Im gettin my f22 head milled .030'' which is what iv heard the maximum is. With that mill Just how much of a gain can i expect in compression? Im running stock pistons and rods.

 

Not sure, but your cam timing will be off. You may need to install an adjustable gear. .030 will retard the cam timing

 

It will gain you approx 0.5:1 - 8.8 up to 9.3.

0.03 off the head is a lot. I would suggest that you clay the engine after removing that much from the head. Make sure that your piston to valve & your your quench (piston to head) clearances won't be compromised.

I am also removing 0.03 from my head but I'm running a thicker head gasket. The reason that I am removing that much isn't for compression gain, it's for a better quench area.

 

okay thank you ghost. ANd yes i know about the timing issue, i got me an adjustable timing gear :D. But question- if your arent removing it for a higher CR, what do you mean about a better quench area? Wouldnt the milling of it decrease your head to piston area? I know increased compression is a great way to generate more power and all, but what exactly does a better quench do? Also with the raise in CR as stated above by ghost, will i be able to safely run a stock bottom end? (pistons, rods, etc.)?

 

Now my reasoning for the 0.03 has more to do with the squish/quench area of the combustion chamber because I am boring my Darton sleeves to 89mm. The diameter of the combustion chamber on the stock F22B2 head is only 85mm. Look at the image below. It is a pic of my F22B2 head. You can see that on this head there is a 0.027mm deep lip around the combustion chamber. It is only 85mm in diameter. It would cause some turbulence if I left this there. By milling the head and removing that 0.27mm deep ridge. I create a larger squish or quench area for my 89mm pistons.



here is a side by side of a Honda single slug cylinder head. It has been worked for a better quench area.



You can see the ridge around the one on the left. Similar to the F22B2. On the right is a head after milling. The ridge is gone and circled in red you can see the flat quench area that has been created. Match this with the flat top of a custom piston and you will be good to go.

Yes it will decrease the clearances. That is why I am using a thicker head gasket. Using different thicknesses of head gaskets will allow you to adjust your P2V & P2H clearances.

Yes.

 

Wow ghost, that was a very informative post. thank you very much. You're probly one of the few members i really trust on this site ha. but thank you very much for the little lesson and info. And thank god, im so relieved i can run my stock bottom end with my new raised compression, Thank you again ghost.