I have a b18c gsr and it's being rebuilt and turboed my tuner said we need to bore to 84mm but I've read that I need to sleeve but he said we don't for our hp goal 360 - 380whp with a great tune now my question will I be fine at 84mm with a really good tune thanks for any info plz no bashing

 

If you're running a stock sleeve GSR (B18c1) block, there's no way without aftermarket sleeves to punch it out to 84mm. The stock sleeves are 81mm - they'll work on boost at 81.5mm (maybe 82mm but i wouldnt advise it) and there's nothing left after that.

I'm not sure why your tuner would suggest needing to be at 84mm for your goals. Would more displacement help, yes. Is it required, no. For 380whp, a simple 81-81.5mm piston/rod build is more than enough. Hell, with E85 and a good tuner (i'm doubting the competency of your current tuner) you could make 380whp on a stock block GSR...

 

Boring to 84mm on stock sleeves is not only a terrible idea (if even possible) but also completely unnecessary. You could meet your goal with a stock b16.

 

He said that the block was crazy worn and just beat to hell and needed over bored and when he said 84mm I got concerned about the stock sleeves he said it would be fine (idk) thanks for the replies

 

If the stock sleeves are worn out of round or have scratches in them (that you can feel with your fingernail), then it will need to be overbored. Provided its a stock 81mm sleeve, it will be fine if bored over 0.5mm to 81.5mm. Should it need more than that, find yourself another block.

Since you have the GSR head, you could easily find an LS block with good cylinders (or good enough to be overbored to 81.5mm) and use that as a starting point - its generally cheaper than rebuilding a GSR block

 

Bore to 81.5mm or sleeve with darton dry sleeve back to 81mm. Darton dry sleeve are very strong. Darton dry sleeve wirh flange are much better...darton mid wet sleeve are overkill for ur setup.

 

Thanks guys for your replies were doing 81.5mm