home made sheet metal intake

[sparky1987]

All this custom parts being made 2012 is going to be an awesome year for the dsm crowd.

 

[Gamble97]

How did you make the motor mount? Is that SS or mild? How thick is the metal of the round and the flat stock? I like it.

 

[9!'clipseDOHC]

I finsh it yesterday, I think its around 300 C.I. its getting ran regardless. If its a little big side thats alright i'll just have to get to finshing my high compression 2.3L (seems like a good excuse anyways)

Very interesting, look phenomenal!

 

[RipperXX]

Thread is full of win. (just needs test results)

 

[H@xtGSX]

Wow, I wish I could weld 1/2 that cleanly. Mine are always bigass gorrilla welds that always have crap blasted out around the bead line. Very nice work.

Since we are talking manifold design, I have a question for you guys. I have been thinking about the flow pattern seen in most upper plenums I've seen and there always seems to be that dead end stop at the back, and the air must take a hard 90 degree turn at high speed to get down the runners... Wouldn't a totally smooth and curved path be optimal, just as how you treat intercooler pipe? Wouldnt a tubular intake with smooth transitions, much like a tubular exhaust header, provide a faster response? I would think preventing abrupt changes in direction and high velocity flow in smooth tubular pathways would at least make a good street manifold for people who wanted lower rpm peaks. Has anyone seen anything like that or know why it is less efficient than the beer barrel with legs looking smim's?

I am very seriously thinking about trying this and have been trying to figure out what I am overlooking for a month.

 

[sparky1987]

The end that is in question would serve best with a dome on the end but there is down falls to that as well with the curve of the dome it can cause the air to reverse in direction. Or atleast that's how I would undertand it but it is definetly a good question.

 

[H@xtGSX]

I would think that there has to be a reason I've not seen one like that because I'm sure someone before me has thought the same thing. I just can't think of where the drawback to that would be...

I showed a friend of mine who works for a company that makes nuclear coolant piping and fuel containment systems your manifold pictures. He's nuke weld certified and is one of the best I have seen for doing clean, complex welds and he said he couldn't have done any better than what you did working freehand. In fact, he said he'd really have slow down, lower the amps, and really concentrate on precise feeding and draw to duplicate that even of a bead run on aluminum. He was impressed, so I'd say you have the vast majority of welders beat quality wise if you can routinely weld AL like that. If you made parts, I would buy them based on that evaluation. Keep it up!

 

[sparky1987]

Thanks a ton man that's definetly a compliment that goes very far. Granted I weld aluminum almost all day every day at work. But thanks again man.

 

[H@xtGSX]

Something I found interesting in relation to flow characteristics and manifold design:

Intake Manifold Design | HorsepowerCalculators.net

Also, as to what a purely tubular IM would do, that idea would be much better than stock for low end torque, but the lack of an air reservoir in the form of a plenum would choke the motor at high rpm, at least in theory, but force feeding at higher pressure I would expect to counter that effect. Even then, the design aspect for a transverse engine is a nightmare unless you have manifold past the firewall, behind the dash. I spent 3 hours on AutoCAD last night trying to figure out a way to keep the runners equal length and fed equally from the throttle body, incorporating a 1.5L tubular plenum fed inline with the runners... With the space we have, I can only find 1 way to do it, and that's route the intake down toward the rear engine mount, curve up to centerline between 2 & 3, then fork the piping to the cylinder in a fan shape. It would be a really difficult fit, make a custom throttle cable assembly mandatory, and place the throttle body in an awkward position if you needed access to it. I don't believe the gain in the low end torque would be worth the trouble. The design shown above with it fanning down from the top of the motor is the other way to do it, if you don't mind it sticking up through the hood. It would be easier to make a staged twin turbo, which would deliver a lot bigger gains. So instead of trying to reinvent the wheel, I looked into how side mount intakes are designed. There are a few tweaks mentioned in that article I think you may be interested in you could incorporate easily to your current project.

