I have an LS motor in the machine shop and I was wondering what the limits on boring an LS block, its a limit and the machinist wants to bore it out pretty big(.050)since there are something wrong with the cylinder walls.
How much power can I make before I crack a sleeve with a bore like that, I plan on going FI in the future.

 

For boost I wouldn't go more than 81.5mm

 

I agree, with stock sleeves no more than a standard .5 overbore. If you get it sleeved then 85 is the max.

 

Like everyone else said. 81.50 is the limit with boost IMO. You will see how thin the sleeves get at 81.50

 

^ yup

 

If he's actually talking about going .050" over, slap him. That's a 1.25mm overbore, and I don't know if the cylinders would stay round with an all motor application.

 

You can make 600+whp on a 81.5mm bore as long as your tune is good.

 

not giving you any ideas but we had a 84mm stock sleeve ls that was boosted for a bit just had block filler in about the first inch of the water jacket..... we ended up spinning a bearing


Modified by taggart_lumpy at 2:41 AM 3/3/2007

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by taggart_lumpy &raquo;</TD></TR><TR><TD CLASS="quote">not giving you any ideas but we had a 84mm stock sleeve ls that was boosted for a bit just had block filler in about the first inch of the water jacket..... we ended up spinning bearing</TD></TR></TABLE>

B20? If not do you have pictures?

 

81.5 is what mine would be if its .050 over? also, how big will my motor be then?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by efKART &raquo;</TD></TR><TR><TD CLASS="quote">81.5 is what mine would be if its .050 over? also, how big will my motor be then?</TD></TR></TABLE> .020=81.5mm which will still be a 1.86L


Modified by SynTeg at 9:03 AM 2/27/2007

 

get a new block if it needs to be bored that much

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by efKART &raquo;</TD></TR><TR><TD CLASS="quote">81.5 is what mine would be if its .050 over? </TD></TR></TABLE>

no as mentioned above... .050 inches = 1.25mm. so your motor would have a 82.25mm bore which is too big on stock sleeves. if you need to go more than .020 inches or .5mm than you should just go ahead and resleeve the whole motor.

 

no pics but i promise its one of the weirdest things youve ever seen