Currently porting my heads. Few questions:

Intake Port:
On the long side, after the initial curve/turn/radius just after the pushrod pinch area...should I make it straight all the way to the pocket? There is another "turn" that goes "out" back away from the port to the side of the pocket. Do I grind or remove that turn to where its straight all the way from the intial curve?

Short side radius:
This didn't take but about 30 seconds on each one... intake or exhaust. Should I grind more out? Didn't do much.

Exhaust:
I'm going to get some new header gaskets and match...leaving it unmatched at the bottom of the port to guard against reversion. Other than that...how much do I take out of the pocket and port??? The exhaust is weak on this head. Just "cleaning" and increasing the area around the valve guide boss isn't taking out a lot. I'm wondering where all of this extra flow will come from since I haven't done much. Reckon I'll go read some posts, books, mags for a hundreth time to try and figure it out.

Additionally, I don't recommend the Sears Electric Grinder that costs about $100. No trigger to let off when the bit decides to bounce around everywhere, and you've got to pull it out. I already took it back once when somehow the nut that holds the carbide in place somehow was tight enough that the "button" you push to hold it while you turn your wrench broke. The new one I got vibrates every bit I use unitl I get it in the port and up against something. The grinder isn't "aligned" or something. The bits are straight, but you can't tell from the way it spins in free air.

I bought the tool to do my on screw in studs and pull out the press in. That thing wasn't worth a ....

 

Smith,

From what I've been told, the '083 castings used the same mold cores as the '416 castings, except for the top mold which was altered for center-bolt rocker covers. I've never had a set of '083s to compare, so I'm only relaying what I've read/heard.

If that's true, then you can use the attached graphic to create templates that will guid you to safe limts of port enlargement. Copy the graphic and scale it with an editor so the 6" scale is the correct size when printed. Once the size is correct, make card stock tempplates from the patterns and check your porting work so far. If the mold cores were not shifted when your heads were cast, you may be able to open the ports a little more and still have adequate strength and wall thickness for prolonged street use. The net port volume from those templates is 177/64cc with 1.94/1.50 valves installed.

 

Thanks for the templates...answers a lot of questions.

 

Just remember that those are from '416 heads, and I've nver personally verified that the '083s are the same casting.

 

If you bought the Pro Form one, I made that mistake too. Then I got the Comp Cams one and it works great.

 

Well, I have both sets of heads. I'll do a comparison when I check my porting with these templates.

Yep...that's the one I bought. Just bought quite a few ProForm tools including push rod length checker and a valve height micrometer. Hope their usefulness is better.

 

I bought that POS too. It worked fine with some washers to remove the studs. However, when trying to use the arbor to align for tapping... it doesn't align. WHich reminds me, I have to call them back on this POS.