ive got a b16a2 im about to rebuild and iv also got a old b20 vtec build laying around. would it be a good idea to bore the block and use the b20b crank rods and pistons. p.s. this is a daily driver crx hf

 

Why not just use the B20 block?

 

You cannot use the B20 rod in the B16A block... it will make the pistons stick out of the top of the block. You can use the 89mm stroke B20 crank in the B16A, but it will require a special length rod and custom pistons.

If you had a B16B... you could have done as you originally stated. It has the same deck height as the B18 and B20 blocks.

 

you have apples and oranges, cant inter mix any of that.

 

To add to everything stated above, you also cannot bore out the b16 to 84mm to use the b20 pistons. Stock b16 and b18 sleeves max bore can be 82mm. You'd have to sleeve the block to go that big.
So I would say no to all of it. Don't waste your money trying to get the b20 internals to fit in a b16 block. Spend that money on the B20-vtec. Build that block instead.

 

Sleeve the b20 and put the b16 head on it.

 

I have on sale sleeve darton MID for B16 new in 350. bore 84.mm a 85mm MAX.