I want to cut my afr's a little more and our bridgeports at work are old as hell

and if i want to use the cnc's my boss will prob charge me machine time around $90 a hr so that is out

so i want to set them up in the wet grinder and just grind off the .015 i want to take off them

but will that be too smooth for the gasket to seal? i run cometics and i think the smoother the better with them just wondering what the thoughts are on this

thanks
mike

 

there is no such thing as too smooth. its the imperfections like scratches or gouges that create the leaks.

 

You want to run between 20-30 RA (Cometic requires a finish better than 50 RA)

Shane

 

Talk to Cometic directly. Flatness is as important, I think it is 0.001 runout over the width and slightly more over the length. My AR's had 0.0005 over the length.

 

ok thanks guy's. a guy at work told me that if it was too smooth the gasket would not hold onto the head and push out.

kind of made sense but really i can't see that happening i think the main cause of failure would be from imperfections on the surface causing a leak .

off to the grinder they go

 

I believe cometic specifies not to cut them too fine, check their website.

 

its going to have to be done correctly for the cometics to seal up.
good advice from shane above.

i worked my setup around a stock head gasket, because i didnt want any issues.