Never said that either.
Where does someone just begin? You can't just dive in with a grinder and hog the snot out of them. If you do them "right" all should be good, but how do you know they are "right"? I understand what your saying about learning, which is all good. BUT, where do you get the info to do it right? Videos? A book? I suppose trial and error is good, if you have deep pockets. Ya gotta be careful of the internet also, it just full of wonderful info, if you can decipher what is good and what is bad.
I am not trying to argue with you and I don't want to sound negative. All I am saying is that a person can't go in and "just grind". What would be great is if someone who knows anything could help a guy out and I'm sure thats how most head porters start.

 

http://www.sa-motorsports.com/diyport.aspx

Here's a good started DIY article, they cover some of the basics.
Certainly won't make you a master machinist, but it's a start.

Biggest mistakes I see people make are
1) Porting out to the size of a gasket when the purshrod pinch is the biggest restriction.
The resulting "baloon" kills velocity.
2) Cutting too much out of the short side of the curve
3) Too much emphasis on flowbench numbers at .650+ lift when the application only requires .550-600
4) Not using a template for uniformity in the combustion chamber and intake/exhaust ports.
Some of the chamber work I see (even from bigger shops) scares me.
Making up for poor design by advancing timing is not as good of an idea as some may tend to think.

and the worst of all

5) A poorly-done valve job.

 

Maybe a little backround would help.
94zgreenmachine had a well liked "professional" do the work he talked about in post number 13. Once he realized his mistake he sold that stuff and bought good parts, he is trying to tell 78Z28350 not to repeat his mistake.

 

It really all depends upon one's perspective. If you have the aptitude, the time, the tools and the desire work on engines then by all means go for it. On the other hand, if you want to get it done quickly so that you can ge behind the wheel rather than under the hood, you have someone whose job and expertise will put you in the driver's seat do it.

The oringinal owner paid to get the high-performing car to begin with, rather than start with an idea and build one. When the car wasn't fast enough for him or a subsequent owner, the choices are to DIY or have someone else do it. It's perfectly reasonable to opt for either choice. It all depends on your preference. Just because one chooses to have a pro do the work doesn't mean that they couldn't do a good job themselves. It just might mean that working on cars is not on the top of the their bucket list.

 

I've done dozens of heads from 2-strokes to old honda 1200's and most every one of my personal cars (AMC, Chev, Caddy) that I tore into the engines.
NEVER used a flowbench because i never could afford it and didn't HOG anyone of them out. (common sense here.. more does NOT mean better flow)

I just read a couple of Chev high perf mag stories and what Smokey said to do and just 'cleaned up' the casting some and smoothed out the floor, sides, radiused the corners some, gasket matched the first 1/2" in or out.
Kinda like pickin your nose, You wouldn't think that little bugger could cause so much restriction.. Just smooth things out, don't get too energetic (you wouldn't with your finger...)
And the 'average joe' won't see much past 5500rpms and your cam is restricted itself.
OH, and just think that a GOOD 3 or 5 angle valve job that's lapped in will make a world of difference with just that!
Now with that perspective, I've seen some coreshift heads that I thought, MAN, how could this have run well at all? GM doesn't port thier heads from the factory to the general public and you would think the performance is good.. (I know.. I know, the casting tecniques have gotten lots better)

What I've found is that you will notice smoother transitions from off idle to hwy driving.
IMHO, I'd just clean up the ports under the valve by smoothing out rough corners/edges and port match the gaskets 1/2" in. and pay for a "good" valvejob and bolt them on and have fun.

Oh and while the heads are off, get the injectors flowed by Marren or RCI (about 25.ea)
Just my .75
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