Deshrouding necesary for 84.5mm block and b16 head?

I am looking at sleeving and boring to 84.5 mm. I have noticed that some people have their combustion chambers expanded (I believe they call it “deshrouding”). Is this necessary? Either way, what are the benefits of it over just leaving the chambers stock?

Thanks for any answers in advance.

enhanced combustion process.

hahah sounds like a good answer huh? its something u should do but don’t have too… leaving the head stock bore will give basically higher compression vs a head that has its chambers opened up to 84.5mm. Dan’s ( g2guru) head isn’t opened up to 85mm

Deshrouding usually refers to opening up the areas surrounding the valves. Whether or not match to chamber to the cylinder bore depends on who you ask; ie. Mr. Alaniz and Mr. Widmer stand at opposite ends on this issue. Talk to your head porter…


Ok, I was talking more about opening the actual combustion chamber. I’ll talk with some of the shops around here (there really aren’t any) and see what I can do, but as long as I know it isn’t going to kill me, then it’s a relief.