Ported head

AzCoupe

AzCoupe

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Departed Member
I have a cylinder head being ported, so I stopped by today to see how it was going, and to take a couple pics. He was a little upset because I didn't call first and give him an opportunity to clean it up, but it didn't matter to me. ;)

He is pretty confident he'll get a gain of 10-15% in air flow. If so it will put the intake around 230-240cfm. The head is being ported for street/strip, so he's concentrating on lift ranges between .300-.500cfm, with peak power around 5500rpm. Notice the work on the chambers, in the bowls, and around the guides.


ports01.jpg


ports03.jpg


ports04.jpg


ports05.jpg
 
Are there any lumps/bumps that are removed before 'polishing', or is the 'porting' in this head simply blending the curves?
 
InlineUK":wmba3810 said:
Does grinding the valve guides to that extent reduce their strength or durability?
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Nope, there's plenty of material to support them, and most of the guide is up (down?) inside the head.

Compare those tapered guide bosses to a stock head (especially a Buick), and you'll wonder how stock engines even run.
 
Mike, the ported head looks great.

The ports may flow so much that on a 200 one could loose some midrange torque. A smaller camshaft on a 200 might help.

For a 250" they are right on. Great job, Bill
 
I'll post more pics and flow test results once the head is done, which will be around the mid Feb. We plan to flow test the front three intake ports, to see how much difference there is due to intake runner length, as well as a couple of the exhaust ports.

Two of the exhaust ports have bumps where the head studs/bolts pass through. We never tested the heads to see how much it affects the flow, but will do so after the porting is completed.

He wants to drill the holes out (larger), insert a piece of tubing, then go into the ports and grind out the bump. This would make all the ports exactly the same, without sacrificing strength. I'm not sure if I want to go that far on this head, so I'll make that decision once the flow test are done. However we will definitely do it when we port a head for Will and Kelly's Falcon.

PS: I deleted all the post that were off topic (mascot), as I want to keep this thread on track.
 
Drilling out the head bolt hole to install a tube, reminds me of the 427 tunnel port heads. 8)

Mike the porting looks great,
It looks like a real breather.

Kevin.
 
I just got a call from the porter, and will be heading over to see the head on the flow bench in about an hour. All he would tell me over the phone, is that he got the 10% he was shooting for, which means the intakes are flowing in excess of 230cfm. :shock:

I'll post pics and flow numbers when I get home. Can you tell I'm excited. ;)
 
AzCoupe":1l54k3v1 said:
I just got a call from the porter, and will be heading over to see the head on the flow bench in about an hour. All he would tell me over the phone, is that he got the 10% he was shooting for, which means the intakes are flowing in excess of 230cfm. :shock:

I'll post pics and flow numbers when I get home. Can you tell I'm excited. ;)
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I can't wait to see the numbers. You might want to link in the old graphs of the flow numbers for comparison. (The ones that had all those other heads shown, too. I'm sure you know what I mean. :) )
 
Here's the results on the #2 intake.

bench1.jpg

bench4.jpg

elmo.jpg

Velocity @.100 lift (see green line @.600)
water.jpg

Before (out of the box)
chartbefore.jpg

After (race port)
chartafter.jpg

Graph
graphafter.jpg


That's a gain of 16cfm @ .300, 18cfm @ .400, 20cfm at .500 and 36 at .600 lift.

If I drop this head on my 250 block with 10.5 C/R, a 292 solid cam, 1.65 rockers, and triple Webers, I just might reach my goal of 300+ HP (naturally aspirated).

According to my engine dyno program, this set up would put out 367hp @6250rpm, and 340 lbs @ 5000rpm.

We'll seee...... .

:party: :party: :party:
 
I assume if I order a ported/polished head it will take longer to arrive. Say I order a fully assembled/p/p head. How long you reckon it would take before you can ship it out?
 
AzCoupe":1bz0xtzx said:
According to my engine dyno program, this set up would put out 367hp @6250rpm, and 340 lbs @ 5000rpm. ...
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NM_Shocked.JPG


Holy Saint Vroom-Vroom of the Blessed Wheelies!

That's amazing. Truly amazing.

Let's hope it actually performs like that.

:D
 
Wow, that is sweet. Say thanks to Elmo, he rocks. I've not seen flow numbers like that before on an I6, VERY impressive Mike.

I think stock Boss 302's were sitting at 200 odd at 500 thou, and that's what you have out of the box.

I seem to remember 265 cfm on a heavily reworked 4V Cleveland 351 at 600 thou was a benchmark for every racer.
 
350kmileford":d2rbecr9 said:
I assume if I order a ported/polished head it will take longer to arrive. Say I order a fully assembled/p/p head. How long you reckon it would take before you can ship it out?
Click to expand...

His work is in high demand here, as he does a lot of work for various race teams through out the SW. Hence it takes about six to eight weeks to complete one. He's been working on mine for quite a bit longer, since it was the first one and required a bit of research first. Before he started, we had a raw casting sent over and sliced it up into one inch segments so he could see the wall thickness at the critical points. I'll try to get some pics next time I go over and post them on the website.

Eventually we plan to have the head digitized and mast ported on a CNC, so they will be a stock item. But that's a few months off, as we want to test this one first to make sure it meets our desired goals.
 
Here's a new graph I made last night. It compares the intake flow of a 289 hipo, 351W, 351C, GT40, a log head, OZ250-2V, stock aluminum, and ported aluminum head.

flowchartsIN.jpg
 
AzCoupe":327fy8pa said:
Here's a new graph I made last night. It compares the intake flow of a 289 hipo, 351W, 351C, GT40, a log head, OZ250-2V, stock aluminum, and ported aluminum head.
Click to expand...

Very impressive. I notice that the ported head flows significantly better than any of the other heads at higher openings, but that it is beaten at some of the lower openings by some of the better V8 heads. I'm just wondering how that sort of flow characteristic would effect the torque curve of an engine and whether it means that a head ported in that manner would be less useful for some applications than the non-ported version.

Or would the fact that it apparently equals or beats the non-ported head mean that it would be better for almost any application where the added cost wasn't an issue.

Would the ported head really only make sense on engines with "racing" profile cams? Or would it also be beneficial on engines running milder "street" cams or "street and strip" cams?
 
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