Vintage Ford Intake Manifold CFM flow numbers

[shelbydoug]

I searched everywhere with no results at all.

Have any of you found a source publishing tested results of '60s Ford performance intake manifolds CFM flow numbers? I can't find anything.

Head flow numbers are by comparison easy to find.

Have any of you done Extrude Hone on any of the intakes?


I seem to remember Cobra Automotive offering Extrude Hone on the Cobra high rise intakes but haven't talked to them recently about it.

[roddster]

I was a subscriber to Hot Rod magazine from 1970 through to the end last year. I don't recall ever seeing data on intake flow in cfm.

[pbf777]

    Flow benching just an intake manifold alone 'might' product some interesting numbers, great for bench racing and magazine articles, but to produce something perhaps more relevant, the task is to bolt the intake to the cylinder head as flow tested and establishing the effect that the intake had on the previous cylinder head alone numbers. 

    Scott.

[shelbydoug]

Flow benching just an intake manifold alone 'might' product some interesting numbers, great for bench racing and magazine articles, but to produce something perhaps more relevant, the task is to bolt the intake to the cylinder head as flow tested and establishing the effect that the intake had on the previous cylinder head alone numbers. 

    Scott.

Yes but it would make sense to know if the intake manifold is going to be complimentary to the head or restrictive.

It seems to me that there is much flow bench testing on intakes and talk of intakes having good runners and bad runners and descriptions of as much work done to intakes as the heads in many instances.

To me it makes as much sense to match the intake to the head as matching the cam to the head.

If I have a head that flows 300 cfm at .600 lift, I'll bet that it isn't flowing 300cfm at .480.


To suggest that the intakes are looked at as irrelevant is a bit juvenile.

I'm only asking if anyone had a link to published testing results of Ford intakes, for my own purposes. That's all.   


I would think that a no response would simply mean that they didn't?

[pbf777]

............ it would make sense to know if the intake manifold is going to be complimentary to the head or restrictive.

To me it makes as much sense to match the intake to the head as matching the cam to the head.

    Since one is generally going to be choosing an intake from a finite sum and of that which is already in the market place, not to mention most of the intakes for most of these push-rod engines are pretty much of a know quantity at this point, though perhaps not in the minutia detail, but close enough that with reasonable familiarity as to to rule out idiotic match-ups, that anything more is becoming a study and this requires a certain sum of relativity and understood comparatives.   

It seems to me that there is much flow bench testing on intakes and talk of intakes having good runners and bad runners and descriptions of as much work done to intakes as the heads in many instances.

    Yes, but beyond my previous posted statement of fodder for magazine articles, and though one "generally" (in racing) is of the impression that there should be equality among the inlet passages, but then what about each cylinder head port passage, are they balanced, do the engineering requirements even permit for this?  But do note that in certain instances once bolted to the cylinder head, providing the air columns' real-life presentation to the head, effective lengthening and added complications of the overall passage, the actual effective impact here that solely of the inlet runners might provide a somewhat different even confusing impression.      

If I have a head that flows 300 cfm at .600 lift, I'll bet that it isn't flowing 300cfm at .480.

    If what your eluding to here is attempting to decipher the intake manifolds ability to harmonize at certain air flow quantities and velocities, etc., that's going to prove a bit more involved than just acquiring air flow numbers from a bench; and pretty much relegates the average person to my first paragraph of that most intakes available are known.      

To suggest that the intakes are looked at as irrelevant is a bit juvenile.

    I don't think anyone was implying that, but rather just attempting to aid others in a better understanding in the value of such observations.   

    Scott.

[shelbydoug]

You can make it as complex as you want to but it is a simple fact that air flow is proportional to horse power potential. Engines are air pumps.

For normal people, we attempt to explain the formula in simple terms. It's just easier that way.


In many Masters of Engineering degree programs, presentation of data is more then just 3 credits. It includes all sorts or artsy ways to present results including colorful graphs and simple charts that even MBA's can understand.


In the case of selecting components for an engine build, logic would dictate to match the components to be complimentary and to act as a simple integrated system. Data acquired isn't always absolute but a prime indication where one likely should search.

In the case of using vintage Ford intake manifolds, although their potential is likely known to more then just one engine builder and certainly many of the day, I need to translate that into language that I can understand and apply.

Someone probably has done that but so far I don't find that info readily available so it is most likely that no one wants to bother with listing the numbers or less likely, it is just proprietary.

As far as your statement about intake flows being already a known entity, nowhere can I find a mention or even suggestion of flow by current or recent manufacturers. So leaving that process up to investigating even if just for entertainment reasons to magazine builds seems more like being complicit in instigating conspiracy theory? In other words if you're proud of your product, show us the numbers. What's the BFD?


If magazine builds want to explain why the same engine with intake manifold A makes 25hp more at a certain RPM then manifold B, and they show something that likely is relevant like differences in flow numbers, good for them. That is solid engineering.

So far, no one has come forth willing to share that info so take your pick as to the reason. I don't really care why. I just continue to search for it. Call me compulsive if you like.

[csxsfm]

Ouch. On behalf of all the MBA's out there, it was engineers that designed the Tunnel Port. LOL

[shelbydoug]

Ouch. On behalf of all the MBA's out there, it was engineers that designed the Tunnel Port. LOL

Yes. It works well but here's the thing, you need to know how to apply it.

It is more then just picking something off of a list.

[pbf777]

I need to translate that into language that I can understand and apply.

If magazine builds want to explain why the same engine with intake manifold A makes 25hp more at a certain RPM then manifold B, and they show something that likely is relevant like differences in flow numbers, good for them. That is solid engineering.

