cylinder walls
cylinder walls
first off im new here and like to say whats up to the folks here at NICO, lots of good information on this board. Im a ex-porsche (multiple 944 turbos) driver but as funding went down ive come to nissan as my rear drive platform car, anyways. My question is this, I want to build my s14 for turbo and I am going to be changing a few things on the block before i boost her. I want to put new forged stock bore low compressions pistons in it but I was wondering if i put them on my motor that has 140k on it with a hone, will it be a tight fit or are the cylinders walls possibly worn to a point that boring over would be good for a nice seal. I do all my work in my shop but i really dont want to take the block out and send it to a machine shop, you think new pistons and a hone will suffice?
As a rule, I personally think it's best to just bore and hone for some small overbore pistons...such as .020 over. It assures you a fresh surface but also isn't enough to really matter as far as future cylinder wall thickness issues go. There is also still room for ANOTHER .020 overbore if it is ever warranted. At the same time though, my 120k motor had absolutely no noticeable wear in the bores, no step at the top or anything. I think if the bores had been standard size, I could have just honed for the new rings and been fine 
You'll have to also see what size bores you have, Nissan has either 3 or 5 grades for them, and that could make a difference in the exact size pistons you would need to order The bore size is stamped next to each cylinder on the top of the block.
You'll have to also see what size bores you have, Nissan has either 3 or 5 grades for them, and that could make a difference in the exact size pistons you would need to order The bore size is stamped next to each cylinder on the top of the block.
Back to the drawing boards for me.