Thought I'd share my progress on my heads. I did this mostly as an experiment and it's been going pretty good. Picked up a set of aluminum heads for my supra. I have a cc306 with the supporting valvetrain ready to go in. But I wanted to try and improve air flow a bit. This car is basically the most extreme budget build and I'm cutting all cost to a minimum where possible. I'll be resurfacing the heads and doing a minor port and polish job on the heads. I'll do the bowls where the valves are and the runners. Here's my progress so far. Criticism welcome....

 

very nice, looks pretty good, i would watch out with the smooth texture, air/fuel mix likes to separate when the runners or bowls are polished, at least thats what i have read from my research, i am doing the same as you, i have a set of heads off a 96 lt1, havent started grinding as i am getting together all the necessary measuring tools. i would ensure at least that the combustion chambers all have the same ccs,

a good way to check is to use a peice of plexi glass with a small hole drilled in it, use vaseline around the combustion chamber as a "seal" and use a baby syringe with ml on it, 1ml=1cc. fill it with water and ull know, not sure what kind of tolerance is acceptable, i just know if you have a cc variance it will mess with how the engine runs. not sure how important this is, if someone else could verify thatd b good because ill be in the same boat as well

 

what are you using for the project? how are you going to get down the runners? i am using a dremel 3000 for the chamber and probly gonna get an electric die grinder for the runners, but like i said im not quite there yet

 

FWIW,, I have a friend that used to port heads,, (Retired now) He had big name clients in Indy, Nascar etc.. He told me that if you simply clean up around the guides, and take the sharp edges off chambers and in the runners, nothing fancy,, your at about 90% of whats available to be gotten. A good 5 angle valve job bought more power on most heads than the fussier porting did. In other words its easy to spend too much time on it. His theory was that its easier to drop weight off the car than port,,, Now that being said, they did spend the time when it was a $150K + engine package..

 

Huh that is pretty cool, so the cc varience isnt as much of a problem as I had thought? Good info I'd listen to him over me I have no experience, just research, any other tips ur buddy shared with u?

 

Thanks guys. I'm using a combination of a drill and a die grinder. I'm not planning on getting too invloved with the runners. I'll smooth out what I can get to and open up the ports a bit but I don't want to go overboard. I'm not a professionaland don't want to do damage. Lol

 

Looks like it's coming along. I never PP'd my heads but I did my PP and match my intake and intake runners. Used one of these and lots of flap wheels.


+ lots of time and patience.

 

Cleaning up bowl work, un shrouding the valves is not as detrimental as going into the runners, if you dont know what you are doing in this area, you can scrap a set of heads quick, people tend to hog out the radius and this is the wrong thing to do...

 

^^^^^^^^this^^^^^^^^^
Lots of epoxy or recycle that aluminum

 

The most critical areas are the valve seats, the first inch above & below them, and the short side radius. I have had many home ported heads across my flow bench that flowed no better & often less that stock castings with the correct valve job. And, the corner automotive machine shop's valve job for an engine overhaul is not the correct valve job for making hp. That, and how the area is shaped on each side of the valve job. Also, intake-to-cylinder head port matching. There are wrong ways to do that as well, that will slow your car done. The floor-to-wall corner radius is important too.
Amature head work, no matter how smooth & pretty, often costs power, slows the car down.
Not going to name names, there was a pattern, when I had my dyno, of who's heads (I saw mentioned on message boards a lot) made power, and who's typically did not.
When I read a car's info before tuning it, I usually had a pretty good idea if it was going to make any power. Self ported heads just about never did. Makes more difference if the engine is NA.
Lloyd Elliot's stuff appeared to be good. Saw a lot of his.

 

1000% true.

I brought a book and dvd off ebay way back in the day. Informative stuff but always clear on how easy it is to screw up a good set of heads if you're not careful. Practice on those junk yard heads and flow test them till you get it right and are making progress. Porting and Polishing is an art work.

 

Yeah, just to clarify. I'm not doing anything major. Just smoothing out the ridge around the spark plug hole and a few other areas. I'm not going too in depth with this just barely making a difference if anything.

 

Don't get discouraged take your time and make your car what you want it to be. Just research it well and learn the trade. If I was doing my own heads I would be all up in those bowls and runners but I would make sure I did it to spec and have the heads flow checked. That's part of what makes building a car enjoyable. Doing stuff yourself.

In all the years I've been working on cars half the stuff people tried to discourage me about doing were things they themselves were just not confident about doing. Best thing I ever did was not listen to anyone and learn how to do the technical things I really wanted to do myself. While other guys have to look for engine builders and transmissions builders they're just things I can do myself confidently now because I took the chance on making mistakes to learn how to do it correctly. That's just the approach you have to have with these things. I don't know who makes books or dvd's on head porting it was years ago for me but the stuff is out there to learn from.