What do your heads flow?

Posted By: bwhackd34

Re: What do your heads flow? - 07/16/12 01:28 AM

Not a typo...I have been working on developing this design for close to 2 years....8/24/10 was the initial flow test. Have made a few more advances since that post.....velocities have improved as has flow...I continue to reiterate that this is a test how....how it will translate to a working port is yet to be determined but the numbers are valid.....have actually recently gotten very close to 470+ albeit it at 1.00" of lift.....at .875" lift the best number to date....and the current...is right around 455. Just to be clear the project is much more than a port job....my intention was to push the limit on the factory parameters of the w9...the port is within the factory external dimensions....no welding, moving of guides or anything of that nature....this model has seen 100's and 100's of hours od grinding, testing, probing and reshaping. What didn't work was redone...epoxied or clayed over and redesigned...what I have now is the result of all that....once I am satisfied with the results I will convert to a fresh port, retest and hopefully find someone to digitize and CNC as I don't think I wish to copy the design to a new set if heads by hand...

Posted By: dizuster

Re: What do your heads flow? - 07/16/12 02:17 AM

How big of a valve, what bore size? Is this a W9RP?

Impressive either way. Good of you to point out these are flow numbers only, not dyno or track times. Hopefully though the big numbers you are getting translate into good results in the car.

Posted By: bwhackd34

Re: What do your heads flow? - 07/16/12 09:50 AM

No...not RP's....847 castings.....valve is larger than most, 55 degree seat, 95-96% throat....I have no intention of misleading....makes no sense...if I was to purposely inflate or just plain make up numbers the low lift would be better....it is what it is however....but I think the high end makes up for it...heads are designed for a 4.185 bore....actually don't like much larger and will drop in flow if unshrouded too much more....thanks

Posted By: moderncylinder

Re: What do your heads flow? - 07/16/12 08:16 PM

i still think you need to validate your numbers on another bench and have them post what they are here,,, nobody gets those heads to flow like that up high cause they just arent big enough,, your numbers up to .700 lift are normal or down,,, those heads flatten out past .600 and flatline at .800 usually at 420 or so if real good,,, you getting 470 is crazy good,, and you would need to be big enough to move that much air through,, 95.5 % throat which is huge again,, leaves you like a .020 wide bottom angle,, which usually doesnt work,, but you mention velocities through the throat and then the port,, implying your minimum cross section is 3.00 sq inches of area,, if you have a 2.300 valve in it,, which i dont think will fit in that head,, but you wont say like its super secret,, so ill guess its some huge valve, which is big,, but normal for min area..

i though you said this is going on a street/strip pump gas motor,, if so why focus on airflow from .800 and up?

Posted By: bwhackd34

Re: What do your heads flow? - 07/16/12 08:26 PM

Again....my bench is calibrated and has been verified against another local bench when the heads were flowing below 400....most of the low lift numbers are very close to what they were then....I do, however, fully intend in having the finished product re-verified. I never mentioned pump gas street/strip and agree that would be assinine. I don't do this to get in pissing contests....I do it because it is what I enjoy and I do it solely for me....I have merely shared my results here as many before me have done...if everyone is only to get the same results as all before them why even bother trying....

Posted By: bwhackd34

Re: What do your heads flow? - 07/16/12 09:07 PM

I will also say that this particular design is not something that someone will ever accidentally stumble across....it has taken nearly a year of testing and modifying daily to achieve what I have thus far.....part of the reason I choose to keep some aspects to myseld thus far is that even though the flow is great and the velocities are really good does not mean that the particular design will also be conducive to big HP....I hope they will but anyone who does this for hobby.or living will be quick to tell you that in this game sometimes numbers DO lie....

