Tomorrow I'm taking my B16A block to machine shop to be sleeved and bored out for 81mm forged pistons and rods.

Now I'm very new to motors, so please help me, for 81mm forged pistons does the block need to be bored out at precisely 81mm? what about piston to wall clearance and the piston rings?

should it be a little bigger than the pistons? I'm a little lost on this subject

Any help would be greatly appreciated!

 

based on what you are asking, you not have the knowledge to say the machinist I want to run x PWC.

So you take the pistons and rings along with the block, talk to him about your HP goals, based on that he make the final hone and set the rings to the PWC accorded to your goals. He also can assembly your short block or give to you the pistons with numbers in which cylinder they go with the rings assembled ready to install.

 

lol stock bore is 81mm so I think you mean "honed" which is essentially getting the glaze off the cyl walls. Atleast get 85mm darton MID sleeves that way you'll at least have some torque.

 

@b_swapped93 I'm getting the block sleeved with the Dry Darton Iron sleeves already and they need to be bored to 81mm because its all Darton sleeves are smaller than the standart 81mm.


@Carlos8 Thank you, assembly and the rest should not be a problem. Its only the PWC that was an issue because this is the first time im taking a motor to get bored/honed.

 

I have the impression that he already have the Pistons 81mm. This is my case I already have forged pistons 81mm when bought the block with new sleeves, so I just get a final bore/hone to .0030 PWC

If you go to run turbo not bore more then 84mm.

 

I'm aware of the dry sleeves, but if you're spending all that money why not go over 81mm you'll still have a torque-less 1.6l at the end.

 

I do have the 81mm forged pistons already so the cylinder is going to stay at81mm bore, and the engine is turbo'd. so a .0030 PWC is enough? or does it differ from piston manufacturer?

 

your pistons should have come with a spec sheet with recommended p2w clearances. just set it to whatever is recommended since you obviously have no idea what you're doing.

 

Basically all forged pistons come with a data sheet from factory with the recommended PWC. But many people based on experience and the combination, purpose and HP of the engine run loosen or tighter PWC.

The brand and silicone content of the piston, play a big role on this due to expansion characteristics.

Now with that being said me and my buddies we have build several engines from D.D. to drag. I like to use .0030 to .0035 in any in the range of 350-500 hp.

Hint, Email or call your piston fabricant for recommended PWC.

 

Id be wary of the machine shop that hasnt done honda sleeving before. be sure and check.

If they dont know what they are doing, you could have a paperweight really quick.

 

^^This

Why didnt you go with a larger bore piston? To me, that doesn't make a ton of sense, but then again, i'm not convinced you know what you're getting into either