him before for more then 15 mins straight and that was pre time skip. He wore down the enemy and beat him with his last bit of strength.
Post time skip Luffy has so much more going for him, including CoO haki which allows Luffy to see a move happen before it is even done. That alone will give Luffy the edge over Naruto since their speed is about equal.
Of course it is a bit of a stretch to say Luffy can last that long and not get one shotted which is why I give it to Naruto more times then not.
Also, @ the people who know anything about One Piece. Why do you even comment? Is looking stupid less important then getting your post count up, or do you not care if you are shown to be biased and have no credibility.