anton_

hello.
i lifted the cylinder head just to se how the pistons were doing after a summer, i bought the wrong pistons, i got b18 pistons instead of b16, i got 7,8-8,0 in comp.
i could go with 21 degrees at 20 psi and 8500 rpm and making 360 whp

i had to use a comtic headgasket .04 thick because the piston was out of the hole a little bit.

what do you think, should i buy a cometic again or should i mill the pistons own a little bit, so they dont stick out of the cylinder.

DaveF

it would be less time consuming to just throw another gasket on there.

yakuza

Or get new set of pistons and the right ones this time and while at it you might want to get 9:1 CR pistons. Help you obtain that 360hp at less boost.

onefstek

you have a few options.

thicker head gasket
mill the pistons
mill and bore the big end of the rods

Turbo-LS

iTrader: (4)

How much are they coming out of the top of the block? I purchased ls piston/rods but for some reason i got gsr's. they come up out of the block but only a third of the thickness of the headgasket so clearence hasnt been an issue and it bumped my compression up higher which i liked..

Bring the piston to TDC and measure how much your piston is out of the hole and go from there. other than that i see no need to tear down the bottom end when there are different thickness gaskets to be had

I believe mine stuck out .018 and stock gasket is somethign like .028 or 0.30. Dave correct me on that if im wrong

DaveF

i belive the oem gasket thickness is 37 tho. and piston to head called for 45 thou. dont quote me on that though. lol

anton_

hard to messure, but i came up with 0.01" when i tilt the piston against the cylinder wall and messure were the piston is most out of the block,

matt k

all the shelf pistons have the same pin hight 12.1 9.1 it dosent matter b18c/b16a/b18a they are all the same pin height i know all the je pistons stick out of the hole on a b16 i use a 51tho head gasket and call it a day

yakuza

OEM HG thickness is 0.030 ...

HiProfile

Those are Wiseco pistons, and they use the same piston part # for b16/b18b/b18c motors. The compression is just different based on stroke and head. Unfortunately, they require a .040" thick HG due to having one-size-fits-all pistons (that's why they're relatively cheap).

You could mill them down, since there's more than enough material to remove just .010" to run the stock HG safely. I wouldn't worry about valve reliefs unless you run huge cam lobes. I would be very careful how they get clamped down when they get milled. They are very sensitive due to such small clearances. They also have sloped skirts, which means using a lathe requires a incredibly delicate touch.

UK Accord

Both sets of Wiseco Pistons I have had for my F22 Z2 have sat 1mm out of the deck.

Both sets I milled down 1mm and had no issues.