 

[turboglenn]

H@tGsx, good info, although based solely on "thoughts" alone you would hope/think that if you could do it like a long tube header with a "collector" about 4" in diameter and long enough to be about 1.5 - 2 liters displacement that the speed of the air from the turbo and it not having to deal with filling a plenum and all the air speed changes that take place inside of one that it would easily perform up the levels of the best SMIM. but that's thinking in the aspect that the engines sucking from the plenum which is no where near "ideal" for airflow and the turbo at the same time is filling the plenum and with it's back wall and 90* runners is also far from ideal in airflow aspects putting strain and more backpressure on the turbo (a.k.a boost)

It would seem to be almost the flawless perfect design given that all runners were equal length and had similar bends from the collector/plenum into the intake ports (i'm picturing it where the runners come out and turn to the passenger side forming themselves into the collector) but actually drawing/sketching it up you quickly realize the nightware it would be to get right .

But i still think with air speeds over 140mph from the turbocharger with no walls, pooling areas, or 90* sharp routes to have ot be drawn through it would seem that airflow would be superior in all RPM's and bothtorque and HP would gain from the velocity of the air as well as no restiction to the raw CFM up top (not even considering boost as it's only a result of the air an engine "cant breathe/move")

I bet something like this done on somethign like that 4g63 rail car drag car (the 6 second one) would be not only a pimp testing ground but might actually show some sweet results.. honestly look at any SMIM (except a few really nice newer ones) as well as looking at the stock IM's of our and other performance 4 bangers, they're hardly what you'd picture for efficient air flow

 

[H@xtGSX]

Agreed. The tubular idea would in most respects be similar to an equal length exhaust header, but like you also have seen, it is a really hard concept to fit in our engine bays. The efficiency of what we are theorizing here should in all respects be much higher than a traditional smim since the dead ends and hard 90's are eliminated, but it isn't something we'll likely see purely because of fitment problems. The aspect of angling and progressively reducing the plenum to feed runners also approaching at an angle though is completely feasible, and I am curious as to why we have not seen something like that in aftermarket intakes. It at least would eliminate the 90 degree turns and tighten up the shotgun-like pattern of the incoming air to a more linear pathway.

I'm sitting at my desk right now using AutoCAD and was just thinking that if the throttlebody were moved back along the uicp, that would effectively make the intake pipe behind the throttle an inline plenum which could then feed a manifold of equal length tubes from a topwise angle without having to cut into the firewall or hood... Or at least that is what the computer is telling me. Now I am going to have to tinker around with it some more.

The one thing physics wise I can see maybe detracting from the efficiency of doing a tubular system would be the increase in friction from air interacting with the walls of the pipe, though I have no idea what that increase would be or if it would be enough to be a significant consideration.

 

[sparky1987]

I wish I had cad at home so I can fine tune my design. I only have limited use at work and thats not often. I will definetly read through that link to see what I can do to continue to make forward changes to my current project.

I think I might have a simple solution to what you're thinking and ill try to do a hand drawn rendering of what you're thinking.

 

[turboglenn]

Agreed. The tubular idea would in most respects be similar to an equal length exhaust header, but like you also have seen, it is a really hard concept to fit in our engine bays. The efficiency of what we are theorizing here should in all respects be much higher than a traditional smim since the dead ends and hard 90's are eliminated, but it isn't something we'll likely see purely because of fitment problems. The aspect of angling and progressively reducing the plenum to feed runners also approaching at an angle though is completely feasible, and I am curious as to why we have not seen something like that in aftermarket intakes. It at least would eliminate the 90 degree turns and tighten up the shotgun-like pattern of the incoming air to a more linear pathway.

I'm sitting at my desk right now using AutoCAD and was just thinking that if the throttlebody were moved back along the uicp, that would effectively make the intake pipe behind the throttle an inline plenum which could then feed a manifold of equal length tubes from a topwise angle without having to cut into the firewall or hood... Or at least that is what the computer is telling me. Now I am going to have to tinker around with it some more.

