why is it necessary to resleeve an h22a when upgrading to forged internals?

 

because Honda used a fiber reinforced sleeve that is not compatable with forged pistons. you will experience serious damage to the walls of the stock sleeves that will cause you engine to loose compression and start to use oil.

 

You will have to resleeve.
Here is a pic of my block done by GE.

 

Even though it is the crappiest magazine ever, ImportRacer did an article on sleeving an H22 last month (2F2F on the cover). It had some good pics and went into pretty good detail.

 

because the search engine says so

 

I too just sent it out to have it resleeved by GE........... for block sleeve, pistons and bore & hone it was $1391 on my H23a......