new ebay intake manifold...

[Boosted98gsx]

I tend to agree with everything you say. But, real world examples have my attention and cannot be dismissed. With your knowledge, can you show us why the magnus does so well even w/ the flaws you have brought out? You'll have my undivided attention and respect.

Because almost anything made out of sheet metal that has straight runners is going to flow better than the stock manifold on the top end.

I'm not sayin that you will not gain horsepower by using the magnus over the stock unit, but you would gain more airflow and power over the magnus by following sheer physics rather than trends.

Every automotive engineer that I've shown the mangus to has laughed at its design. Take that for what its worth.

 

[dsm-onster]

You're also need to think that at the very last stages of the "induction" cycle air is not being "sucked" in by the piston, or "pushed" in by the boost. Its actually just following the air in front of it. If you can increase the velocity in which the air enters the cylinder, more air will enter the cylinder, just because in those last seconds of the intake valve being opened, the air is still speeding into the cylinder. Basically if you are trying to get even more pressure in a cylinder than is in the manifold.

Yes, this is the very reason why high duration cams provide more peak power, generally. The intake valve is open longer allowing the air to flow as it is subject to momentum. Being harder to stop means that it is likely to contunue filling even against a "full" cylinder.

Boosted98gsx, can you give us more. This discussion is not yielding an answer. Just more questions. . .

 

[Coup D E'Tat]

Because almost anything made out of sheet metal that has straight runners is going to flow better than the stock manifold on the top end.

I'm not sayin that you will not gain horsepower by using the magnus over the stock unit, but you would gain more airflow and power over the magnus by following sheer physics rather than trends.

Every automotive engineer that I've shown the mangus to has laughed at its design. Take that for what its worth.

Alright, then why doesn't Magnus/JM/AMS/whoever use the principles of fluid dynamics? Not saying either party is wrong, I'm just wondering if maybe what works on paper doesn't work in the real world. I would think that, in this stage of the game, people would have a pretty good idea as to what they're doing.

But, then again, what do I know? The Magnus and JM make power, and ignorance is bliss

 

[dsm-onster]

Every automotive engineer that I've shown the mangus to has laughed at its design. Take that for what its worth.

It's worth almost 5 tenths on stock cams and a 2g head with a 50 trim and no other tuning. . .
See:

DSMjim

I am an engineer. And I am amazed at what mother nature shows me dispite my efforts to forecast and speculate.

 

[staticbrainwash]

Boosted98gsx, I can't believe that you are still arguing against real world results, and more R&D time than you probably realize over how something looks on paper "in theory".

You can argue all you want, but i'll take real world results over paper theories anyday. And until i see those said theories put into true application in the form of a smim (to keep the context of this thread) the rest is bunk.

 

[Boosted98gsx]

It's worth almost 5 tenths on stock cams and a 2g head with a 50 trim and no other tuning. . .
See:

DSMjim

I am an engineer. And I am amazed at what mother nature shows me dispite my efforts to forecast and speculate.

Yes, but compare it in a HIGH airflow setting where SMIM's are actually worth their weight, and see that a constant sized plenum w/o the stacks will flow more (this was proven in the DSMlink airflow SMIM tests as the venom and the Forrester came out on top with this design over the magnus).

 

[dsm-onster]

5 tenths is worth a smims weight... what's that about 50 hp or so? I have not seen the venom or forrester to provide enough flow in a broad enough range to be usable at the track or the street. Peak hp and peak airflow is nill when most of the flow doesn't come on until it's time to shift... Over what range did the venom and forrester outperform the magnus?

 

[92awddsm]

First off, everyone here needs to learn how to read. The manifold comes from Bangkok, Thailand not Taiwan.

Second, pencil pushers get on my nerves because usually, all they know is what works on paper, not in real life. Now, prove to me that a Magnus or JM manifold would be slower than a venom in the 1/4 mile. Thats all that matters to me and my 60-1 starts working when the Venom starts to fall off. Most people here that are looking at a smim is more concerned with high rpm, high airflow performance, not street drivability or lower rpm performance. If that was the case, none of us would run anything more than a 1g im.

 

[staticbrainwash]

^^ And How!

 

[GSX_RCR]

Is it me, or is that just a highly polished cast plenum? (no wonder they can make it so cheap)

And those velocity stacks....well, they look more like nuclear powerplant steam towers? The top should have a smooth rolled lip to reduce turbulence. The cast stacks have sharp edges that will just induce turbulence and reduce flow.

