# 1.8T Intake Manifold design and construction. **URL:** \ **Category:** Shift518 Automotive\ **Created:** [January 11, 2011, 9:12am UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373 "2011-01-11T09:12:22Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![KrazyKid](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/krazykid/32/6371_2.png) [@KrazyKid](https://forums.speedlife.net/u/KrazyKid)\ **Post date:** [January 11, 2011, 9:12am UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/1 "2011-01-11T09:12:22Z")
This thread I will talk about how we are building the intake manifold for a 1.8T VW cylinder head. One of the many custom pieces going into the Jetta race car: _[http://shift518.com/showthread.php?t=20487](http://shift518.com/showthread.php?t=20487)_ Starting with what pieces I know I wanted to run; AEB large port runners, 75MM throttle body I got to crunching some sketches in SolidWorks. Solid works is nice because it allows you to quickly design the manifold, see your ideas in 3D and catch any physical design flaws quickly, prior to eating up materials and time. Also included in SolidWorks is the Flow Simulation tool. This allows you to flow test the parts with many different variables, to get a good idea of how the manifold will act in the real world. You can animate it also, and with inputting the cam profiles, timing, RPM, etc. you can actually open and close the “lids” on each runner just as an intake valve would on a motor! Now to start this, I am by no means an expert at Solid Works, mechanical engineering, or intake design. This is the first manifold I will produce from scratch, so i am way behind the 8ball here, but I have been researching this for a few months now, and reading ALOT of information about this entire process. If anyone has even gotten the chance to use Solid Works, it will take you a week to make a simple bolt! Lots of seat time is required to fully understand it. BUT with some friendly tips from friends (BoxerSix and Mafdark) I am getting the hang of it. So lets get to the good stuff. Started off by going shopping. Ross Machine Racing sells all kinds of stuff to build an intake manifold from scratch. I picked up some 1/2" flat stock for the plenum floor, a 2 foot section of their 5" D shaped plenum, some 1/2" stock for the TB plate and a D shaped end cap. I knew I would need an AEB intake manifold to start with. Idea is to simply use the German engineering they already put into it and hack the top off it! One pass across the band saw and i had just the runners left. After that we machined a slight recess into the 1/2" flat stock to position the runners in and help weld in position. At this point I had to design the plenum. Now allot of people out there just weld on the D shape plenum cap the end and slap a TB flange on it and call it a day. Sure this will increase the volume of the intake but how equal will the runners flow? Some good reading material with just this information is here to give you a good idea: _[http://forums.vwvortex.com/showthread.php?3098525-](http://forums.vwvortex.com/showthread.php?3098525-) **1.8T-Intake-Manifold-Test-Results** _ Notice the Homebrew AEB lower + RMR D plenum. Total flow is much higher than stock but look at runner #1, its seeing far less flow than the other 3, and even they aren’t very close together. That would create a slightly richer combustion in cylinder 1. So this is where SolidWorks comes into play. I designed the manifold with the AEB lower and the simple D plenum on top and added a 75MM TB to it for an inlet. This is what it looks like. The inlet boundary condition is set to 10lb/s and the outlets are set to ambient pressure. ![http://i278.photobucket.com/albums/kk94/kkkustom2/justtheDplenumontherunners.jpg](http://i278.photobucket.com/albums/kk94/kkkustom2/justtheDplenumontherunners.jpg) Notice the turbulence and the uneven flow into the runners. Now look at what just the tapered plenum after runner #2 and a .5 deg angle on the throttle body does for things. ![http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake895degtbanglefrontview.jpg](http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake895degtbanglefrontview.jpg) Same taper on the plenum for the rest, just changing the throttle body angle +2 deg or so each time: 88 Deg ![http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake88degtbanglefrontview.jpg](http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake88degtbanglefrontview.jpg) 85 Deg ![http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake85degtbanglefrontview.jpg](http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake85degtbanglefrontview.jpg) 82 Deg ![http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake83degtbanglefrontview.jpg](http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake83degtbanglefrontview.jpg) 81 Deg ![http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake81degtbanglefrontview.jpg](http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake81degtbanglefrontview.jpg) 79 deg ![http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake79degtbanglefrontview.jpg](http://i278.photobucket.com/albums/kk94/kkkustom2/Newintake79degtbanglefrontview.jpg) You can see how there is a “happy medium” with the throttle body angle. I am thinking between the 85 Deg and the 83 Deg ones would be the best. Here are the numbers for the surface goals I set too help prove the changes. ![http://i278.photobucket.com/albums/kk94/kkkustom2/798183data.jpg](http://i278.photobucket.com/albums/kk94/kkkustom2/798183data.jpg) ![http://i278.photobucket.com/albums/kk94/kkkustom2/8588895justddata.jpg](http://i278.photobucket.com/albums/kk94/kkkustom2/8588895justddata.jpg) I will pick this up in the next few days. I am finishing up the intake floor tonight by smoothing the transition into the runners and adding some material where its needed. Once that’s finished I am ready to make the final cuts and weld the rest of the plenum up. Adam, Mike & others… please feel free to chime in if you see some flaws or think I am on the right path. ---
**Author:** ![bennyfizzle](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/bennyfizzle/32/6291_2.png) [@bennyfizzle](https://forums.speedlife.net/u/bennyfizzle)\ **Post date:** [January 11, 2011, 9:18am UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/2 "2011-01-11T09:18:23Z")
nifty ---
**Author:** ![Murrdog9000](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/murrdog9000/32/6391_2.png) [@Murrdog9000](https://forums.speedlife.net/u/Murrdog9000)\ **Post date:** [January 11, 2011, 9:23am UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/3 "2011-01-11T09:23:19Z")
sweet colorings ---
**Author:** ![KrazyKid](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/krazykid/32/6371_2.png) [@KrazyKid](https://forums.speedlife.net/u/KrazyKid)\ **Post date:** [January 11, 2011, 9:26am UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/4 "2011-01-11T09:26:14Z")
See how I kept them inside the lines too! Damn i am getting good! ---
**Author:** ![jordanEBP](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/jordanebp/32/6447_2.png) [@jordanEBP](https://forums.speedlife.net/u/jordanEBP)\ **Post date:** [January 11, 2011, 9:52am UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/5 "2011-01-11T09:52:09Z")
impressed ! deff keep us up to date 🙂 ---
**Author:** ![imported\_ST4TUS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_st4tus/32/6290_2.png) [@imported\_ST4TUS](https://forums.speedlife.net/u/imported_ST4TUS)\ **Post date:** [January 11, 2011, 10:18am UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/6 "2011-01-11T10:18:17Z")
can you post up some isometrics? (hidden lines visable & shaded with edges) Solid work (no pun intended) for someone who claims to be a n00b with SW youve got PM ---
**Author:** ![stockcarboy](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/stockcarboy/32/6303_2.png) [@stockcarboy](https://forums.speedlife.net/u/stockcarboy)\ **Post date:** [January 11, 2011, 10:21am UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/7 "2011-01-11T10:21:49Z")
i can do that too. ![http://i51.photobucket.com/albums/f396/jennyg772/crayola.jpg](http://i51.photobucket.com/albums/f396/jennyg772/crayola.jpg) j/k looks awesome ---
**Author:** ![LKSi](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/lksi/32/6316_2.png) [@LKSi](https://forums.speedlife.net/u/LKSi)\ **Post date:** [January 11, 2011, 10:23am UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/8 "2011-01-11T10:23:55Z")
Interesting so far… don’t forget to build an extra v6 manifold while you’re at it ---
**Author:** ![AUDI\_JAY](https://avatars.discourse-cdn.com/v4/letter/a/898d66/32.png) [@AUDI\_JAY](https://forums.speedlife.net/u/AUDI_JAY)\ **Post date:** [January 11, 2011, 10:27am UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/9 "2011-01-11T10:27:27Z")
solid work buddy…btw i will be hitting you up soon for a lil project for the s4 ---
**Author:** ![Alpine](https://avatars.discourse-cdn.com/v4/letter/a/4da419/32.png) [@Alpine](https://forums.speedlife.net/u/Alpine)\ **Post date:** [January 11, 2011, 10:27am UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/10 "2011-01-11T10:27:50Z")
You can get, like, four people completely stoned with that thing. ---
