Porting heads how hard?

[tparker]

OK, any one can take a die grinder and go to town, but how hard is it to do a decent job porting heads yourself? I had an old 383 in high school I "ported" But they were never installed on anything so who knows if I actually made it worse. LOL. I have been watching and reading a bit about stock 340 J heads and aluminum ones as well as other heads and have seen many claims. I am sorta considering doing some work to mine at some point in the future and just curious if it would be a complete train wreck to do it myself since I haven't actually done one before.  The next question is should I even bother and just buy different heads.

[Mr Cuda]

 Many a head have been ruined by porting.
Porting is easy, just grind away,  and make it big.
So, port match intake,  no more than an 1" in, hopefully less.
Don't port match exhaust, just remove flash from sides and top. Do not touch the bottom.
Valve bowl can be  blended  to the guide.  That's it.

[pschlosser]

Not knowing when to STOP grinding is often to blame for ruined heads.  If you're conservative, you don't need to stress out about it too much. 

Often, any porting is an improvement on stock OEM heads.  But a head shop will do a superior job than your typical DIY-er.  And if you're porting expensive newish aluminum heads, you may be taking quite a risk doing it yourself.  In the latter case, I recommend going with a shop.

If these head are common and not all that valuable and/or if you're thinking about buying new heads down the road, I say go for it, research, learn and give it a go.

[HP2]

If these are original Mopar heads, there are templates kits out there for B/RB, Magnum, and LA high swirl heads that can take all the guess work out of it and have been proven by the factory  to improve horsepower. If you are messing with aftermarket heads, then it would probably be best to talk to the manufacturer about what they recommend.

I have read  an article that the biggest gains are in the throat to valve guide transition area and a deep cut into this area when having the guides done, can yield about 60-70 percent of the overall porting gains. However, a shop highly knowledgeable of Mopar heads would be needed to pull this off.