Posted By: bwhackd34

Re: What do your heads flow? - 07/16/12 09:21 PM

Let me also reiterate that while my bench is calibrated to flow 592cfm in range 6 that is to do so at 25"....if I were deliberately trying to mislead I would base my calculations off of that info....AT THE VERY LEAST...and not bother with the .997 correction factor for flow capacity when flowing at 28".....while not a lot it would gain me some 'flow' but if the numbers aren't genuine I really don't see the point....in the past I had even posted some results that seemed positive BEFORE I verified as I was a bit happy to have them....only to realize why, at that time the gain occurred, and once that issue was corrected and the results proven not actual I deleted that post....I have since ACTUALLY gotten to that point and maybe even a but more but at that time the post was not accurate and was therefore immediately removed....

Posted By: moderncylinder

Re: What do your heads flow? - 07/16/12 09:43 PM

i am working on some ford d-3 heads for a drag race aplication which will have whatever lift it needs,, probably 1.000 or around there,, 2.250 valve and i need 470 or so cfm,, like what you have,, though my head has a canted intake valve so my mid numbers will be much more than yours,, my peak i hope to get what you have,, im looking to put it on a 373 inch motor that runs to 10,000 and make 1040 hp,, i need a min cross section of 3.75 to do this,, you cannot get that big due to the casting restraints you have,,

if you have airflow,, port cross section to support displacment,, and mixture motion entering the cylinder that all works,, it WILL make power between 2.2-2.4 hp per cfm,, so if you put your motor together and its serious, id expect 1040-1100 hp,, if not,, the head isnt what its supposed to be,, its that easy

that being said,, my 373 inch motor in a 2825lb car,, should go 7.70's with a liberty 5 spd,, making 1040hp at 9600-9800rpm

Posted By: Moparnut426

Re: What do your heads flow? - 07/16/12 09:53 PM

Mine sometimes flow air with burned fuel and hydrocarbons, and sometimes flow air, just depends on which cycle the engine is on at the time..

LOL

Mine flow 295ish intake and 165ish exhaust so I was told.

Small block indybrock that is basically just cleaned up a tad, and opened up a touch. Runs damn good though!!

Posted By: bwhackd34

Re: What do your heads flow? - 07/16/12 10:27 PM

Like I have said before.....if theory was law everyone's heads would be perfect and flow exactly the same.....if theory was law porting and cylinder head design would be easy and we would already know all there is to know...

Posted By: bwhackd34

Re: What do your heads flow? - 07/16/12 10:36 PM

thermo and fluid dynamics are a science....as such...they are not exact, there are exceptions to every rule and what we know today could very well be proven wrong tomorrow.....MCA is just that....the minimum cross sectional area....no one ever said it had to be in any particular place...it could be at the intake flange, the SSR, the throat or the seat....it is merely the part of the port that has the smallest measured cross section...

Posted By: rickraw

Re: What do your heads flow? - 07/16/12 10:40 PM

with those flow #'s, how much metal is left in the ports? i would think, really thin.

Posted By: bwhackd34

Re: What do your heads flow? - 07/16/12 10:48 PM

Some areas are no doubt thin....I have found.....wink wink....a lot of the areas that simply cannot get any larger.....this is one of the reason why I have so much time in R&D and also specify that I am not sure how it will translate to a 'real' port....

Posted By: bwhackd34

Re: What do your heads flow? - 07/16/12 10:55 PM

I would guess that you subscribe to the intake port mach effect as you have a target MCA.....just as this theory has many propponents it has many opponents....there are those that say this theory only applies to the exhaust port and the intake does not become limited....like I said....if theory was law this would be easy....I do however quite enjoy our debate....there are no hard feelings on my part and you mentioned that Ford before....sounds awesome!....hope it works out!

Posted By: bwhackd34

Re: What do your heads flow? - 07/16/12 11:13 PM

Actually however, there are areas of the port that responded better and gave me greater results.....much greater....when material was added.....not just for the sake of adding but to reshape the port and 'direct'(as much as it is not the proper term) the flow....the port is not concentric, it is not geometric and it certainly isn't pretty....but to paraphrase what a wise porter once said "if we could attach a piece of string inside the port and make it stay we would, if that would flow better"....

