overbored pistons + shaved head

[StorminNorman]

I overbored my pistons .040 over and shaved my head .020. Does anyone done something similar. what results did you get . Does anyone know what the max is you can shave the head?

[dickie]

welcome to nico!

im going to move this to the ka forum where you are guaranteed to get some better information. good luck.

[StorminNorman]

here's some pics of the head...,,,,,I port and polished the head and entire intake..........how do you insert pics?
Modified by StorminNorman at 2:57 PM 3/8/2007

[StorminNorman]

Modified by StorminNorman at 7:36 PM 3/8/2007

[StorminNorman]

[StorminNorman]

[240sxmech]

get rid of the butterflys that are in the intake mani and you need a little more gas with your setup.

[StorminNorman]

there is no internal butterflies on thisits an s14

[dickie]

dunno if you knew or not, but youre not supposed to polish the intake side.

[B33FST3W]

dunno if you knew or not, but youre not supposed to polish the intake side.

That is only if you have a carburetor. EFI makes it where the gas stays nice and vaporized

[StorminNorman]

The intake is not polished it was only sanded down with 80 grit. I was told that this was the best grit to promote a higher flow rate.

[sxseguy]

The combined maximum for cylinder head resurfacing and engine block decking is .008 inches. You're way past that already if you've had the head shaved .020".

[neverlift]

I'd say 40 grit to get the swirl effect but I'm no pro... I remember something about polished for boost and swirl for n/a,boost is gonna fil the cylinders anyways,n/a needs turbulance to fill the cylinders....

[StorminNorman]

Its not so much for swirl effect to vaporize the fuel as it is for flow properties of air. Air will flow faster if there is a small amount of drag on the walls. Its like a cushion to ride on..........

[dickie]

youre correct

[neverlift]

yeah I could have worded that better, wasnt trying to say swirl effect(of the air) just the ~look~ why would a 43 psi(or in my case 57) system need vaporization lol, I tried explaining this to my neighbor(15)..... went nowhere quick

btw my bad about turning this into a debate or what not.... I tend to do that... now we cool

[StorminNorman]

It says in the fsm to only take .008 off the head so that it wont affect anything like timming or normal performance. Ive had the motor together with .020 takin of the head. I just had to make sure the timming was set right and it ran great.......

[StorminNorman]

I think I read in here somewhere of some one taking off .030 It would be nice to here of someone experience with this....I'm interested in going more if possible but would like to no off what type off problems people have had doing this.........comments would be great....