EFI Intake/Throttle body info

[Outlaw440]

Here is the relation by blade cross section area solved for blade diameter.

Let's go back to the suzuki aerio engine since that seems to be merc91's favorite.

2005 Suzuki Aerio 2.3L DOHC engine = 65mm bore/60mm blade
60 mm / 140 cid = .4286 mm/cid = 129.4 mm for a 302
4.38"2 / 140 cid = .0313"2/cid or 9.45"2 = 3.47" Blade Dia. or 88.1mm for a 302-Still looks pretty darn close to 90mm don't it? And this is factory OEM non-performance emissions compliant stuff, all these cars im sure gain performance with larger TB's. Not that the performance aftermarket for suzuki aerio's is even existant for all i know, lol but the point still stands.


1995 Mercedes Benz C280 2.8L engine = 70mm bore/70mm blade
70 mm / 171 cid = .4093 mm/cid = 123.63 mm for a 302
5.97"2 / 171 cid = .0349"2/cid or 10.54"2 = 3.66" Blade Dia. or 93.0mm for a 302

1990 Toyota Corolla 1.6L DOHC engine = 57mm bore/56mm blade
56 mm / 98 cid = .5714 mm/cid = 172.60 mm for a 302
3.82"2 / 98 cid = .0390"2/cid or 11.76"2 = 3.87" Blade Dia. or 98.3mm for a 302

I can do this all day guys.

[P72Ford]

P72ford, would you like me to post up the conversions in Average Cross Sectional Area (ACSA)? Because i have those as well. ACSA is also what real engine builders are using to determine what cylinder heads, intakes are used. I simply kept it 2 dimensional to try to keep it more simple for people to follow along. I beleive you have a fairly good knowledge of math so i may post them in a moment.

You shouldn't have to ask if I want to see this ASCA stuff. Of course I do. As it is, ACSA is 2 dimensional. Area is a unit of length squared. 2D. I would certainly hope "professional engine builders" are using at least that rudimentary means. Based solely on the name, I'd assume ACSA uses arbitrary geometry, based on finding the hydraulic diameter of a cross section.

I also see you have provided some 2D data, which is nice.

As you'll recall from my earlier post, I claimed that comparing two engines is not value added. If you are familiar with the idea of diminishing returns, and can relate volumetric efficiency and overall engine efficiency to that, you'll understand why I said what I did.

Just because you compare a 2005 2.3L DOHC 4 cylinder to a 1980s (really developed in the late 60s) OHV pushrod Ford 302 V8, doesn't mean anything. The later OHC 4 cylinder is a more efficient engine, which goes without saying. Its apples and oranges.

Beyond all that, I want to know one thing...

Does anyone assume a linear relationship between TB diameter and CSA? You still are posting 1 dimensional data (in addition to 2D). Why? Is that a standard used by someone? And, if so, I am very cruious to know why someone thinks that is a reasonable assumption to make. I have a fairly decent background in fluid dynamics, compressible flow, etc, etc, and have never seen such an assumption. If there is good reasoning, I'd like to hear it. Inquiring minds want to know.

[Outlaw440]

and about me spreading BS... read your first post again and you calculations for how big a HO 5.0's TB needs to be. Thats BS, and you need to figure out how many CFM each motor needs to pull in at its most demanding point, not just CID. Which I did those rough calculations and they turned up that 65mm TB for a HO is what it needs. Theres no problem going over and throwing on a 75 from what I can see.
.

I seemed to have missed this crap. First and foremost, the CFM formulas for motors are garbage, they come from carbureted cars, which as i mentioned NEED restriction simply by their design. Even the carbureted formulas are shit.

Heres an example of the carb cfm formulas.

racing carb cfm = rpm x displacement / 3456 x 1.1

So we will use a 460 here.

I will do the race carb formula. We'll say its going to spin 6500rpm just for examples sake.

Street: 6500 x 460 / 3456 x 1.1
______2990000 / 3801.6 = 786.5 CFM.

Your thinking is the usual "if it only needs XXXX cfm " is good enough. IT IS NOT. Your thinking is so elementary its pathetic.

The carb cfm formulas are useless on EFI. Plain and simple.