The one thing physics wise I can see maybe detracting from the efficiency of doing a tubular system would be the increase in friction from air interacting with the walls of the pipe, though I have no idea what that increase would be or if it would be enough to be a significant consideration.

ya know,i've been waiting on a good reason to use the intake manifold flange i hand milled free hand fro 1/2" 6061 T6 aluminum.. I think i might start playing with some ideas based on what you guys can sketch, what i'm thinking of and what will fit in the engine bay.. really there's a few ways to make it cram in there

Iuf you used linear smooth radii (sp?) the tubes just like a EL header could snake a good little bit to help set the plenum back a little ways and in my 2g with the battery moved, if i take the cruise out there would be more room to snake some piping in there, but i'll have to try and source some 4 or 5" aluminum pipe for the plenum/collector, then either go nuts with some mandrel bent 1.5" Al tubing or snalke some out of light 7* angle cuts and start piping something together..

this is more motivating to get to work on than just finishing the plain SMIM i had milled the flange for and made a plenum for some 3 years ago now (got bored of it and left it aside )

But if i can put something sensible looking together in my head and mocked up in the engine bay i might give this a go

 

[H@xtGSX]

Good. I've literally been thinking about this for a month, so I would like to see if it would be an improvement also. I'm drawing a 3d cad drawing of a basic design in rough dimensions right now. If we get a concensus, at least we know Sparky can do a damn good job welding it up.

 

[sparky1987]

Im down to weld all kinds of nonsensical things.

Okay forgive the crudeness of my drawing but the number 4 runner and the main plenum are 1 piece and the other 3 runners have the same radius as the 4th runner. Obviously the air flow follows the arrows. Something similar to what you're thinking about?

 

[turboglenn]

sounds like i'm getting comited by my own curiosity, sensoe of adventure and desire to do something different from the masses that pic is sorta what i am thinking in the main scheme, but i will have to wrap the 3 and 4 tubes backwards a bit and "cram" the plenum area back over top of the runners a bit.. will have to run in more of a 3 dimensional aspect of a build to fit the tubing lengths and plenum in such a tight area.. I'm thinking like 22" runners if you count plenum wall space, which in a setup like this you would have to count plenum wall since it would be a shared continuous path

talk about torque, velocity and even a great scavenge if you were to need it

 

[sparky1987]

So my obscure drawing is close woohoo. The only problem would be getting the runners perfectly positioned and this design would possibly work if the runners were even only 6 inches long or so due to the non existant straight on ends in the plenum with just bends cut to fit and at the right radius and the runners just go straight on to the head. This would help with the more even air flow. The even better way to do it is if the runners started out at like 2.5 maybe 2.75 inches and tapered to the port size. I do remember from school that where volume decreases velocity increases. Which would allow for even better atomization of the fuel air mix and possibly less boost lag and faster revs?

 

[turboglenn]

My biggest curiosity in this is the effects of harmonics and runner tuning since the runner is plenum and vice versa so to speak in this design. normally it's said to tune for the third wave harmnoics for a nice solid and wide upper RPM power band and i'll be honest i do not understand physics that well, i try, but haven't had the teaching and just get lost at points. but with no "end" of the runner and no sectioned off 90* fit up "plenum" where do the harmonics then run to, would it just be the throttle body at that point? And if so, the variations and tuning you could have possible if the TB was mounted on a piece of pipe the same ID as the plenum but mounted on silicone tubing so that it could be positioned back and forth say 6 inches total depending on what piece of silicone you used, this could be very versatile. but then again i could be a complete idiot dreaming something some one else has already proven to be trash, but you know what.. it's our/my dream time right now so might as well have fu with it

 

[H@xtGSX]

Yes, the throttle body position would become the harmonic balancing factor in taking advantage of any rebound off of pulse waves front the valves. Honestly though, pulse wave induction in a forced induction motor really means jack schitt, IMO. Laminar flow and velocity in relation to volume under pressure is what we are dealing with. What we are aiming for should be equal distribution of energy provided by the turbo in a synchronized manner, so no one piston is out of balance.

