The most common and most likely answer to this crossword clue is the 3 plus 3 letter word BIG END
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More clues leading to the result BIG END
- Epic finale essential to Chitty Chitty Bang Bang?
- Dope stashed in order for engine part
- Dope put in offer for part of engine component
- Info gathered in order to make engine part
- Being around before daybreak, supply engine part
- Attempt to acquire information that’ll be needed to get engine going
- Offer to lag low-down part of machine
- Offer to store data — it’ll be expensive if it goes
- Part of an engine — data in order
Buddy explains!

The straight part
We know that "part of machine" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case part of machine = big end.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.