Pictures for elaboration

 

I see the damage, but it's hard to imagine the tune alone caused that. Either way the block is scrap

As for cam, most of Lingenfelters offerings will drive nice and smoothly. And as for your clutch being nasty to drive with. Buy a proper clutch. There is little reason to have a clutch that isnt smooth to drive with these days.

 

The case of this damage was investegated and the following cases came at the same time that made the block to crack:

1.The tunning was not that best, where the tunning was found it is a copy of SD from another car and not optimized with the new combination I have.

2.The engine block is LS1, where the bore was overbored to install new sleeves to acomodate piston size of 4.0845" bore. The recommended interference fit shall be 0.002" per the recommended sleeve (Aluminum to Iron), but the shop made the interference fit of 0.006".

3.The overboring of the block wasn't made at each of the cylinder center point (found offset of almost 3mm).

The block is crap now

 

Didnt realise it had been re-linered.

I know everyone has different views, but I wouldnt trust any re-linered block. Factory installs only as far as liners are concerned for me.