hey guys, i've got a Q here, i tried to use the search but its not working right now. i've got a b16a head i'm gonna pull apart pretty soon to replace some valves, and i'd like to mill the head a bit to increase the compression ratio. the setup i'm running is a fresh rebuilt COMPLETELY stock b16a bottom end, and the head only has skunk TI retainers and dual valve springs, and i'm removing supertec (not oversize) valves, and probly replacing with the same, or similar (not oversize). my cams are stock, but i could possibly have plans to replace with ITR or CTR cams, so that could be a possible factor as well. also would be running a 2-layer head gasket with this setup once done. my question is, how much can i safely mill the head, considering i'd still like to have a small amount of safe cam adjustment if possible. i'm not expecting any HUGE gains with this, but i just figured its something i can do in the process before i put it back together.

 

bump, someones gotta know

 

bump

 

OMG, someone out there has to know this. wheres all the genius/gurus when you need them???

 

I milled my b16 head .30 and shouldn't have any problems until I miss shift..

I would leave it stock and get a thinner head gasket.

 

mine is also .30 over and never had any probs

 

well, with .20 over i can get over 11:1 right now, and thats what i was shooting for.

 

.040 off and plenty of space even with JUN type 3 cams on top of a 13.2 comp block.

Rumor in the engine building crowd says on certain builds you can take up to .050 - .055 off and be "safe" but we always recommend to clay and measure thoroughly to figure out the exact clearances of the motor before you mill just to get an understanding of the amount of room you have to work with in there.

Also dont forget that milling the head WILL retard your camshaft timing as well...i see people overlook this a lot doing their own assemblies!

 

i didnt know that mastarolla, could you explain a little on why that is

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tegman85 &raquo;</TD></TR><TR><TD CLASS="quote">i didnt know that mastarolla, could you explain a little on why that is</TD></TR></TABLE>

yes, please explain if you have the capacity to do so. anyone else heard of/confirm this?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tegman85 &raquo;</TD></TR><TR><TD CLASS="quote">i didnt know that mastarolla, could you explain a little on why that is</TD></TR></TABLE>

Im assuming youre speaking of the camshaft timing?

When you mill a head from an overhead cam engine you are now bringing the valves closer to the piston during the timing events. In other words you are brining your timing sprockets for the crankshaft and the cams closer to each other. Advancing the camshaft will pull the timing events back to their proper position however the only way to be 100% accurate on EXACTLY how much advance is needed is to degree the camshafts.

On the Jun 3 engine i mentioned i had to advance about 2 degrees to regain the proper timing.

Hopefully this clarified

 

i see what u mean now. thanks for the insight