ok so im porting and polishing my first set of heads and was curious how important is it to make sure all intake ports and all exhaust ports are the same volume? i know cumbustion chambers would be really important but what about ports, ive done the same thing to all of them and i highly doubt they are more then 5ccs difference from the smallest to biggest(im guessing more like 2ccs but im trying to be conservative) i was smoothing out the combustion chambers, all the port walls(along with enlarging the centers where its the smallest) making sure theres no sharp edges anywhere and trimming down the valve guide bosses(and the valve cover boss at the entrance of the intake ports) basically all the beggining stuff they are 416 heads for a 305 and im going to be using a lunati voodoo 60103lk? cam set iirc(its the 1800-6200 rpm one)

 

Well, think of it like this...

The factory just cast them, ran them through a couple of machines, and bolted them up; and millions and millions of cars go through their entire lives from cradle to grave just like that.

So it's not "important" in the sense of, whether it will survive or anything like that.

On the other hand, if you want the motor to run PERFECT, like you're in a class where everybody has the EXACT same parts, and winning or losing comes down to how perfectly you get everything set up and maxed out, then maybe it matters.

For a street motor, it's probably not going to make a detectable difference. Probably 90% of the actual benefit of porting, is the part right near the valve guide and the throat, which don't affect the volume that much anyway.

 

yep, i think it will only matter if your looking to make as much power as possible so you would want all the ports near identical in air volume, flow capabilities and velocity.

On a street car with that cam as long as you feel you did about the same amount of work to each port, it should be fine

But you could make some templates to check to see the differences of each port. Get something of a known length/width and go thru each port to see if any one looks noticeably different and such

 

That's a slick combo. I had that cam with my ported 416's on my 350 briefly.
As long as the ports are eyeball similar you're laughing. Get good at using the plexi plate and burette if you want to be sure.

 

yah im going to have em shaved down a little bit like .010 doubt it will make much difference in compression but hey it will prob equal itself out when you figure in the chamber smoothing. its going to be a street/strip car thats only drove mayby 1k-2k miles a year and its also going to have a 200 shot of nos on a progressive controller, i should be good to go with that, they all look the same eyeball wise