hi , what bhp would a vers 3-4 sti block with acl race bearings be capable of,. im thinking 400bhp or will the rods and pistons handle more,. steve

 

400 will be the exception not the norm without a forged engine. your gearbox will probably $hit itself as well.

 

The block will run 500bhp, the internals are good upto 330-350bhp, some do more, some do less, its hit and miss but on a car thats 14 years old, i'd personally keep it below 350bhp for reliabilities sake, and as sinky has said, your gearbox wont like it.