Posted By: moderncylinder

Re: What do your heads flow? - 07/17/12 01:19 AM

it is no theory that minimum int cross section limits cylinder filling in the comp stroke, thus limiting the peak engine speed of the engine,, you cannot "cam" the motor to run past where the int port will peak,, though many think you can and try to do it causing you to loose power everywhere,,

i have a dyno here,, and see it,, as with talking with my friends/customers who race nhra,,, super stock,, comp,,, or pro stock

Posted By: pittsburghracer

Re: What do your heads flow? - 07/17/12 03:35 AM

Jeff if he is ever willing to verify these flow numbers on another bench I am willing to offer my bench. I will throw a test plate on to verify my bench and we will then use his bore adapter and do the test. I will do this FREE of charge as long as he agrees that I post ALL findings. All flow number will be posted along will bore adapter size. I am located 35 miles NE of Pittsburgh, Pa. if he is interested.

Posted By: DakFink

Re: What do your heads flow? - 07/17/12 07:10 AM

Quote:

i am working on some ford d-3 heads for a drag race aplication which will have whatever lift it needs,, probably 1.000 or around there,, 2.250 valve and i need 470 or so cfm,, like what you have,, though my head has a canted intake valve so my mid numbers will be much more than yours,, my peak i hope to get what you have,, im looking to put it on a 373 inch motor that runs to 10,000 and make 1040 hp,, i need a min cross section of 3.75 to do this,, you cannot get that big due to the casting restraints you have,,

if you have airflow,, port cross section to support displacment,, and mixture motion entering the cylinder that all works,, it WILL make power between 2.2-2.4 hp per cfm,, so if you put your motor together and its serious, id expect 1040-1100 hp,, if not,, the head isnt what its supposed to be,, its that easy

that being said,, my 373 inch motor in a 2825lb car,, should go 7.70's with a liberty 5 spd,, making 1040hp at 9600-9800rpm

W9's were what the NHRA ProStock trucks used to run 7.50's with 358cui in truck that weighed the same IIRC. So they should be just as capable.

For all the nay-sayers has anyone gotten a hold of or talked to anyone that had first hand knowledge of the ones used in ProStock Trucks??

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 10:18 AM

I appreciate your offer....as stated previously....once I have a finished product with which I am happy I have someone about 15 miles away with a Flocom SF600 that will verify my results....our benches flow very similarly....as calibrated Superflows should...so I am not concerned with differing results....the one thing I find peculiar is that Jeff tells me my low lift numbers are down but my high lift cannot be that high......seems as though my bench has some odd ability to both increase and decrease numbers at different lifts in the same test according to what others believe they should be.....I would think either numbers would all be up or all be down across the board......

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 10:42 AM

Assuming this 'theory' has validity....I believe it was Darin Morgan who said it is not correct....you are assuming that the air column is 'seeing' the port in the same dimension as you....we look at the cross section physically...we take measurements and calculate a uni-dimensional volume for that very specific point in the port....that is dine assuming that the air is moving.perpendicular to that point...however air very rarely flows with such 'proper' direction...if the line of flow is skewed any amount from perpendicular then it will 'see' the window at an angular view effectively making the area larger....again....science is not exact or cut and dry.....this may be the reason that Darin said this theory lacks a level of validity because we are wrongly interpreting the data....

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 01:55 PM

Quoted from a thread relating to CD...

) Can it be too high causing something to sonic choke at the SSR? Yes it can choke but NO it cant Sonic choke. There is no such thing as Sonic choking in an intake tract. They operate at a maximum of about.5 to .55 mach 600+ft/sec, which is far below Mach. If the mean velocity in the intake tract where to exceed mach .55 the power would drop off dramatically. Sonic only occurs on the exhaust side and usually at lower lifts in super charged engines.

Darin Morgan

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 02:03 PM

Not saying he is right or wrong....although he is head of cylinder head development.at Reher Morrison....just illustrating my point that the theory has its.opponents as well....

