After doing a search on eBay, I found quite a few parts for a DIYer to
modify their Elatras. I was wondering if anyone had any insights to some of
them for example, the air intake mod....is supposed to give a 10hp increase
in addition to a small increase of fuel efficiency.

There is also a chip that can added for an additional 20hp but I am a bit
leary of that one.

I have also read on here and other forum sites the use of a synthetic oil
will boost fuel effenciency as well.