What you have drawn there is still essentially a side mount. What I am talking about, each runner will be fed at the exact same time in the path of travel for the air. I have a partial conceptual drawing done and will show you what I am proposing sometime tomorrow. Think big plenum pipe forks to 2 runners, which then each fork again to feed each cylinder, and is fed from above where our stock plenum is now. It CAN be jammed in that space. AutoCAD doesn't lie if given good values, and I actually cut my rough measurements short to allow for a little tweaking... I can still make it fit with commercially available mandrel bent tubing. I will finish up the conceptual in the morning.

I am very happy to have a couple other skilled and experienced people thinking along the same lines. It's true that the more brains you have focused on an objective, the faster it'll become reality if the dedication is complete. This is mad scientist stuff car geeks live for. Though, the REAL science behind this has been done, proven, and is used in the most powerful cars driven today. The problems is most people will kill themselves in a hurry with a truly powerful car.... Especially if it has turbo lag.

 

[turboglenn]

Yes, the throttle body position would become the harmonic balancing factor in taking advantage of any rebound off of pulse waves front the valves. Honestly though, pulse wave induction in a forced induction motor really means jack schitt, IMO. Laminar flow and velocity in relation to volume under pressure is what we are dealing with. What we are aiming for should be equal distribution of energy provided by the turbo in a synchronized manner, so no one piston is out of balance.

What you have drawn there is still essentially a side mount. What I am talking about, each runner will be fed at the exact same time in the path of travel for the air. I have a partial conceptual drawing done and will show you what I am proposing sometime tomorrow. Think big plenum pipe forks to 2 runners, which then each fork again to feed each cylinder, and is fed from above where our stock plenum is now. It CAN be jammed in that space. AutoCAD doesn't lie if given good values, and I actually cut my rough measurements short to allow for a little tweaking... I can still make it fit with commercially available mandrel bent tubing. I will finish up the conceptual in the morning.

I am very happy to have a couple other skilled and experienced people thinking along the same lines. It's true that the more brains you have focused on an objective, the faster it'll become reality if the dedication is complete. This is mad scientist stuff car geeks live for.

Ok, it's decided YOU are the brains of this operation , I read that first paragraph and heard my brain let a tiny fart out my ear, clearly above my nowledge level/understanding

I can handle fab unless some one else has that covered. But, i have that under control if needed or the only one with the means

I guess i wasn't thinking a full 1 into 2 into 4 split, but rather a main plenum forking off each of the 4 legs directly with them being snaked to allow fitment as needed but i'm interested in this CAD rendering (i have alibre design but i'm hardly "skilled" at it,

so would i be best to just attach the TB directly to it rather than to a flanged plate and having flanged plenum/collector for tuning length from TB to valve face/backs??

seems if tuning for harmonics isn't important than we can take care of overall runner length tuning by adjustment to plenum/collector length.

also i have a CRUDE sketch on paper of my thougts, it's tighter conrfied, twisty and turny with extra length on the 1&2 runners to match what's needed to put 3 & 4 into place.. the plenum would sit as normal placement, tubes for 3 n 4 come from the closest to keep short and snaked to their respective cylinders, then 1 and 2 runners taken from where is left after 3/4 have been run and snaked to equal the length req'd to fit 3 and 4 into place having not done any math on this literally the collector can be pictured as a 2 liter soda bottle with the top cut off and a TB plate there, and the 4 feet on the bottom of the bottle extnding into the cylinder runners.. A couple of braces for strength, add some ports for boost and vac and viola...i'll be done by 7am tomorrow j/k

runner length though, this one has me wantint to take two paths, since there's no 90* plenum joint i think back to the torque of the 5.0 liter and it's 22" runners, but thinking of high RPM balance, then we would think maybe taking them down to between 12 and 16" length 1.5" nominal or OD tube .090 - .125 wall.. I just wonder how much of the runner length factor of norm that we can negate with this smooth flowing design that incorporates the plenum to the runners and vice/versa and how much plenum size/length factors into actual sepoerated runner length effects and from there just which way to go.. more velocity from length = torque, more velocity is a better charge = more combustion = faster spool... then being a completelysmooth flowing deisgn how much of the factor of needing a LARGE plenum with large short runners in order to feed it's needs are we able to make up for or negate again by the factor of un-impeded airflow and speed from the turbo/IC pipes can we take advantage of??? ANd how much help in each are we getting by blending the two major sections of the piece to share in each others work????