Posted By: moderncylinder

Re: What do your heads flow? - 07/17/12 02:16 PM

darin is correct for the most part,, but what he said and what i said arent the same,, read it again,, i never said the intake ports go sonic,, exh ports can,, beacuse of the pressures in the cylinder when the exh valve is initially opened.. the intake port cross section will just limit how high the engine will peak at,, everybody knows that....... and pro stock trucks used w-9 heads when they were slow,, they used p-5 heads when they were fast,, also,, a "good" pro stock truck w-9 flowed just about 390-400,, which is enough to make 950hp,, he is claiming 470,,, see my point yet???

also,, i have a cnc machine,, and computer software for it,, i can see the ports on my computer screen and slice them wherever i want,, not use calipers and guess,,, plus like i said,, ive worked on engines along with others,, and witnessed peak power at a predicted rpm based on minimum int cross section and runner length

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 02:34 PM

I don't know where to go from here....I am not 'claiming'....it is what I have achieved on a calibrated and verified bench....I don't claim it will work or make power....I am simply posting my results.....I expected there would be some naysayers....Jim I respect you for what you have done and all your achievements...it is too bad that instead of being reciprocal you need to try to convince everyone that these results cannot be as you have never gotten them.....I remember the days when a 350cfm port was considered astronomical....I am just glad that at that time there were people who felt there was still room for improvement and not that since that is all the porters of the time were getting that that must be all that is possible....

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 02:50 PM

It is the same....the whole reasoning behind this theory relates to the MCA controlling the velocity....that at a specific cross section and RPM the air will be travelling at a given velocity based in what the port flows....that this velocity...if it reaches a certain speed will sonic choke the port thus making power drop off after this point....the intact tract length controlling RPM is a different theory and relates to the range at which.sonic pulses will aid in cylinder filling based on the timing of the pulses to be synchronized with the intake valve opening.....

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 02:58 PM

If not for its ability to influence velocity...then what other reason would there be for the MCA to control where an engine will make power?

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 03:29 PM

What I have found....and this is just me....is that the as cast bias of the intake.port is not conducive to very high flow numbers....perhaps the PS heads were ported on the factory bias and thus the reason they were limited to around 400....I in no way claim to be a better cylinder head buy than anyone, let alone the PS guys, I just try different things to see what works rather than rely on conforming my design to what everyone else says works.....

Posted By: moderncylinder

Re: What do your heads flow? - 07/17/12 06:32 PM

the mca,,,,, will effect the ports pressure on the cylinder during filling in the compression stroke,,, when you have a port that flows extremely well,, its obvious the filling in the intake stroke will be enhanced,, therefore when the piston starts comming up, compressing that mixture there will be more charge in the cylinder, causing more pressure,, the point at which the pressure of that compressed mixture becomes equal to that of the inertia pressure in the intake runner becomes equal,, you must close the valve,, inertia increases as engine speeds comes up, or gets higher to the point that the mca restricts it, causing it to stall, and not produce anymore,, therefore anything past that speed will push charge back into the runner if the valve is open longer, loosing power

its not that "I" cant get your numbers,, nobody on the planet,, but you,,, can,,,im not saying they arent true,, id just like to see you validate them with somebody else,, its not like you got 440 out of them,, which would be a high number,, but maybe possible,, you got 470,, that number is so high,, higher than anybody has heard, got,, etc...

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 06:49 PM

According to this explanations a high flowing port with a smaller MCA will make more power than a like.flowing port having a larger MCA as the smaller port will have more velocity and consequently higher inertia allowing more charge to RAM the cylinder, the valve.to stay open longer and the piston to be higher in the bore before the pressure in the cylinder equals or exceeds the inertia ram...

Posted By: moderncylinder

Re: What do your heads flow? - 07/17/12 06:52 PM

no,, you missed it

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 06:54 PM

Quite the converse of what you were attempting to illustrate....by this definition it could be argued that the best power would be made with the SMALLEST MCA possible while still providing adequate airflow to fulfil the demand if the engine at the RPM you are trying to make power.....as too large an MCA will kill velocity and inertia and require the valve to close sooner before to avoid reversion.