You shouldn't have to ask if I want to see this ASCA stuff. Of course I do. As it is, ACSA is 2 dimensional. Area is a unit of length squared. 2D. I would certainly hope "professional engine builders" are using at least that rudimentary means. Based solely on the name, I'd assume ACSA uses arbitrary geometry, based on finding the hydraulic diameter of a cross section.

.

I added it in the post previous to this post of yours i am quoting as of now.

Just because you compare a 2005 2.3L DOHC 4 cylinder to a 1980s (really developed in the late 60s) OHV pushrod Ford 302 V8, doesn't mean anything. The later OHC 4 cylinder is a more efficient engine, which goes without saying. Its apples and oranges.

Beyond all that, I want to know one thing...

.

Apples and oranges it is not. An engine is an engine is an engine. XXX amount of cubic inches can move XXX amount of air, regardless of the valvetrain style used.

I have seen the same responses all of you have given millions of times "it only needs XXX cfm so anything bigger is pointless", "oh its not a fair comparison because its an OHC engine" that is flatout BS, it is still an otto engine and operates under the same principles.

Does anyone assume a linear relationship between TB diameter and CSA? You still are posting 1 dimensional data (in addition to 2D). Why? Is that a standard used by someone? And, if so, I am very cruious to know why someone thinks that is a reasonable assumption to make. I have a fairly decent background in fluid dynamics, compressible flow, etc, etc, and have never seen such an assumption. If there is good reasoning, I'd like to hear it. Inquiring minds want to know. .

Is it a linear relationship? That i am not 100% positive of and im not going to try and take a stab at it. Is it close? more than likely. Im sure the guys at sbftech.com could clear this up for you, as they are the ones who gave me the majority of this info.

None of this is exact science, it is the closest you can get however. Real engine builders are using ACSA (average cross sectional area) and MCSA (minimal cross sectional area), if thats what you wanted to know they are using p72ford.

The published flow numbers which are typically at 28" of water are useless when it comes to an internal combustion engine moving air on the compression stroke.

[P72Ford]

I added it in the post previous to this post of yours i am quoting as of now.

That is the same thing that I did in my first post in this thread. It makes sense.

Is it a linear relationship? That i am not 100% positive of and im not going to try and take a stab at it. Is it close? more than likely. Im sure the guys at sbftech.com could clear this up for you, as they are the ones who gave me the majority of this info.

None of this is exact science, it is the closest you can get however. Real engine builders are using ACSA (average cross sectional area) and MCSA (minimal cross sectional area), if thats what you wanted to know they are using p72ford.

It is not even close to a linear relationship, nor could it ever be construed as such, unless it was made linear via logarithmic scales. And even then, it just looks linear.

This is third grade math...

for a round CS:

CSA=pi*(D/4)^2.

When the independent varible (D; diameter) is raised to a power greater than 1... it most certainly is not linear.

The CSA methods are reasonable. I refuse to believe the diameter relation is reasonable, until I have some better evidence.

And, to reiterate, I'll say it again.

Comparing two engines tells me nothing. If I want to make a choice on what throttle body I should use on my build, I'm not going to set up a simple ratio, using a crap can 4 cylinder as the basis of comparison. My above argumanets have just been to show that if you were going to compare a throttle body to engine displacement, using a diameter would be incorrect. The area method is value added. But, I don't condone this as an accurate way to predict the actual required throttle body diameter for an engine.

I would do it the right way.

Also,

An engine is not an engine...

Taking two engines (one 2.3L 4 cylinder, and one 5.0L 8 cylinder) with nothing else in common, and saying that they should move proportionate amounts of air, is borderline ignorant.

There is alot to consider, really. There are alot of losses in an ICE... in fact they are extremely inefficient. Most of the energy is dumped out the exhaust (thermal), and wasted. The differences between a 2.3 DOHC and a 5.0 OHV greatly affect the amount of air each moves. One has nearly twice the cylinder surface area with which to deal with friction. Late model engine blocks are sometimes coated in Molybdenum to cut down on friction, as well. Then of course we come to the valvetrain, and cylinder heads, which are the true limiting factory.

An engine is going to only move so much air, no matter how big the throttle body. The camshaft profile is very important in determining that, obviously, as well as port shape, port velocity, etc, etc. All that good stuff.

