extream head

The head flows as cast no porting 625 at .625 lift depends on what bore and valve size, they flow 100 cfm more then any other DT head out. And yes it had valves in it when tested ,not the head in the pic but the test sections. This head and the others are machined but don't get valves until the bore is decided. Sorry it not 800 I just don't pay much attention to the stuff I see every day.
 
what's the intake valve diameter? :confused:

I'm guessing this is a billet block with a huge bore? what's the bore spacing on a 466?
 
Still callin bs. .625 lift is wimpy.

400 series bore spacing is about 5.3125. 4.875 bore is about all that you can make a head gasket reliable at.

A bad ass canted valve Sonny Leonard head flows 640 at 1.300 valve lift on a 5.080 bore with a 2.850 valve.

Think, compare, think some more.
 
9724VF350 said:
Still callin bs. .625 lift is wimpy.

400 series bore spacing is about 5.3125. 4.875 bore is about all that you can make a head gasket reliable at.

A bad ass canted valve Sonny Leonard head flows 640 at 1.300 valve lift on a 5.080 bore with a 2.850 valve.

Think, compare, think some more.
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exactly!!! I'm not seeing 600cfm anywhere in that picture! LOL
 
Forrest Nearing said:
that's stock bore diameter... I'm talking bore spacing, which gives an idea of max bore diameter

I'm not from Missouri, but you're gonna have to show me 625cfm at .600 lift to believe it! LMAO the biggest AFR BBC head flows like 460 @ .900"
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Read ya wrong my bad, I don't have a 466 in front of me to measure that so I'm out. LOL
 
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800cfm, no way, no how, unless two are welded together.
 
Funny that you guys know more about the heads capability then those who have designed, cast,and tested it.It is a water jacketed head by the way If it wasn't any good are local puller wouldn't be waiting in line.And yes all 5 are spoken for.
 
renopker said:
Funny that you guys know more about the heads capability then those who have designed, cast,and tested it.It is a water jacketed head by the way If it wasn't any good are local puller wouldn't be waiting in line.And yes all 5 are spoken for.
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Yeah that is funny, but that don't change the facts. It very well may be a danged good head, and better than the competition, but 600+ is simply not the case.

You really think this parallel valved plain jane port angled diesel head flows the same at a full tilt NHRA pro stock head at half the lift?
Again, think, compare, think some more.
 
This head isn't mine but I do have a close connection to it and I know what it is capable of. I built and cast 440 heads in 1988 billet, again as cast 344 cfm @.800 @
28" with 2.250 intake . The thinking has been done and the parts are made.
 
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This CFM BS gets more tiresome every year - maybe I'm just becoming a curmudgeon...

No doubt the DT head flows 800cfm @ Xpsi - but good luck converting flow numbers at 10", 28" or 60" of water to accurate, reliable CFM at high boost pressure (60psi = ~1660"H2O)... not to mention that the numbers convey zero indication of flow quality outside of FPS range conventions - developed from & for NA applications, of course. :rolleyes:

Accurate forced induction flowbench numbers require an air supply capable of delivering, say, 1Kcfm @ 100psi; some of the OEMs w/generous R&D budgets have invested in such pressurized test equipment, along with a few well-funded racing programs - but for most others there's little resort to anything outside of educated guesses, empirical results & outright conjecture (gotta love flowbench racing!bif).

Lastly, observed flowbench data can - and often is - rather meaningless in relation to on-track results... there's simply no comparison between static flow numbers generated through a cylinder head on test equipment to the dynamic environment of an operating piston ICE which lends itself to accurate real-world extrapolation.
Even with the latest CFD analysis & modeling techniques, we are years (likely more than less) away from this capability just in terms of the required raw computing power.

A good head porter hates to hear "so how much does it flow?" from a prospective customer... just like dyno bragging rights, high flowbench numbers won't get you down the track any faster.
I just ask whether they'd rather buy CFM or HP. :)
 
LMAO

I had the same first reaction....hasn't changed much.
 
XLR8R said:
This CFM BS gets more tiresome every year - maybe I'm just becoming a curmudgeon...

No doubt the DT head flows 800cfm @ Xpsi - but good luck converting flow numbers at 10", 28" or 60" of water to accurate, reliable CFM at high boost pressure (60psi = ~1660"H2O)... not to mention that the numbers convey zero indication of flow quality outside of FPS range conventions - developed from & for NA applications, of course. :rolleyes:

Accurate forced induction flowbench numbers require an air supply capable of delivering, say, 1Kcfm @ 100psi; some of the OEMs w/generous R&D budgets have invested in such pressurized test equipment, along with a few well-funded racing programs - but for most others there's little resort to anything outside of educated guesses, empirical results & outright conjecture (gotta love flowbench racing!bif).

Lastly, observed flowbench data can - and often is - rather meaningless in relation to on-track results... there's simply no comparison between static flow numbers generated through a cylinder head on test equipment to the dynamic environment of an operating piston ICE which lends itself to accurate real-world extrapolation.
Even with the latest CFD analysis & modeling techniques, we are years (likely more than less) away from this capability just in terms of the required raw computing power.

A good head porter hates to hear "so how much does it flow?" from a prospective customer... just like dyno bragging rights, high flowbench numbers won't get you down the track any faster.
I just ask whether they'd rather buy CFM or HP. :)
Click to expand...

So lets cut all the flow in half and make more power? don't see any body doing that. You saying that the head flowing high cfm is departmental to its ability to make HP ? not buying in that either.
 
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