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 06:57 PM

And if in fact no one else on the planet can get these numbers then I have accomplished exactly what I set out to do two years ago...

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 08:06 PM

Not sure what I missed.....Bernoullies law states that faster moving air.will have less pressure but that.is.in reference to.the pressure BEHIND the air column not in front....as speed(velocity) of an object(air) increases so does its inertia.....as MCA decreases velocity increases...pressure drops behind(vacuum signal at venturi) but inertia of the column as a unit increases and probably at something.like with.the square...

Posted By: MR_P_BODY

Re: What do your heads flow? - 07/17/12 08:31 PM

Not to get into this due to you guys are smarter than
me when it comes to heads but are you figuring in
the overlap of the cam which is drawing air/fuel
through the cyl to help keep the velocity up

Posted By: moderncylinder

Re: What do your heads flow? - 07/17/12 08:49 PM

overlap helps to draw in charge when inertia is almost non-existent,, at higher speeds overlap is needed less and less

im glad to see you have it figured out,, so a smaller cross section will not limit the engines ability to "fill" and actually enhance it as engine speed increases? too bad it doesnt actually work that way,, in real life....

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 09:08 PM

Two cylinder heads, all else equal, the smaller MCA(and we are talking within reason...not to any extremes like a 2")should, according to the definition you stated earlier, make more power...

Posted By: mafo

Re: What do your heads flow? - 07/17/12 09:12 PM

I don t think they ever used w9 s on pro stock trucks, w8 and p5 s

I have some early nickens w8 s , they flowed 410- 412 on my bench , my CFE s flowed 402 -403 on the same bench

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 09:16 PM

I will continue my stance that most of what we are talking is theory and not law...the Bernoullie effect however IS law....and as such is open to much interpretation....if it was set in stone we could take CA 'A', CA 'B' and CA 'C'.....connect them...take them over the SSR at about 10* blend them into throat diameter 'X' through valve diameter 'Y' and over seat angle 'Z' and have the perfect port everytime.....unfortunately the real world does not work THAT way and as such we have flowbenches, dynos and computers to anaylize all our data and tell us what actually works....

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 09:28 PM

I was picking my battles.....wasn't gonna argue that point...

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 09:30 PM

Also don't consider the rest of the thread, and hope Jim doesn't either, arguing but rather debating......

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 09:36 PM

For the sake of arguement.....if I was to post that I made some changes today and now my port flows 400 would you say that my bench is not correct....because I have been there and can do that....I can 'undo' some of my work and make it flow 380-400....then I can reapply what I have learned...although it takes time to 'get it right' and get back to where I am....I have done it many times along the way....when it seemed I hit a wall I went back to point 'A' and tried again....

Posted By: Triple Threat

Re: What do your heads flow? - 07/17/12 09:39 PM

My heads flow 280@.600

Small block eddies, 2.02 valve

Posted By: moderncylinder

Re: What do your heads flow? - 07/17/12 09:56 PM

Quote:

Two cylinder heads, all else equal, the smaller MCA(and we are talking within reason...not to any extremes like a 2")should, according to the definition you stated earlier, make more power...

this is based on your conclusion on how velocity operates in a port,, maybe based on you thinking its like a flow bench and the port is "on",, not in a running engine that has "velocity" of the charge as dictated by the piston speed/depression created in the intake stroke,, there is no vaccum in the compression stroke to generate velocity,, it is created by the residual charge in the port upon sweeping the intake stroke,, which we call inertia,, which impacts the cylinder as the piston is comming up,, the smaller the window it has to flow through,, the less of an impact it has AT HIGHER SPEEDS

a side note,, in drag racing,, "we" try to make power at higher speeds,, to get down a 1/4 mile track faster and quicker

Posted By: joshking440

Re: What do your heads flow? - 07/17/12 10:03 PM

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 10:21 PM

No...thank you....that is the point I have been trying to illustrate all along.......that is based on your comment that my heads need to have MCA dimension 'A' or they cannot flow what they do.....I am trying to illustrate these theories are guidelines not rules....YOU said they are not theories they are proven...now you are saying that I am the one claiming these are concrete because of how I believe air flows on a flowbench.....I am simply saying that just because YOU need a 3.74MCA does not mean I do...you said they cannot flow 470 unless they have that dimension.....

