416 castings verse a set of 081 that are ported and polished. which are the better castings?

 

I've done the 416's with good results.
Others have done just as well with the 081/083 heads
The centerbolt heds have a better spark plug placement
reaches into the chamber a lil farther.
Both seam to have the same ports
Which is better is really a toss-up
I'd work with which ever came along first

look for flow figures around 240+ cfm in and 180+ exhaust
with 1.94x01.60 valves and max home porting.

 

They're about the same. 416 are perimeter bolt, 081 are centerbolt and have th elater model style intake bolt holes.

 

I ported the hell out of my 081 its amazing how much you can actually take out of the intake ports and how much you can open the exhaust ports on these heads

 

Yes as long a s the casting does not have bad core shift
you almost can't screw up ( break through)....
Lots of meat there

 

If you break through can you use epoxy to fix it. I havent done this just curious if there is fix for it

 

yeah tell me about it. I was grinding away at mine when.....oops....I'm not supposed to see through there am I?!!! Real bad core shift on one of mine. But the other was just fine. I got another 416 for practically nothing.

 

Really I didnt break through just wondering if there was afix for it without getting another head lol

 

You can repair a intake port with epoxy putty,
and an exhaust port with "Thermo-Steel".

Thermo-Steel is made of the same stuff as Muffler Cement
but with iron fileings mixed in. 2400*F,,, neet stuff.

http://www.cargochemical.com/main.htm