The Fiero Store Throttle Body is of very poor workmanship. They only bore them out to 55mm. (had one and it caused too many problems)
Click on the Parts Vendor link at the bottom of the page and scroll down until you see Darrell Morse.
He charges less money, ($130.00) Bores out the throttle body to 57mm, and ports your upper plenum to match.
See this thread: http://www.fiero.nl/forum/Forum4/HTML/018916.html
As for heads, I had both of mine redone with a full port/polish, 5-angle valve job, new seals, locks, retainers, and springs for $350. With the poor workmanship I saw on their throttle body, I would not trust the workmanship of their heads.
Happiness isn't around the corner...
Happiness IS the corner.
[This message has been edited by Oreif (edited 03-04-2004).]