I'd hate to bench race, but you're better off with a stock ported manifold. But if you feel the need for a big shiny intake manifold, this will do it.

 

[darren0828]

I agree with 92awddsm. Please read before make any reply. In the E-bay statement, it stated clearly that "The manifold is manufactured locally here in Bkk Thailand". Please dont just assume every junk is made in Taiwan(just most of them). There are people who dont want to pay for real stuff, therefore there are alot of "look nice" junk trying fool people.

For this IM, it is not even a finish product(although the flange look like is for our car). You dont even know what the quality of the "finished" product will look like. This is one reason this is not a good buy.
Second, agree to GSX RCR. The velocity stack look really bad. Compare to Magnus Sheet Metal Intake Manifold, I dont really think this IM is worth that much (The price is helf of what Magnus sold) ... i will not pay more than $50 for this intake.

darren

 

[awddsm95]

Hey all,

Just figured that I would throw in my two cents, or tens of thousands of dollars I have spent on my college degree for Mechanical Engineering. After reading what has been written, and glancing at my fluids and thermo book, I have a few thoughts.

First off, I am happy to see that Boosted98gsx and a few others is approaching this from an engineering POV. I do and will back up the engineering principles that Boosted98gsx has mentioned. I would also like to point out that He has not by any means said that these SMIM's do not produce more power than factory, but merely stated that they have not been engineered to their fullest.

One thing that Boosted98gsx and other engineers like myself must come to understand that while yes, on paper these ideas can be designed to yeild an efficieny of 100%, in actual senerios, this is most of the time impossible. The Reason: there are two sides to most engineering principles/equations, the IDEAL, and the ACTUAL. Most of the calulations we do as engineers are for the IDEAL conditions. The reason that this is not completly plausible in real life is because there are factors beyond the control of an equation. One of the most important engineering principles that I have learned is that there is no sence in redesigning the wheel. For one, its not economically reasonable to design something to its 100% efficiency. That costs companys time and money. There is simply no point it it, the better approach is to take what already works and is proven, and improve it, PERIOD. If any of you would like to argue this with me, I work for an Aerospace company, and you all can imagine the percision required in aerospace design, but typically, Engineers design it so it works and lasts. There is no reason to redesign the wheel.

My opinion:
NA: (Naturally Aspirated)
A tapered plenum works wonders for a NA motor that does not have protruding "velocity" stacks if the taper is in the right place and at the correct angle. If a NA intake manifold is designed without a taper, then Velocity stacks are a great idea. Some designs use a constant plenum (either square or circular) with velocity stacks increasing in height the farther you get from the throttle body. This design is also good and can be compared to an intake manifold with no stacks and taper. The idea of Increasing stack height or a taper is to equalize the flow to each cylinder. As you can imagin if you have no taper, no stacks and a constant plenum, the #1 cylinder with draw the most "flow" due to its proximity to the TB. This makes sence, and in order to come closer to the 100% efficincy for a NA intake manifold, the best design is in my opinion either an increasing stack w/ a constant plenum or a tapered manifold with no stacks designed to insure equal flow to each cylinder. (Of course the size of plenum and runners would be determined by the size of the engine and the desired results)

FI: (Forced Induction)
Like described eariler, when it comes to design for a fluid, turblance is not the best for maximizing flow or velocity, (although it is good inside a combustion chamber for fuel ionization and burn optimization). In a FI manifold, we would like to reduce turbulance, and increace velocity. Due to the fact the air, which is a fluid, is being forced in, equal flow to each runner is acheived without the need of stacks due to the pressurization of the plenum. Unfortunattly for all of us FI guys, most companys who "design" these manifolds us a flow bench, which does not account for the pressurization of the plenum. This is the reason for the stacks or taper we see in these manifolds, they were typically designed with some engineering and the use of a Flowbench. Fortunattly, we are not traveling to outerspace, but simply down the quarter mile, and these designs do yeild extremely satisfactory results, despite the fact that the were not engineered to 100%. I have looked at many many manifolds and have said to myself that I could design it better. Although this may be true, and I do have the Fab/capabilitys to engineer them better, the gains would not be worth the time or money. If we made an Ideal manifold for an FI, it could yeild double the power of one from ams, or magnus, but most likely and in reality would not. I think that if most of the SMIM's on the market produce on average of 50-60hp without the addition of cams, a perfectly designed manifold for factory cams could yeild anywhere from 65 to 80 hp. (this is just an example)

