Hi guys, I am need of info (done plenty of searching to reach no success) As many ppl have, I have switched my build up many many many times in the past 6 months. The current route I am sticking to is: JDM B18C BLOCK,ACL main,rods and thrust,stock b18c1 crank,girdle,pick up,and windage. Eagle rods,obd2 ITR oil and OBD1 water pump. Mostly oem, the head has JUN springs,retainers, stock ITR valves ,and JUN3 cams. My current area of concern is pistons, I need a piston with 11.5 cr or more for my cams. A machine shop will be assembling my motor for me as i do not have the knowledge,time,or space to do it myself. Should I be worried about piston to valve contact,they are a very reputable machine shop in my state.My bud with a similar set up made 231,so i am hope for 230+ or more. Does anyone have a piston reccomendation for this build? Thanks in advance!

 

If your machine shop is a reputable one, they should be able to provide you with the best suggestion on what will work for your build.

 

Look into the jdm p30 or jdm p73 piston. I think they might get you where you want to be.
I would definitely check clearances when using any non oem cam with adjustable cam gears in various positions. This will let you know how much you can adjust your gears and still maintain a safe PTV clearance (.040" is usually considered a safe clearance).

 

Do you think there is a a P30 piston with 12:1 and floating wrist pin design?

 

I don't believe any OEM piston is floating pin. From what I've seen all OEM rod and piston combos are pressed pin.

 

My rods are aftermarket.

 

And the P30 is an OEM Piston...... Won't work with any floating pin rods. You will have to get aftermarket pistons in whatever configuration you are after.

I thought my answer was pretty clear. OEM is pressed pin. Aftermarket can be either pressed or floating, so you have to make sure the piston and rod match in style.

You could get the OEM piston machined to accept wrist pin locking spirals. Would likely need to be rebalanced though.