     If a 'magazine' should choose to present any such statement (and they have often  ), as one whom has been a participant in magazine "tech" articles, I would advise one to establish a corroboratory source before running to the bank! 

     The final straw that resulted in our separation from participation in the tech articles with the "magazines" was when we were attempting to explain that the information we had supplied was not being presented accurately, nor in a fashion that provided for a proper conclusion (again!  ); and it was at that point that it was explained to me that they (magazine) didn't care if the "tech" was accurate or even true, "as we're not here to educate the public, we're here to sell magazines, and we believe that the manor in which we have chosen to wright the article would sell more magazines"! 

     But, I suppose this thread is evidence that 'I' was wrong; as apparently a great sum of the populace really didn't want the facts, rather something easy to read and entertaining!   

     Scott.

[shelbydoug]

I need to translate that into language that I can understand and apply.

If magazine builds want to explain why the same engine with intake manifold A makes 25hp more at a certain RPM then manifold B, and they show something that likely is relevant like differences in flow numbers, good for them. That is solid engineering.

     If a 'magazine' should choose to present any such statement (and they have often  ), as one whom has been a participant in magazine "tech" articles, I would advise one to establish a corroboratory source before running to the bank! 

     The final straw that resulted in our separation from participation in the tech articles with the "magazines" was when we were attempting to explain that the information we had supplied was not being presented accurately, nor in a fashion that provided for a proper conclusion (again!  ); and it was at that point that it was explained to me that they (magazine) didn't care if the "tech" was accurate or even true, "as we're not here to educate the public, we're here to sell magazines, and we believe that the manor in which we have chosen to wright the article would sell more magazines"! 

     But, I suppose this thread is evidence that 'I' was wrong; as apparently a great sum of the populace really didn't want the facts, rather something easy to read and entertaining!   

     Scott.

Too large a portion of the "population" (worldwide) believes what is in ANY print, what others post on social media and some even agree with entertainers like the Marshal Tucker Band, "I heard it in a love song, can't be wrong", unfortunately.


Being an unreliable source of information just makes one a joke like the "Inquirer" is but they do have their loyal followings. Some much so that it gets used primarily as a tongue in cheek source and limited primarily to being quoted in purely fictitious situations such as feature length movies like "Men in Black".

Depending on unreliable sources should not be part of the plan. So far I have found zero sources and zero information available. While I am a bit surprised, I am not pushed over the limit to suicide. On the contrary.

In actuality, I already have a plan previously acted upon and looking at what others have published would just be investigated as supportive or non-supportive of that.


Manufacturers are not magazines. Many are currently showing their own test results in aftermarket heads. Interesting that none, even folks like Ford Racing, haven't on the intake manifolds.

[roddster]

Ah,favorable press helps the magazine's bottom line.

[Road Reptile]

Hi,
Just thought back about a conversation with a local engine builder from years ago. He said the intake manifold was "Not as critical to port matching as time is better spent on the proper camshaft, and that it is the turbulence created inside that increases air flow and helps with power improvement." He also says that after spending hours port matching an intake it showed only 2 HP increase on the Dyno....Some science and math do apply and think of what has been learned in the aerodynamic field in the last 60 years.
If you get a chance look at a current Top Fuel engine and try to imagine power in that magnitude 10 years ago. What are you trying to get from a 1960's design???
R.R.

[camp upshur]

This information is available, open source.
This is not the forum for technical questions requiring specificity under controlled methodology.
I suggest Speed Talk or the FE Power forum (other engines) where posters such as Joe-71 (JOE-JDC) (now retired), and others such as Bill Carlquist and John Mummert have quantified the panoply of SBF single quad intakes, including baseline flows. Their interests are primarily rule-limited vintage racing and rule-limited competitions, such as Engine Masters.
Rememeber, the air begins prior to the intake and ends in the atmosphere aft of the tailpipe.
Good luck.

[gt350shelb]

You can peel this hobby like an onion ..  being interested in a facet  that  may or may change "your idea" of the onion  is part of the interest that keeps the hobby going forward .  how many times can you argue what color the floor is on a 67  gt 350.
 new thoughts are welcome and needed .

if i had the flow bench  doug and i would be doing some testing  .... even if we were the only ones that cared .

[JohnSlack]

I'm fairly certain from my conversations with Larry Ofria when I worked for him that Valley Head Service flowed the cylinder head intake manifold combination for the C6OE-A dual quad manifolds. Not necessarily for the numbers as to how well they were flowing but to make sure that they actually got the flow improvement that Shelby was paying for.

Later on in my conversations with Dan Case regarding the C6OA-E T/A intake he seemed to think that Mondello's head intake combination for the T/A intake was flowing better than the VHS combination.

The intakes were available in limited numbers to the Shelby people, definitely not available for Bud Moore's LM Cougar cars. The intakes provided to Shelby privateers were not modified by either VHS, Mondello, Charlie Slover or Ken Sperling. But out of the box.

I think that some of the numbers you are looking for are based on conjecture as the flow benches were not consistent with each other. Larry's VHS flow bench took up a whole room and was a magnificent piece of equipment. I never saw Mondello's or Ken Sperling's flow benches I saw Charlie Slover's bench but I doubt that the machines were as consistent as a modern flow bench mass produced. Even the modern flow benches have to be calibrated to get consistent numbers. For in house usage back in the day you could see on a port to port basis if the work you accomplished was a good result or not. However if you wanted to compare the intake manifold from this group to that group you would have had to choose one bench to use.


So even if you found the information you desire it would be junk compared to what you you could achieve today.


John