Is it possible to increase the bore of the B18C5? What sort of pros and cons would result?

 

Factory pistons are offered in .5 and 1mm oversized.

You will need to take the block to a machine shop and have them perform the proper boring operations and then hone.

Advantages - Increased dispalcement, more HP/TQ
Disadvantages - Cost

You can only go as far as 82mm on stock sleeves. You can always sleeve your block and run 85mm, as I did, which makes it a true 2.0L motor.

 

pros: you gonna have fresh rebuilt motor,
cons: just making it larger bore won't give you too much gains. other mods are needed ==> money

 

82mm w/ 89mm stroke = 1880... aka 1.9L

I've seen them do over 210whp easy.

 

92mm Crower crank, with 82mm bore.