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 10:28 PM

HAHA....that about sums it up perfectly!...

Posted By: moderncylinder

Re: What do your heads flow? - 07/17/12 10:43 PM

with a w-9 head it is impossible to get 470cfm through a 2.8-3.0 minimum cross section,, it just isnt big enough,, period,, im tired of this stupidity,, nobody on the planet in comp, pro stock, nascar, or whatever has even came close to that number,, but i guess you figured it out

show me the timeslip? that sums it up? mr bwacked,, what have you worked on that has made 2.2 or more hp/cubic inch? for real

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 10:46 PM

First of all...Jeff....I apologize I kept referring to you as Jim....second....let's just agree to disagree...we are all here because we have some common interests and should not be turning this into a battleground as I am sure that is not what the developers had intended.....as I said before I respect you for your accomplishments...if you cannot do the same for me I respect that....but I herein have decided to discontinue this debate before things get ugly....good luck on that Ford!

Gary

Posted By: fishy340

Re: What do your heads flow? - 07/17/12 10:56 PM

i think the best way in the world to see these badboys,is to build a 440ci sb motor with them heads on it,,,if they work you should be able to make over 1000 hp with the w9's ur workin on...i know its been done with Sb2's by a local builder here on long island,and they flowed around 420ish int and close to 300exh

Posted By: bwhackd34

Re: What do your heads flow? - 07/17/12 11:10 PM

I have never claimed anything more than what they flow.....I continue to say that they could prove to make no power at all...I also never specified a 2.8-3MCA....just to set the record straight....thanks for your input....I am working on these for a 468 2x4 on e-85.....time will tell!

Posted By: fishy340

Re: What do your heads flow? - 07/18/12 12:40 AM

http://www.youtube.com/watch?v=J1Mu7f0qMTs&feature=player_detailpage

Posted By: rickraw

Re: What do your heads flow? - 07/18/12 01:57 AM

dang

Posted By: Ian

Re: What do your heads flow? - 07/18/12 02:01 AM

there is some great info here well worth a look
http://www.performancegarage.com.au/blog/cnc-myth-busting

Posted By: fast68plymouth

Re: What do your heads flow? - 07/18/12 02:41 AM

Quote:

Let me also reiterate that while my bench is calibrated to flow 592cfm in range 6 that is to do so at 25"....if I were deliberately trying to mislead I would base my calculations off of that info....AT THE VERY LEAST...and not bother with the .997 correction factor for flow capacity when flowing at 28".....while not a lot it would gain me some 'flow' but if the numbers aren't genuine I really don't see the point....in the past I had even posted some results that seemed positive BEFORE I verified as I was a bit happy to have them....only to realize why, at that time the gain occurred, and once that issue was corrected and the results proven not actual I deleted that post....I have since ACTUALLY gotten to that point and maybe even a but more but at that time the post was not accurate and was therefore immediately removed....

i'm not going to get into a debate on what your heads could or couldnt flow.
if i had one on my bench....whatever that number was would be what they flowed as far as i was concerned.

i do have one question though about your .997 correction factor and how you're applying it.

are you flowing at 25" and correcting to 28", or are you flowing at 28"?

the reason i ask is, the correction factor from 25" to 28" isnt .997(which i'm sure you know), so i'm just wondering where it fits into the equation.

Posted By: Anonymous

Re: What do your heads flow? - 07/18/12 02:48 AM

My Stage V big valve heads fully CNC ported flow +500.
Don't have the exact # because I don't have the charts yet.