To me, it sounds as though you are trying to say that if a 2.3 DOHC requires a tb of diameter d, to let x amount of air into the engine, then a 5.0 OHV should have a tb diameter of (5.0/2.3)d, to let (5.0/2.3)x amount of air into the engine. That is absolutely incorrect, for the reasons discussed above.

If that is not what you are trying to say, please correct me.

[Outlaw440]

An engine is an engine. I am not sure what the misunderstanding here is.

I am stating that a 302 has the potential to move as much air (proportionately) as the 2.3L, the 2.8L mercedes, the 3.9L V8 lincoln, the 4.0L V8 oldsmobile aurora. Which are all emissions compliant, factory stock restricted motors mind you, which are given the ample flow to operate efficiently by the factory.

The E6 headed, E7 headed 302s are by far not what i would consider an efficient motor, i am stating they (302s) have the potential to proportionately move as much air with the proper cylinder heads/intake/exhaust/camshaft etc. XXX amount of C.I.D. can move XXX amount of air, regardless if the motor is SOHC, DOHC, OHV, etc. You are not going to move proportionately as much air with factory 302 heads, there are no factory ford heads that are efficient enough for that to be possible (except for maybe cleveland heads, but i dont see many here using those). Maybe that is where the confusion is, i dont know.

I hate to bring cylinder heads into this discussion but we are talking AFR 185 (if you want to use standard valve placement, stock valve angle, inline valve stuff), TFS TW 170cc, and the now obsolete Canfield 195s, to be as proportionately efficient as other engines. I mentioned a 90mm TB and a larger intake will be valuable regardless of what heads are on the motor as long as the proper matched camshaft is used, but for a 302 to be proportionately as efficient as the engines listed it needs to be a full package (head/cam/intake/exhaust) all need to be matched components that can work in harmony. LSX and the modern HEMI engines are using this technology with what some would call massive cylinder heads. This is why the SBF performance world is so crippled with misinformation. The too big mentality has gone on for too long and i cringe everytime i see the crap getting spread around.

If you guys cannot get on page with how this works, how things work in the real world, then i will leave and you can all figure it out on your own. I posted the information in hopes of bringing some info that is usually kept under lock and key and make it more widely available. I am still seeing the corral.net, mustangforums, allfordmustangs mentality everywhere and its a joke. The info is there, what you do with it is your own choice. If you cannot get beyond the CFM flow and the "ohc engines are different" crap, then i am done trying to explain this. This stuff is common knowledge on a forum i participate on, i don't get why nobody else can grasp this simple concept.

This is why i decided not to open my own performance shop, i kept it mostly repair for the ease of it. There are too many idiots that think they know what they are doing, still want to jump back to the old CFM myths and the "low end tq", "you need restriction" crap, how can an engine make power if its being restricted? without airflow the tq is going to be sh!t. Sure the extra money i could make would be great, but i cant stand idiots, and i know i would go crazy after not long.

[87_crown_vic]

i just wanna see what the guy has built as proof of his theories. i wanna see his box panther and what it can actually do compared to his theories with no evidence.

[Outlaw440]

i just wanna see what the guy has built as proof of his theories. i wanna see his box panther and what it can actually do compared to his theories with no evidence.

I don't own a box panther, i own a 99 marquis.


I have wrenched on more windsor engines than most of you have probably even seen.

Beleive me, if a box panther could be trimmed down to 3200 pounds to meet SFI 25.2 chassis specs i would be running one. Until SFI deems it safe to be running a car that heavy at those speeds i will not be using one.

I would gladly invite anyone over my house to see what i have done, am doing, and in the process of doing. Grow the fuck up moron. Or hell, next year come out to atlanta dragway, bradenton,FL, atco raceway, epping etc. I will be making two appearances at atlanta dragway in the ORSCA Outlaw 10.5 category in a white 99 mustang and i will try to be in NMRA Pro Outlaw 10.5 for every race next year as well, i can't guarantee i will qualify for every race however as there are seemingly more entries in that class every year.

14 second cars bore me quick, 12 second cars bore me, 9 second cars even got boring after a while, you all want to discredit what i have and haven't done, THEN FUCKING COME OVER MY HOUSE RIGHT NOW, and i will gladly show you, until then, kindly shut your mouth trying to shoot down what i do and dont know. Hell, ill even take it a step further, cover the costs of diesel fuel to go out and pick your ass up and ill bring you with me to the god damn track, and you can watch every thing i do if it turns you on.

