"A nod's as good as a nudge to a blind bat, know what I mean?"
- eric idle
I think I track with your intent.
No shocker that your question has languished unanswered... ain't so many Lambda-savvy motorheads and Hyundai hot rodders perusing the sonataforum.com forum for advice, which seems mostly populated by flummoxed shade-tree mechanics and post-warranty grousing. You might have slightly better success with hyundai-forums.com, hyundaiperformance.com, and/or hyundaiboost.com; et. al. I also recommend you post your query within the handful of engine rebuild enthusiast forums (e.g.: aera.boardhost.com; iatn.net; and/or forums.mightycarmods.com.
Yours is a reasonable question, and from your winky-wink phrasing I infer you're curious if you can overbore an aged Sonata's 3.3 G6DB to a 3.8, and perhaps swap in the rods and pistons from a crumbling Sedona (since the stroke is longer). You'll likely encounter a dilemma with the heads though, and it's unlikely that the heads from a 3.8 (Azera, e.g.) will be gasket and bolt-compatible. Seems to me, so long as the min jacket thickness dimension isn't breached and you're spec'ing those values from like engine years, the notion is plausible. Each cylinder might need to be sleeved, which would be necessitated by min wall thickness tolerances and would (duh...) require a larger bore. And hereupon comes my best... comment... ever:
Why are you soliciting responses from strangers? (My hunch is you're merely floating a notion and not really serious, no matter how devilishly crazy your reasons.) You claim to be a mechanic. Hey.. me too! (I'm not) Find a machine shop that specializes in them thar in'jun rebuilds and put ask your questions in person.
I give you the benefit of doubt that you've addressed the obvious question of "why not swap out the 3.8 for the 3.3?" and found that won't work for a litany of valid reasons. Any chance an aftermarket turbo retrofit to your 3.3 G6DB might give you the add'l HPs you crave? I haven't a clue if a cramming more cubic inches of air into the intake will garner you the ~28HP improvement the 3.8 G6DA supposedly has over the 3.3 G6DB, but it might be more do'able in a practical sense.
'Course, the possibility exists that my presumption about the reason behind your post is completely wrong. If that's the case... ignore the five previous paragraphs.
Last edited by lothian; 03-27-2019 at 02:30 PM.