KB167 piston question

[tkkruzer]

will these pistons by them selves give me zero deck? are they closer to the top of the deck than stock pistons? if I use these pistons with 302 heads without decking the block what comp. ratio will I have?  these are going on a 318, but nothing says they are zero deck pistons,i'm just wandering if anybody has used them. any info would be appreciated..thanx guys TK

[John_Kunkel]

If your block is at blueprint spec for deck height (9.60"), the 167 will give you near zero deck.

The actual CR will depend on chamber volume and gasket thickness.

[tkkruzer]

where do i measure on the deck height to get 9.60"  and the reason i ask is because KB doesn't say zero deck concerning these pistons and i was just wandering if the only way i could get zero deck was too deck the block. so any way thats the whole point of this question. thanx guys :icon_smile_cool:TK

[John_Kunkel]

9.60" is the factory spec for the block deck height, if you add up the half stroke of the crank, the rod center-to-center distance and the advertised compression height of the KB167 piston you will be within a few thousandths of the 9.60" dimension. Whether or not it is actually there depends on how well the factory machined the block and any subsequent surfacing.

[tkkruzer]

cool :yesnod:the reason for all the questions is all the articles i have read none say how much they decked the block, the most they say is judisiuosly, what ever that means. i'm wanting to kick up the compression on my 318 and want to get my facts right. is it nessesary to deck the block if i use kb167's or will they work alone? no sence in spending money if i dont have to. what would you guys do in this case? thanx                                                    :icon_smile_cool:TK

[John_Kunkel]

Because of production tolerances you'll never know what the actual deck height is without at least partially assembling the bottom end. If you install the crank and one rod/piston in each corner you can take the exact measurements. If the block is unmolested, don't be surprised to find the piston deck height varies from side to side and from front to back.

With the dimensions known, you can then make the decision on whether or not and how much to machine the block decks.

[tkkruzer]

thanx for the info guys, now I know what to go.  TK