Lovely tag on this thread as well, in a tech section toboot.

[87_crown_vic]

i say you take your racing expertise over to Pirates area where you might be appreciated more and would have fun time since he races and does big things too...

http://www.grandmarq.net/vb/forumdisplay.php?f=66

[Outlaw440]

i say you take your racing expertise over to Pirates area where you might be appreciated more and would have fun time since he races and does big things too...

http://www.grandmarq.net/vb/forumdisplay.php?f=66

If thats what you would rather than so be it, i gave examples to back up my theories if you actually read anything i posted. So don't start trying to make claims that i don't know what im talking about.

I will just keep the actual tech info to myself then, and if someone wants real tech info they can PM me (like many have already), call me, email, instant message, whatever or contact me on sbftech.com. If you all are afraid to sit back and listen to the truth, thats your own problem. Forums where crap info like what gets spread around here are dime a dozen.

[P72Ford]

An engine is an engine. I am not sure what the misunderstanding here is.

I am stating that a 302 has the potential to move as much air (proportionately) as the 2.3L, the 2.8L mercedes, the 3.9L V8 lincoln, the 4.0L V8 oldsmobile aurora. Which are all emissions compliant, factory stock restricted motors mind you, which are given the ample flow to operate efficiently by the factory.

The E6 headed, E7 headed 302s are by far not what i would consider an efficient motor, i am stating they (302s) have the potential to proportionately move as much air with the proper cylinder heads/intake/exhaust/camshaft etc. XXX amount of C.I.D. can move XXX amount of air, regardless if the motor is SOHC, DOHC, OHV, etc. You are not going to move proportionately as much air with factory 302 heads, there are no factory ford heads that are efficient enough for that to be possible (except for maybe cleveland heads, but i dont see many here using those). Maybe that is where the confusion is, i dont know.

I hate to bring cylinder heads into this discussion but we are talking AFR 185 (if you want to use standard valve placement, stock valve angle, inline valve stuff), TFS TW 170cc, and the now obsolete Canfield 195s, to be as proportionately efficient as other engines. I mentioned a 90mm TB and a larger intake will be valuable regardless of what heads are on the motor as long as the proper matched camshaft is used, but for a 302 to be proportionately as efficient as the engines listed it needs to be a full package (head/cam/intake/exhaust) all need to be matched components that can work in harmony. LSX and the modern HEMI engines are using this technology with what some would call massive cylinder heads. This is why the SBF performance world is so crippled with misinformation. The too big mentality has gone on for too long and i cringe everytime i see the crap getting spread around.

If you guys cannot get on page with how this works, how things work in the real world, then i will leave and you can all figure it out on your own. I posted the information in hopes of bringing some info that is usually kept under lock and key and make it more widely available. I am still seeing the corral.net, mustangforums, allfordmustangs mentality everywhere and its a joke. The info is there, what you do with it is your own choice. If you cannot get beyond the CFM flow and the "ohc engines are different" crap, then i am done trying to explain this. This stuff is common knowledge on a forum i participate on, i don't get why nobody else can grasp this simple concept.

This is why i decided not to open my own performance shop, i kept it mostly repair for the ease of it. There are too many idiots that think they know what they are doing, still want to jump back to the old CFM myths and the "low end tq", "you need restriction" crap, how can an engine make power if its being restricted? without airflow the tq is going to be sh!t. Sure the extra money i could make would be great, but i cant stand idiots, and i know i would go crazy after not long.

Ok. You may (or may not) have a decent knowledge, but the first strike against you, as is often the case with knowledgeable people, is that you are arrogant. Nobody can learn from someone that is arrogant.

And, as knowledgeable as you are, you can't explain to me the simple reasoning that I asked for. Who uses a diameter to engine displacement ratio, and why do they use it/ think it is ok to use?

As far as the engine comparison goes...

You never stipulated aftermarket components. Now that you have, I ask you this: Why compare a stock 2.3L DOHC engine with a modified 5.0L OHV V8? It is even more nonsensical than originally thought. Apples and oranges. 1960s technology, with 1990+ technology. Of course you can make a 302 move as much air as a late model engine... but why make such a useless comparison?

