[X72GPX]

No, did not come with flow numbers, but want to have them flowed.

[Skip Fix]

Mine came Monday. CNC at intake port entrance on walls back to head bolt and down floor. Will pull some valve springs off to teat and look at pockets today. After it warms up here a friend and i will flow on his bench.

And not full of CNC shavings like the Edelbrocks I got back from KRE!

[X72GPX]

What do you think they flow?

[HWYSTR455]

I'm interested in what the seats and seat areas look like.

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[PAUL K]

Makes no sense that a ported head comes without flow numbers.... Especially a CNC ported head.

[Baron Von Zeppelin]

Originally Posted by X72GPX

Received them yesterday, what do you think?

For $1500 pair , I'd say you have done EXTREMELY Well .

Looks like they were mostly just getting the runners straightened up and trued and uniform..
That's all that most of us would ever need,
Worth the extra $300 versus the basic raw cast units.

Should be at least an extra 10-20 cfm over the raw cast 280 cfm .
Even if you don't use those springs you are still WAY ahead over what 1500 will buy on the open market.

Even at 280 cfm they are overkill for my needs.
But I'd pay the extra 300 to have them trued up like that - IF I were in the game for 1200 raw versus 1500 cnc

[Skip Fix]

Intake port 2.350-2.380(nit straight across top and 1.185 wide. Compared to a FelPor1233 raised at the top. going to need a taller gasket and a Torker 2 or tomahawk will probably need welding at top.

Valves have back cut stems and a rough swirl polish, no back cuts on head. Intake valve stamped 1074, Exhaust 1075. intake has 5 shims under it IH 1.775, exhaust 4 shims 1.795 IH. No shims intake 1.935, Exhaust 1.915. Valve spring free length 2.430. 1.775 IH 139 .600 lift 320 CB .770.770. Long free length had to unscrew compressor to release it. red stripe kind of like the 99893(?) Dave at SD uses and about the same seat. Valve keepers cut for lash caps and decent looking retainers.

Very basic 2 angle valve job large outer cut and the seat cut . there is a cut underneath both that is probably just form the CNC machine as is is not concentric with the actual seat. Seat in throat pretty rough from CNC machine. In throat seats i looked at have good base.

[Skip Fix]

More

[Skip Fix]

seats

[Stan Weiss]

I don't know that much about these heads or what they say the CNC work will do. But the only time I have seen this on a CNCed head is when there is core shift.

Stan

[Steve C.]

Skip's comment regarding the intake port height will become important depending on the intake manifold of choice...

Intake port 2.350-2.380. Compared to a FelPor1233 raised at the top. Going to need a taller gasket and a Torker 2 or tomahawk will probably need welding at top.

A fwiw, without welding both a Holley Street Dominator intake and a Tomahawk intake will go about 2.300" tall on the port height with about 1/8-inch above for sealing.

Below is an example of welding a Torker II intake in order to raise the ports for use on a cylinder head with very tall ports:

https://www.motortrend.com/how-to/cc...a-dcb8eba7ac8a


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[Baron Von Zeppelin]

Some Core shift has been a common feature on these SM heads from what I have read so far.
And most all others too - as cast.

I'm thinking the CNC work is mostly about "anti-doting" that feature up to a better degree.
Anything else they pick up in the balance is gravy.
Should be a quieter port now and likely higher flow numbers

That's a lot of head for 1500 - I don't care which ho' house you go to !

[Baron Von Zeppelin]

If intake modding is going to be a full requirement , they reached too far on my scale.
That's race stuff territory.

Suppose the intake port on the head could be epoxied instead ?
Thats still unforseen work involved for just a hot street car build around 500 hp

[X72GPX]

Originally Posted by Baron Von Zeppelin

Some Core shift has been a common feature on these SM heads from what I have read so far.
And most all others too - as cast.

I'm thinking the CNC work is mostly about "anti-doting" that feature up to a better degree.
Anything else they pick up in the balance is gravy.
Should be a quieter port now and likely higher flow numbers

That's a lot of head for 1500 - I don't care which ho' house you go to !

That is funny! I’m just happy they are usable and not boat anchors.

[HWYSTR455]

Those seats look much better than a lot I've seen.

.

[Gach]

Intake port 2.350-2.380(nit straight across top and 1.185 wide. Compared to a FelPor1233 raised at the top. going to need a taller gasket and a Torker 2 or tomahawk will probably need welding at top.

Just for example my Wide Ports are 2.360 tall and ported Victor intake has about 1/8 to seal,
PS: I haven’t had any issues with it sealing Butler sells intake gaskets can’t remember dimensions, that work for taller port.

[Gach]

My only other concern would be once these heads are bolted on block, how much of a port miss match there would be. If you’ll be cutting the intake or the heads, to make them match up. May have to use a double thick intake gaskets, Butler also sells them. So what I’m saying all this is all well and good, but this is something you won’t know until you actually bolt them to a block and try to match intake up to the heads. Could to be very interesting

[Steve C.]

Butler suggested intake gasket for their wide port heads...

Pontiac Wide Port Intake Gaskets 2.48 X 1.48

https://butlerperformance.com/i-2445...pm-5420-2.html

Side note on intake manifolds for their wide port heads:

"Aftermarket intake manifold choice is presently limited to our custom sheetmetal or a Wide Port-modified Edelbrock Victor, BOP Engineering's cast-aluminum four-barrel, and Wenzler's Gutsram"



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[PAUL K]

Kinda interesting to know if their "copy" of the Tomahawk manifold they sell will work with their CNC ported heads.

[Baron Von Zeppelin]

CNC =
Intake port 2.350-2.380
and 1.185 wide.

Can anyone measure and post what the as-cast versions measure ?

In retrospect - who was it that guesstimated 320cfm zone on CNC ?
Was it Randy R. ?
Don't know who else would have been in position to give an estimation previously.

** Error on my part using 280cfm as-cast earlier , its 289 (290)

30 +/- extra cfm seems like more than just trueing up and flattening out the wobbles and ridges
… and it makes sense too , from a marketing point that will be based against a number (eventually).
This will be fun to follow.