I would think this would be an awesome system to be hotpiped where no FMIC is there to rob airspeed from the charge, normal intake velocity of an NA engine is about 120 MPH, and i'm sure we could easily exceed that with some 2.5" pipe shortes route from turbo to intake with a good 18-24" os straight path before throttle body entry (of course as you know the 18-24" is about minimum for tht size pipe to get a good airspeed increase and stabilization of flow)
this is a brain tickler for sure


P.S> anyone got a keyboard that hasn't had water spilled in it? mine sucks to use, certain buttons don't work, some make tihngs that aren't what they're labled

 

[H@xtGSX]

I am usually the nutcase redneck engineer in a room full of stuffy stick-up-their-ass mining engineers that actually winds up making the rediculous crap they come up with work, so being the "brains" would be an honor. If you saw me in real life, I can promise you that "smartass engineer" is not the first thing you'll think. I worked construction and was a military combat comms guy for many years... That is how I paid for these "brains".

 

[turboglenn]

I am usually the nutcase redneck engineer in a room full of stuffy stick-up-their-ass mining engineers that actually winds up making the rediculous crap they come up with work, so being the "brains" would be an honor. If you saw me in real life, I can promise you that "smartass engineer" is not the first thing you'll think. I worked construction and was a military combat comms guy for many years... That is how I paid for these "brains".

How we apear and how we are engineered are rarely related enough to tell when you get into people who think outside the lines of everyday norms. Most take me for a desk jockey/engineer (was my major efore the accident though) and in fact i've owned and worked construction comapnies for a good majority of life and either by trade or hobby have always been a wrench turning mad scientist machinist my whole life

Most people honestly say if they had to guess by looking at me that i'd be a cop.. not sure how to take that one

 

[H@xtGSX]

.... I don't think that is a complement either.

Truth of it is I have 2 degrees and look like a dirty meth cooking trailer park kingpin. I work on merit and if that isn't enough, then I walk. I can and will support myself and my family corporately or self employed. Been there, done that in both circumstances.

My MAIN interest underlying all of this is SELF SUFFICIENCY. I am a huge advocate of DIY life and 100% believe that the more you know and can do in a physically independent yet productive environment, the better off you are regardless of finacial standing. I am fairly well off because I can sell myself well, but I do not trust or depend on a company to take care of me.... Especially if the bottom line is effected.

Independence is priceless.

 

[turboglenn]

.... I don't think that is a complement either.

Truth of it is I have 2 degrees and look like a dirty meth cooking trailer park kingpin. I work on merit and if that isn't enough, then I walk. I can and will support myself and my family corporately or self employed. Been there, done that in both circumstances.

My MAIN interest underlying all of this is SELF SUFFICIENCY. I am a huge advocate of DIY life and 100% believe that the more you know and can do in a physically independent yet productive environment, the better off you are regardless of finacial standing. I am fairly well off because I can sell myself well, but I do not trust or depend on a company to take care of me.... Especially if the bottom line is effected.

Independence is priceless.

coldn't be put any better, yet no one hardly ever understands what i mean when i say to them to never stop learning as the more trades/skills and tasks you're able to handle on your own the more valuable you are, not only to employers but to your own life and future..great minds eh?

anyway.. i will make anyone a friend, i judge no one based on apearances (ok, well a cop uniform tells me we probably aren't having a good conversation and a gang/crip/blood outfit tells me i probably don't wantto be your friend but you get what i mean

 

[sparky1987]

Okay I think I have it. The 3g eclipse with the sohc 2.4 has an intake very smilar to what your talking about with the header like intake but I do believe they are not equal length.

Im down to fab up something insane. My car is down right now due to tuning issues and the gremlins that have started to show themselves. But im down to use my car for fabricating purposes.