If I were to design a FI manifold for our cars, It would most likely be a constant Tear drop shaped plenum with the runners on the flattend pointed side of the teardrop. I could post a drawling, but I refuse to draw it paint, as most of you cannot view Autodesk Inventor files. One thing to remember with all fluids is that turbulance is bad for flow, and curvature of points help flow. Air as a fluid is for the lack of better words CRAZY. It's flow responds to the slightest changes in depth, curve, gap, etc. dramatically. We have a big wind tunnel at work, as our company does wind tunnel testing, and if you have ever seen the flow of air with smoke, its crazy what .100 inch makes.

Anywho, thats what I have, I actually have more, but Ill save it for questions.

P.S. For our motors (FI), and DSM's meant for straight up speed, its Volume, not Velocity we are after.

Kyle Deiwert

 

[spoolin_turbo]

I have to agree with Boosted98gsx. And awd95 just put the sugar on top. Sure magnus makes a nice manifold. One of the best off the shelf designs out there. But it isn't flowing like it could be. Think outside the box guys. If someone doesn't make something like this I will post some dyno results with one against my magnus in a few months. It is going to cost me $1600 to have one made and flowed to match my head. It really wont be a fair comparison but it should prove something about velocity stacks and fi.

 

[92awddsm]

Hey all,

. As you can imagin if you have no taper, no stacks and a constant plenum, the #1 cylinder with draw the most "flow" due to its proximity to the TB.
Kyle Deiwert

I agree with most all but this. The #1 cylinder is farthest from the tb on both n/a and fi dsm's, both 1g and 2g. This makes the #1 cylinder fight for a clean intake charge.

Now, on paper, fluid flow looks good but has anyone taken valve overlap and reversion into consideration while trying to figure this out? This is where the velocity stacks come into play. The stack tends to seperate the reversion from the clean incoming air which in turn reduces turbulence. With just a radiused inlet, there is no divider of sorts to keep the reversion from being swapped around to different cylinders. Granted, a fully machined stack will flow better than the sharply cast counterpart, either helps reduce contamination of the incoming charge compared to an intake without stacks.

 

[Boosted98gsx]

Thanks for the backup guys. Really helps me feel better to get a bit of a flame retardant suit on this forum. It can get quite hot on the web.

 

[loweperf]

Since I have not tested this manifold I could not say one way or the other but as far as engineering goes the Magnus manifold is designed right. Time and testing has shown that the cyl. closest to the TB will have 3-5% less flow than the one at the blocked end of the manifold, therefore the decrease in volume at that end is needed to equalize flow. Also the stacks should have a nice bellmouth into the runner. Not that you guys aren't experts in your type of work but you don't have the experience in this. BTY this is not all my thoughts Please refer to "Forced Induction Performance Tuning" by A. Graham Bell page 228. I think he has more knowledge and experience in this sort of thing than all the members of this board put together.

 

[awddsm95]

I agree with most all but this. The #1 cylinder is farthest from the tb on both n/a and fi dsm's, both 1g and 2g. This makes the #1 cylinder fight for a clean intake charge.

#1 cylinder is representitive of the cylinder closest to the throttle body in my comments, not the #1 cylinder in our motors, sorry about the confusion. If you are looking at the Engine from the front of the car towards the windsheild, the order from left to right is [4 3 2 1].

 

[awddsm95]

Since I have not tested this manifold I could not say one way or the other but as far as engineering goes the Magnus manifold is designed right.

As far as this is concerned, I would have to say that yes magnus is designed based on what yeilded the best resuts for Magnus Motorsports, a 50+ hp gain or such, but who is to say that it is right. Unfortunatly, the design could be improved yeilding higher results, PERIOD. No one is saying that Magnus SMIM is designed poorly, just that it is not designed to an efficiency of 100%, which on paper is possible, yet in real life is not. There are many designs that will and do acheive the same % efficiency, but the point is that the % efficiency can be increased if all factors are taken into account. The problem is that we all have different modifications. Design changes could be made to further increace performance gains if every factor was taken into account. Such includes the cam profile, the intake temp, the material, the heat transfer from the head to the intake manifold, psia, etc.

