well i was wonderin how far a solid deck iron block (nissan ka24de) can be bored as apposed to an open deck aluminum block(b18c1)? see i figured us hondas have such tight limits to only .5mm overbore because the open deck sleeves limits how far out you can go and also the fact that its aluminum. im guessing a closed iron block can be bored more, no? anyone who can enlighten me, do so

 

see the thing is that, you can indeed go furthur with iron, however if you get damaging detination in the sleeve area, the block is not good. with aluminium u can cut that bad sleeve out and replace it. this is just my opionion, but if u have Iron you should be conservative with the boring and just make up the rest with pure boost. replacing a whole block would have to suck. also the limit the B18 has for boring has nothing to do with the block. its the size sleeves that honda put in it that has the limit, you can put Big custom 87mm sleeves in if you wanted to.

 

Well the most you would ever want to bore a SLEEVED B series block for boost would be 84.5mm.

Some people bore out the B20 block to 85mm for boost...but that is just a little too risky for some.

And with a stock B series block for boost...the closer you keep it to the stock bore...the better. You want as much material in the cylinder walls as possible.

I don't know very much about the Nissan blocks at all....Sorry...

Now with that being said...I'd assume however, that a closed deck Iron block could be bored out far more than a Stock B series block...and still be safe.

 

arent all sleeves iron anyways?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by igotyofire &raquo;</TD></TR><TR><TD CLASS="quote">arent all sleeves iron anyways?</TD></TR></TABLE>

yeah but iron BLOCKS have no sleeves. its the block itself being bored. which means if it cracks teh block is no good. aluminium motors, like b series and ls1's (GM) have iron sleeves that is independent of the block itself.