Looking for an understanding of what zero decking is and decking in general and why it is required?

 

top of the piston even with deck of the block at TDC, stock you have like .020 of space.

 

So why do you do this, to raise the compression ratio?

 

yes to raise compression.no other real reason.

 

Well, besides raising CR it also makes for a tighter quench distance which can make a few more hp and increase detonation resistance.

Rich

 

Okay here is the deal, I need to either hone or bore my cylinders. I will be installing LE2 heads with Impala head gaskets.

Is there any reason to have to machine the deks on 78K heads that have never been overheated? heads were tight before removal.

 

You should have the decks machined.

 

As minimal as possible or zero deck?

 

The deck is on the block, not the heads. Your heads should be checked for flatness and machined if needed.

 

Yeah it also gives you more head gasket choices... Decking the block helps out in lots of areas, and yes it's always a good idea.

Bret

 

Correct me if I am in wrong, but on my journey to my Mech Eng degree, Mech Eng 153 stands out in my head as "boring is enlarging the hole" and "honing is the refractory process that smooths out any maching marks on the inside cylinder walls and leaves a nice cross hatched surface?"

....or thereabouts....

You hone after you bore correct?

 

Yes but you can also just hone and freshen rings [no boring] if the wear is minimal..

 

like .002 or something is the general rule of thumb correct?

 

With the right tooling you can hone a cylinder to whatever size you want. Boring gives you the ability to PLACE the hole, then you hone it to final size. Honing allows you to size the bore to within a tighter tolerance and give the cylinder a surface finish.

Some CNC machines can bore extremely accurately, you could with a laser etching tool bore a cylinder and then leave the surface finish to spec with a laser.... theoretically.

Bret

 

Thanks all. I will be square decking the block just enough to be flat.

Other than honing, boring are their any other useful things that should be done to the bock.