 

[loweperf]

As you can imagin if you have no taper, no stacks and a constant plenum, the #1 cylinder with draw the most "flow" due to its proximity to the TB.

This cyl. will draw the least amount of air due to the fact airflow will try to continue in it's direction of travel. Either because it don't like to turn corners or the venturi effect of passing over the top of the stack??? Either way when it hits the wall at the closed end of the manifold air will start to stack up and feed the farthest cyl the most air.

 

[dsm-onster]

Now, on paper, fluid flow looks good but has anyone taken valve overlap and reversion into consideration while trying to figure this out? This is where the velocity stacks come into play. The stack tends to seperate the reversion from the clean incoming air which in turn reduces turbulence. With just a radiused inlet, there is no divider of sorts to keep the reversion from being swapped around to different cylinders. Granted, a fully machined stack will flow better than the sharply cast counterpart, either helps reduce contamination of the incoming charge compared to an intake without stacks.

This is exactly what I was thinking. There is alot more goin on in an intake manifold other than forward flow. Valves close and pressure increases in the runners backing up the air (like shutting the throttle plate while in boost). Also, valve overlap and hotside pressure can cause reversion. With long runners found on a stock manifold, such nuances probably won't be noticable as the elasticity of air gives us time to reach a state where the intake valves are open AND the exhaust valves are closed IF enough distance is maintained.

So in all, wouldn't it make sense that the negative effects of the air obstruction be nulled by the positive gain of harnessing reversion? The stacks are a neccesary evil to combat a far more detrimental foe. Reversion can kill high end performance. Retarding your exhaust cam a few degrees proves this. I consider reversion more destructive to flow than most obstructions.

 

[baby huie]

i want to start off by sayign that i was in a hurry and i ant worring about my spelling

ok not be be a ass hat here but i think that many tests and re designes were put into the amkeing of the proven manifolds out on the market. i know a company like magnus wouldent put a product on the maket with out proving that it works. now my thing to do on this is that if some one on here is a auromotive engineeer and is makeing the big dollers buy 2 of the dam manifolds leave one stock and take the other to the cnc machine cut the manifold in half and use the cnc machine to mill the stacks offf then flip the thing over and cut off the intake tubes. now take the same machine and alumimum and cut out new tubes that u think are better and weld them together. now go to the dyno andd test the fact. i dont see whi you people are arguing about things that people are to cheep to test. i also have done aeromotive engineering and have worked with carbon fiber but it doesnt mean that what works in theroy is gonna work on the car.

i am sorry i think that being a designer and what actually works in the real world is two different things. i have worked in a dealership and have seen the type of shit engineers do and have to come back and bandaid because they didint do it right the first time. i ahve also saw the designes that work when u get them into the car but if u ever have to work on them is almost imposible. now just as a example ford taurs trannys have lubercation probelms and they are burning up now as technicions we have to rip them back out and re build them and enlarge the oil gallires to make them run right. now another example is the nissan titan with is a huge truck with basically honda rotors. they are haveing major problems with warpage and the engeneers that are so amart didnt think of that and nw there scomeing back for people hat work in the real world to fix.


I will also say that if some rich peron on here wants to providethe cash i can do this test and modify the plentium how ever these engeeniers think would be best and do the wrench work to test them.

 

[dsm-onster]

I'll put my title on the line and wager that Magnus had already done the testing of a "properly" radiused runner vs. propery radiused velocity stacks.

 

[92awddsm]

I'll put my title on the line and wager that Magnus had already done the testing of a "properly" radiused runner vs. propery radiused velocity stacks.

If they hadnt, they never would have decided to install the velocity stacks. Im also sure it was all covered in their r&d.

 

[92tsifwd]

Ya, I finally got my dejon intake on and other than the fitment issues it looks pretty nice on there. I have not got it running yet though.

 

[tstkl]

as most of you cannot view Autodesk Inventor files.
Kyle Deiwert

I can. I've got autocad 2006 and inventor, and I KNOW HOW TO USE IT TOO

too bad being able to draw anything I want in autocad isn't a welling paying job that I know of. I always hated inventor, just because it was a change from what I was used to. right clicking and pressing done got old very fast. (or as one of my peers said it best, "NO, you have to right click and click DOUGH'N")

sounds like your discribing the venom manifold kinda. The teardrop design is kinda there until you get to the flat face where the phenlum meets the runners. but maybe I have your idea screwed up in my head.


btw paint rocks