If you don't mind me asking, what are your credentials as they pertain to engine building/ performance theory? I am not trying to discredit you, but rather trying to validate you. I am no engine builder, but I am a mechanical engineer, minor in math, and background in thermodynamics and fluid dynamics. I am making points merely from my experience, and using logical reasoning.

Also, I see you are from southern Massachusetts. I am from northern Connecticut, right in the river vallkey, a little north of Hartford. I'd love to see your car, and also wouldn't mind sitting down to talk some tech. Do you ever run it at Epping or Lebanon Valley?

[P72Ford]

Actually, I just thought of another point I'd like to make, as well as a correction.

In one of my above posts, I typed:

CSA=pi*(D/4)^2.

When it should be:

CSA=pi*(D^2)/4.

Thanks to Michael for catching that.

Outlaw440: You are talking about sharing what I'll call secret information. Whether it is or not (which I am not going to comment further on), you should know that when people are used to hearing something for a long time, their opinions are not easily swayed. Do not become frustrated because people are challenging your line of thought. It is only natural.

Furthermore, it gives you the opportunity to polish your ability to explain beyond a reasonable doubt.

[Heretic]

Opinions are like assholes...

Outlaw440: You are talking about sharing what I'll call secret information. Whether it is or not (which I am not going to comment further on), you should know that when people are used to hearing something for a long time, their opinions are not easily swayed. Do not become frustrated because people are challenging your line of thought. It is only natural.

Furthermore, it gives you the opportunity to polish your ability to explain beyond a reasonable doubt.

Thank you, P72.

So you are aware, I am the one who tagged this thread. I see you as trolling, only because you came in here with this "Secret info", then proceed to be a fucking asshole to everyone. I see this entire thread as you specifically wanting to cause trouble with the folks here.

I do not know all the formulas that you are spitting out, nor do I want to. The people here have there opinions, as do you. But you come here, a new user, and immediately basically tell everybody they are wrong. Most of the people here use proven combo's that are basically "Stock", and that works for them.

Your coming here and attacking people unprovoked like this is going to get a reaction, naturally. So change the way you come off, and be a little nicer to people, and your opinion/theories/facts/whatever will be heard. But don't talk to us like we are all fucking 5 year olds and then get all butthurt when we react.


/Thread.

[Outlaw440]

Thank you, P72.

So you are aware, I am the one who tagged this thread. I see you as trolling, only because you came in here with this "Secret info", then proceed to be a fucking asshole to everyone. I see this entire thread as you specifically wanting to cause trouble with the folks here.

I do not know all the formulas that you are spitting out, nor do I want to. The people here have there opinions, as do you. But you come here, a new user, and immediately basically tell everybody they are wrong. Most of the people here use proven combo's that are basically "Stock", and that works for them.

Your coming here and attacking people unprovoked like this is going to get a reaction, naturally. So change the way you come off, and be a little nicer to people, and your opinion/theories/facts/whatever will be heard. But don't talk to us like we are all fucking 5 year olds and then get all butthurt when we react.


/Thread.

I am not attacking anyone, get that straight my friend.

Sorry if i don't come off as politically correct, i never have been, never will be, if that bugs you, then tough.

My bad for responding when 87_crown_vic posted some nonsense asking me if i had built a panther. I responded to him in the same manner he jumped out at me, no more, no less. An eye for an eye.

If you want to build stock motors, then your barking up the wrong tree by even talking to me. Disregard everything in this post if you want a stock replacement motor.

I will respond to P72ford and others later tonight or tomorrow when i have time. I have to be in Maine in 4 hours.

[Heretic]

An "eye for an eye" won't get you far here. And I like the barking up the tree comment, as if you are so superior to me that I cannot even talk to you. Glad to see my "Stock" motor defined me as an inferior human being before I interacted with you.

[Outlaw440]

An "eye for an eye" won't get you far here. And I like the barking up the tree comment, as if you are so superior to me that I cannot even talk to you. Glad to see my "Stock" motor defined me as an inferior human being before I interacted with you.

I don't give a damn where it gets me.

I never said i was superior to anyone, where you got this idea is beyond me.

Never said you were an inferior human being either, maybe you have some self esteem problems if your jumping out and saying that, IDK.

Im simply stating i don't build many stock motors, therefore i am the wrong guy to ask about what should be done with a stock motor, it is not my expertise. Don't go all crazy now and take that as i think im superior, because im not and i know that.

Back with more later.