it is not in production anymore, but it was a crancshaft and con rods, which had deeper stroke, bringing the output of the 4AG to 1.7 liter.
if you want more output, go to the next junk yard, and get yourself the 7A-FE block with internals and accessories, get a porche 924 timing belt, and install the 4AG pistons on the 7A block, put the 4ag timing belt crank pulley adn you will go 1.8 liter, in a much cheaper manner!
7a-fe's could be found in early avensis, some carina E's, some celicas as well.
Edit: Club 4ag had some info about this back int he day. let me see if I can find it.
Here it is: