Wasn't trying to flame you Grease, just wanted to put you on the spot about your assumptions. To see if you could support them. I don't know what the rest of your package was, the cam I'm running is what most people on here call tiny. Could be that you had a large enough stick that a set of heads in the 230cfm range would choke it down terribly. I don't see the problem with ironing out reasonable expectations and comparison methods. That can only happen through disagreement, debate etc.

Kevin, right on man. I assume everyone does this stuff for the enjoyment. If letting someone else handle the challenge of the more technical stuff makes them happy then woo hoo! Fine with me. Ive always done my own stuff and producing world beating results is not one of my criteria. The satisfaction of having a project come together well that you did yourself is very sweet indeed. If it doesn't wind up quite like you imagined then back to the drawing board

I will be posting quarter mile data in a couple months when it's running and the tuning is sorted out.

 

 

When I went to port my heads, I emersed myself in it. I talked to different pro porters and DIYourselfers to get advice on what to do. I researched this board and examined several ported heads in person and examined countless pictures of portwork. I was die hard meticulous once I actually ported my own heads. I was quite proud of them and they made good power. About six months later, I popped a head gasket with a 200shot and decided to have a pro look over the heads and make improvments that an experienced hand could only do. He improved the flow numbers and it reflected in alot more power. More importantly he took the time to show me exactly what he did , so that when I port my next set of heads I can further refine my own portwork.

If everyone just paid the current pros to port heads, where will the future porters come from?

 

Future porters come from guys that hire on at a porting shop sweeping floors and work there way up after many years to be a head porter.
Don't think that just because ya can grind and make um look reasonable that ya are a head porter.
Just like welding,just cause ya can burn a rod don't make ya a welder. Would you weld together a roll cage for your car if it was an 8 sec car and ya only practiced for a week with a welding machine. If ya do/would you are a damn fool.

 

In the voice of Hulk Hogan AMEN BRUTHAA






There are certain things in this world that you CANNOT shortcut the learning curve, head porting being one of them.


David

 

From the forum user agreement:

 

[QUOTE=grammerman -It's curious that AI or anybody else could modify the floor of the port to fix your intake port and wind up with the exact same runner volume it had before they started grinding [/QUOTE]

I know ya haven't been at this for a long time,that's evident, but have ya EVER heard of Epoxy.

Experienced porters can use the floor to open up and Epoxy to fill in the messed up parts and come out with the same CSA.

 

Its easy to see why you end up in arguments in most of your threads. Now you're violating forum guidelines by arguing with a moderator in a thread. Guidelines suggest that you have a problem with a moderator and his actions, you take it up in a PM, and not in a response to a thread.

And, then you attack my "perspective", "because he isn't insulting you."

WTF is your problem? Why do you feel you have to attack and insult everyone? I'm just trying to do my job.

This one isn't going to last much longer than the others.

 

How to judge the quality of any Ported set of heads?

There a bunch of different things to look at.... what they flow CFM per square inch of valve size, Discharge coefficients, Velocity profile of the heads....etc

there is no point in looking at anything else to judge your heads. until you get the main problem with them fixed.There loosing flow/chokeing... you need to get the air speed in check, so it will stop backing up

If you dont, the heads will never make the power they could. and they will probably use more fuel in the process

One more thing, Port Volume doesnt mean 2 much. It is just the byproduct of getting everything else right

 

From what can see your exhaust flow looks good BUT, your intake side it looks like it needs more work.
This is my opinion, so take it for what its worth.
Look into it, because your intake low lift flow is great but once you get to .500 - .600
the flow falls off and drops this might be a concern especially with the lift cam you have and the kind of motor you are building (383).
Off the line this car will roast tires off the rim but at the mid-higher rpm range
your power will level off real quick.
The last set of heads I ported for myself for a 383 had very similar numbers like yours.
My car was real quick out of the hole but it felt it leveled off real quick at about 4000rpm.
It was fun as hell around town for part throttle response and highway cruising.
Not trying to flame only trying to help

 

OK, so I'd appreciate some help in interpreting the intake flow numbers. Might get some useful feedback on what can be done to bump up the higher lift flow.

Here's something to kick it off that SStokerAce posted earlier:

the .100-.200 numbers don't matter much....
The .300-.400" lift numbers...usually tell you how good of a valve job you have, but a port with a taller short side radius will have better numbers there but the port quality can go in the toilet which is much more important. The .500-.600" numbers and beyond (on street stuff) give you a indication of the ports ultimate shape, to pick these numbers up you need to know what you are doing in that area.

So it's already been made pretty clear that the port floor/ short side radius was minimally modified. The throat area was opened up to come more directly off the seat on this side so the short side radius was mainly just blended into the cut used to open up the seat diameter on the short side of the port. Maybe the port floor could use a little work? Some I've seen have a flatter floor with less height in the hump area of the floor. I kind of doubt that anything has been done to kill the upper end flow as mainly the height and to a smaller extent width of the port was modified, and not much at that. I wonder if the rest of the port has more potential but the air is separating from the port floor as the valve curtain opens up at higher lifts and this is causing turbulence?

Just a theory, open to others

Later, Michael

 

I really judge this in 2 catagories. I found home porting to be very easy and well worth the cost of aluminum oxide sanding rolls or carbides. I used cone shaped sanding rolls and smoothed out the castings in the intake runners as well as the bowls. The sanding rolls are very easy to use and don't remove very much material so you don't have to worry about giving each runner or bowl a different cc or flow rating. I used a carbide to gasket match the intake runners and then used the sanding roll to even it up. very effective and relatively free. Ive had experience with bowls before so that was a easy after a few heads of practicing.
BUT, here's where the seperation begins. Professional head porters study and find the best way to route the air. basically, they shape the ports and bowls to flow better, not just smoothing the castings. It's commonly known that the best shape to deliver air in a cylinder head is an oval. many porters will try and get to that shape, or create that shape by using fillers. I'm no expert on lt1 designs, but i'm assuming they try and shape the bowls and runners to best suit flow. Thats where it pays off to have a good ported head from a pro. In my situation, my own job turned out well. probably another 10rwhp or so i gained from the work i did. i figure that good for the cost of 40 bucks for a lot of sanding rolls and one carbide.

 

Mr. grammer, you mentioned you have a few porting books on hand, I would definately study a bit more to find out what happend. I ran into the same problem when I did mine a few years back. I wish I could have an answer for you, but I got stumped and almost ruined my heads.
If you have any professional porters in your area, I would talk to them and get some advice. You might get the info you need.
Good luck I hope it works out.
BTW i just posted my numbers up for my heads you mentioned you were interested.

 

Oh NO, before I would EVER switch that welder on I'd make sure and sweep the floor for years first.

 

Lol thats too funny.
Like any trade/skill, practice, time, & a few mistakes gives us the experience we need to do the job right.
Alot of guys do start off as a floor sweepers before they get into that position/trade. The last machine shop I worked at, I was the poop boy for a while just to get my foot in the door and then it progressed to simple jobs and then to advanced plans. Basically taking plans and programming cnc's to make the parts. From nothing to something alot of places are like that.