What is a safe valve to valve clearance? The only info I could find was for harleys and that say .060" which seems to be excessive. The only other info I could find was on endyne's website, and he says .030".
Any one care to chime in?

 

It really depends on your valve stem to guide clearance, and how well you trust your valve springs. 0.030" should be fine with fresh guides and good springs.

 

The valve guides were cut flush. When the head was ported how much extra clearance would you recommend?

 

if the guides were cut flush then the valve job isnt going to last and your probably gona crack the guide unless it was spotfaced... flush isnt good

normally id say 0.030, but w/cut up guides id be a little safer on it.

what cams/valves do you have?

 

Cams are M24x and valves are SI stainless

 

are they over size?

 

No they are standard size valves

 

i have heard of .012 on more radical cams but i dont think that is at 0,0.

 

Listen to Jdogg.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by no2psi &raquo;</TD></TR><TR><TD CLASS="quote">The valve guides were cut flush. When the head was ported how much extra clearance would you recommend? </TD></TR></TABLE>

If the guides have been cut flush with the roof of the port, you will need to allow more clearance during assembly. Exactly how much more will depend on how long you plan to run the head before inspecting the valve guides and valve stems for wear.

Keep in mind that the whole point of measuring valve to valve clearance is to prevent the intake valve and exhaust valve heads from contacting each other during the "overlap" period of your cams; and more specifically between the 335 and 355 degree range [for most cams].

Valve to valve clearance does not affect, nor is affected by, "Spot facing" of the head. Spot facing is used to adjust piston to head clearance.

 

im not talking about spot facing the chambers, but spotfacing the guides..

im talking about the method that is used to cut the guides down, if they are ground at an angle flush with the port there will be very uneven and severe pressure/wear on the guide and the valve, this will crack the guide. however, if you spotface the guide the wear will be even and you wont risk breaking the guide, however you still have the problem of the valve job not lasting as long as a full guide.

with stock size valves i doubt you have anything to worry about.

 

Thanks for the input gents. I am going to degree them and leave it alone.
I update later with dyno figures.