Posted By: tubtar

Re: What do your heads flow? - 07/18/12 03:10 AM

Int. @ .100 .200 .300 .400 .500 .600 .700
c.f.m. 76 157 234 295 334 349 348

Exh.
c.f.m. 59 124 186 225 243 250 253

W-9's ported with a conservative approach and an eye towards mid lift flow #'s. I think they'll work O.K.
The whole motor is a series of compromises since it was built with stuff that was available and affordable over a couple - three year window.
It should have a bigger bore ( it's 4.125 " ), but that could change in the future. It could sure stand more cam ( 260 / 250 @ .050 and .668 lift ) , and it might like a bigger carb too.
But the time slip will be the final arbiter here.
This is the first time I have had a set of heads done up for me , but this is also the most motor I have ever attempted to screw together too......I didn't trust myself to home port them and had too much $$ on the table to risk messing them up.
I think I'll be happy with the end result.
If not , there is always a plan "B".

Posted By: LaRoy Engines

Re: What do your heads flow? - 07/18/12 04:29 AM

Quote:

And if in fact no one else on the planet can get these numbers then I have accomplished exactly what I set out to do two years ago...

Yep, I understand.

Posted By: MR_P_BODY

Re: What do your heads flow? - 07/18/12 04:58 AM

W-9.. CNC ported then touched up... 365 at .700...
small lift and to big of duration cam and small bores
but it is what it is... it doesnt break anything

Posted By: Al_Alguire

Re: What do your heads flow? - 07/18/12 05:29 AM

Well FWIW my B1MC's top out at 452-457cfm, on three different benches over the years. The 99's are at 590 at 1.000". The -1's for the street car are at 370. All of these are hand ported heads no CNC stuff. B1's by Mike Duke,99's by Schumacher racing then Mike Duke.

Posted By: Thumperdart

Re: What do your heads flow? - 07/18/12 05:48 AM

Quote:

Well FWIW my B1MC's top out at 452-457cfm, on three different benches over the years. The 99's are at 590 at 1.000". The -1's for the street car are at 370. All of these are hand ported heads no CNC stuff. B1's by Mike Duke,99's by Schumacher racing then Mike Duke.

All I can say is, DAMN..............I NEED to drive your car.......

Posted By: moderncylinder

Re: What do your heads flow? - 07/18/12 11:12 PM

Quote:

This has been a subject of other posts on here but I am working on a w9 port design that right now flows upwards of 445@.850" and very near 470@1.00. Velocity down the port is near 325-335 and about 260ish through the throat....port volume around 300cc....still a work in process...

when you stated this,,,,, and then saying 95-96% throat respective to valve size,,, though you never said what your valve size cause its top secret,, but assuming 2.250-2.300,, implys an mca of 2.8-3.0

really its just simple math,, unless what you have stated is incorrect

Posted By: bwhackd34

Re: What do your heads flow? - 07/19/12 12:44 AM

Quote:

Quote:

This has been a subject of other posts on here but I am working on a w9 port design that right now flows upwards of [Email]445@.850"[/Email] and very near [Email]470@1.00.[/Email] Velocity down the port is near 325-335 and about 260ish through the throat....port volume around 300cc....still a work in process...

when you stated this,,,,, and then saying 95-96% throat respective to valve size,,, though you never said what your valve size cause its top secret,, but assuming 2.250-2.300,, implys an mca of 2.8-3.0

Not following your math....if you are figuring the throat as the MCA then assuming a 2.25 valve its area would be 3.974...with a 95% throat the gross area would be 3.775 less valve stem area of .0923(assuming an 11/32 valve) for a net area at the throat of 3.683....if you are figuring the MCA to be elsewhere down the port it could be any size irrespective of these dimensions.....working backward.....with a flow of 450 and an MCA of 3.00 calculated velocity would be 357fps....

