Well after weeks of exhaustive research, I finally spent the day out in the shop, porting my heads. Got a pretty good start, basically hogging out the majority of the material I planned to remove. I still need to do the finish work but heres some random pics from this afternoon:

Before:




After:





These pics are pretty representative of all the chambers. If anyone has any suggestions or observations give me a shout, I'm all ears

 

round off the corners of the spark plug boss, and smooth away the sides of the chambers that surround the sides of the valves a little bit to promote an "open chamber" effect.

 

try trimming around the valve guide more. your on the right track on the ex side . hard to explain better if you see a good port job.
there is a good article on cylinder head porting in the fall 2009 issue
of the engine masters magazinevol 12 no3 issue. Also finde a good machine shop that does racing engines as they could do a trick valve job.they could
use a radius onthe ex and put some good angles on the int.
and take another radius type cutter to un shroud the valves and blend
into your top angle.you can gain good amount of flow from a good vj

hope this helps if you have any more questions be glad to help!!! shane

 

cool

 

Put a used set of plugs in the head to protect the threads and make sure you do not remove material that will expose the sparkplg threads as well.

 

this is where I'd be working... you know what looks like it will flow air, and I do a lot of "fingering" of the ports to make sure they also feel like they will flow.

 

Some in the know out there may critique as threads like this can be "blind leading blind" because there are so many things to consider.
BUT...if youre dead set on doing it.....this certainly wont hurt.



Blend in lip between valve seat and bowl, neck guide down (no need to get crazy not taht much to be gained there), walls of the bowl can be taken out some (more is not better), roof of port can stand a little work. Sligth deburr on the spark plug thread end, wouldnt worry much about unshrouding if you havent done it before leave it alone. For the most part you can smooth the chamber out, clean up any lip between the chamber and seat and call it a day there. Removing material means doing this much differently and having to CC/mill the heads dont go there now. Pushrod pinch area you can work some, blend it in so its a nice gentle bend into the intake port. Dont go nuts on these heads theres not a whole bunch of material there, if you area patient you could probably squeeze 220-230 cfm out of the intake port. Exhaust similar things, roof of the port, some off the sides. The short turn you want a nice smoth bend on it. Dont worry about removing a bunch of material the water jackets creep up close there, dont lower the floor.
Keep your grinder speed low, dont overheat your carbide. If youre not brave with a bit you can use some 40 -60 grit rolls and help it along some. The guide bosses will require patience and are a PITA. If you nick a valve seat most the time they are fixable.

In short, you shouldnt attempt any of it really. The above stuff can be considered inaccurate because there are so many things left out and many other variables. But because you are then go to town anyway. What the hell.

 

What the hell indeed!

Seriously though, thanks for the comments and suggestions. I will be using these heads on my home ported crossfire project, and am sticking to doing it myself. I can't tell you how many times people have told me not to try this myself, how do you get good at something unless you do it yourself!!

 

Everything you are saying is is good info.Also as were the previous post.
I do this everyday ,gonna grind some iron eagle's hopefully later this week . Do not think anyone gave any bad info here.Not sure why you might have thought so.I do not think anyone is looking to bash your work.I am certainly not ,as i could tell you where you could give them a little more tikling.But who ever ported those did a fine job.That was a great eaxample of a ex port. I do not care what anyone tells you
a good valve job is very inportant!!Anyone who does performance cylinder head work will tell you that.There is good gain there alone with out the port job.
Nothing was left out i told him where he could get great info.Every thing he needs to know is right there in the article.Not sure what was wrong
with that.If you pm me and give me your address i will send the magazine to you .And you will be happy with the info and pictures.If you get some old sbc valves you can drop them in the guides and grind around
the seat without damadge.Also line up the gasket on the deck surface of the head and scribe your self a line around the chamber.Do not open
that up more than needed,do grind out side your line leave some material there if you are going to attemp it.What the hell you can do it
just be paitent.If you don't atempt it you will never learn!!!


good luck!!!!

 

engine guy the exh port was off a set of LT1s I just finished for a member here.

 

Like i said earlier good job.

 

 

Cuisinartvette (Ron) does some nice work on cylinder heads. He is very talented. I have tried it and done it for years, and it really is harder than it looks. But I know how far I will go with it. My rule of thumb is the better it is to start with, the less you mess with it.

 

No expert here (2 sets, 25 years apart), but here's a few pics from my 86 128 heads. My goal was to make them more efficient, not larger port volume. You can see from these pics that there can be a lot of work in the bowls, to clean up the cast to machining, transitions.
I went to 80 grit in the intake runners and down to scotchbrite on the exhaust.
I also took the chambers, all the way to scothbrite.

Ron was kind enough to send me some of his sanding rolls, thanks again Ron.

 

Nice looking job Agent! Thanks for the pics. I'm on the way back out to the shop to get after it for a few more hours, more pics tonite.

 

Make sure and use good eye protection (dont wipe your eyes either when working ), dust mask isnt a bad idea. One shaving can ruin your day!

Good lighting helps, getting some in the port youre working on even better. Harbor Freight sells some very skinny/small flouresent type lights you can stick in the other end it helps a bunch. get a few, they are cheap and dont last that long lol.

 

good job agent...how much did you gained with this heads?i also have an 1986 corvette and i would like to do some tuning..hehe..

 

Sorry, no idea. They were part of my budget 355 build.

 

Couple pics from mine if some more can help, they flowed 235 at .500, 40 more then stock but still not great.

 

Ugh...I did some work on the heads today and my grinder pooped out on me. What brand of air die grinders are you guys using? I need a replacement.