Posted By: Maximus_Wedges

Re: What do your heads flow? - 07/19/12 12:48 AM

This peein match is very informative.

Posted By: bwhackd34

Re: What do your heads flow? - 07/19/12 12:50 AM

By my math.....it has an AVERAGE CA of around 3.56....

V(in fpm)/cfm/12......should get you close....

Posted By: moderncylinder

Re: What do your heads flow? - 07/19/12 01:12 AM

260/330=.787878

.787878 x 3.683 = 2.90

now thats in general,,, but if you have velocities at those two points,,, and have area at one of those points,, you can "guess" at what the area is at the other

Posted By: DavidDean

Re: What do your heads flow? - 07/19/12 01:40 AM

This is turning into an informative post if you get through the B.S. Quite a few people who know thier stuff are posting. I wont post any of my stuff, its decent I guess but not tops.As some else has said we dont race flow benches or dynos. The numbers dont lie on the time slip.

Attached picture 7298411-DRCJamesDean.jpg

Posted By: bwhackd34

Re: What do your heads flow? - 07/19/12 01:48 AM

Your math is kind of right but you are going the wrong way.....as the CA decreases in size the velocity will increase.....ie. too large of a port equals low airspeed...so while the two airspeeds can be expressed as a percentage of one another the calculations need to be reversed to figure CA
V is cfm/A(sq ft)/60

So with a 3.687 CA
V is 450cfm/(3.687/144)/60
V is 450cfm/.026/60
V is 288 fps

With a 2.90 CA
V is 450cfm/(2.9/144)/60
V is 450cfm/.0201/60
V is 373

Given these speeds....2.90 is roughly 78% of 3.687 and 288 is roughly 78% of 373

Posted By: moderncylinder

Re: What do your heads flow? - 07/19/12 01:54 AM

so you are figuring out what your velocity is based on math and your airflow,, not the actual measured velocity in the port....

i usually try to stick to actual numbers that i can see and measure

sorry for any confusion,, back to your regular scheduled program....

Posted By: bwhackd34

Re: What do your heads flow? - 07/19/12 02:04 AM

With this formula and some creative math you can take the velocity and figure CA....

CA is V(ft per min)/cfm. /12

CA is 320(60) /450
12
CA is 19200/450
12

CA is 42.666/12

CA is 3.56 given 450cfm and 320fps

Posted By: moderncylinder

Re: What do your heads flow? - 07/19/12 02:07 AM

so now youre saying you have pretty much the same cross section at two places in the port, but the airspeed differs 60-70 fps at those two places?????

Posted By: bwhackd34

Re: What do your heads flow? - 07/19/12 02:14 AM

No...that is just how numbers fell out using 450 cfm and a 2.25 valve and the 78% ratio you got from the airspeeds......

Posted By: moderncylinder

Re: What do your heads flow? - 07/19/12 02:24 AM

ok you gave "us"

470cfm
260fps at throat
330fps at short side
95-96% throat of valve size

you dont see that by figuring back from the velocity at the throat, and the airspeed,, that some relation can be made to the area at the short side? it can...

must be all voodoo top secret spy porting suff going on here,, magic..

your ca formula doesnt work to real world data,, it gives a ca that is larger than what is actually seen

Posted By: bwhackd34

Re: What do your heads flow? - 07/19/12 02:34 AM

No.....the 330ish was a rough average through the port....at SSR wasn't stated......

Posted By: bwhackd34

Re: What do your heads flow? - 07/19/12 02:36 AM

Quote:

ok you gave "us"

470cfm
260fps at throat
330fps at short side
95-96% throat of valve size

you dont see that by figuring back from the velocity at the throat, and the airspeed,, that some relation can be made to the area at the short side? it can...

must be all voodoo top secret spy porting suff going on here,, magic..

your ca formula doesnt work to real world data,, it gives a ca that is larger than what is actually seen

This is what I was saying the other ay regarding we as humans and the airflow 'seeing' the CA from different perspectives....

Goodnight