**Author:** ![Mk4\_30R\_Ban](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/mk4_30r_ban/32/6347_2.png) [@Mk4\_30R\_Ban](https://forums.speedlife.net/u/Mk4_30R_Ban)\ **Post date:** [January 11, 2011, 12:29pm UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/11 "2011-01-11T12:29:43Z")
i cant wait to see you compare yours to an SEM on the same setup at the same manifold pressure… that would be the best test. ---
**Author:** ![KrazyKid](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/krazykid/32/6371_2.png) [@KrazyKid](https://forums.speedlife.net/u/KrazyKid)\ **Post date:** [January 11, 2011, 12:41pm UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/12 "2011-01-11T12:41:49Z")
> [@Girl Scout Cookies](https://forums.speedlife.net/t/girl-scout-cookies/38612/54): > > i cant wait to see you compare yours to an SEM on the same setup at the same manifold pressure… that would be the best test. Honestly I would LOVE to. I will say it here, I honestly dont stand a chance I assume. I have -$1029,000 invested into the R&D on this bad boy, and SEM has to have at least $1 behind theirs! so I assume I might loose that battle. BUT holy shit would it be cool if I came in a close second, or actually turned out better! Once its done, I honestly would like to find someone willing to let me install an SEM on my car while its on the rollers and do a legit test. That would be cool as shit. And thanks for the kind regards everyone who commented as well. :number1 ---
**Author:** ![DeathbyRT](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/deathbyrt/32/6648_2.png) [@DeathbyRT](https://forums.speedlife.net/u/DeathbyRT)\ **Post date:** [January 11, 2011, 12:43pm UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/13 "2011-01-11T12:43:30Z")
God damn dude. You are crazy with this shit. Whatd id give to have a sheet metal intake with longer runners on my car. ---
**Author:** ![KrazyKid](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/krazykid/32/6371_2.png) [@KrazyKid](https://forums.speedlife.net/u/KrazyKid)\ **Post date:** [January 11, 2011, 12:44pm UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/14 "2011-01-11T12:44:45Z")
> [@If you could go back or forward in time, which and why?](https://forums.speedlife.net/t/if-you-could-go-back-or-forward-in-time-which-and-why/38656/3): > > God damn dude. You are crazy with this shit. Whatd id give to have a sheet metal intake with longer runners on my car. About $500? OBO :ninja ---
**Author:** ![DeathbyRT](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/deathbyrt/32/6648_2.png) [@DeathbyRT](https://forums.speedlife.net/u/DeathbyRT)\ **Post date:** [January 11, 2011, 12:56pm UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/15 "2011-01-11T12:56:07Z")
If you can make one for 500$ ill pay you cash tonight, buy you a steak and a 36 pack of whatever beer you like. ---
**Author:** ![johnnyk](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/johnnyk/32/6480_2.png) [@johnnyk](https://forums.speedlife.net/u/johnnyk)\ **Post date:** [January 11, 2011, 12:57pm UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/16 "2011-01-11T12:57:51Z")
damn thats nothing but impressive ---
**Author:** ![Mafdark](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/mafdark/32/6322_2.png) [@Mafdark](https://forums.speedlife.net/u/Mafdark)\ **Post date:** [January 11, 2011, 1:38pm UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/17 "2011-01-11T13:38:01Z")
I love it when people dig into some thorough research before starting a project. Nice work. I would like to point out one thing though, your current simulation appears to assume that the each intake port will be open each at the same time when in reality that’s not the truth. Its quite a bit more complicated to get the behave correctly (not to mention to collect and input all the data) but in the end it will give you more accurate results. Here is a good example of what I’m talking about: [http://www.youtube.com/watch?v=vIxK6K-XSGU&feature=related](http://www.youtube.com/watch?v=vIxK6K-XSGU&feature=related) another: ---
**Author:** ![KrazyKid](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/krazykid/32/6371_2.png) [@KrazyKid](https://forums.speedlife.net/u/KrazyKid)\ **Post date:** [January 11, 2011, 1:44pm UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/18 "2011-01-11T13:44:54Z")
> [@Cars for scrap prices](https://forums.speedlife.net/t/cars-for-scrap-prices/38657/7): > > I love it when people dig into some thorough research before starting a project. Nice work. > > I would like to point out one thing though, your current simulation appears to assume that the each intake port will be open each at the same time when in reality that’s not the truth. Its quite a bit more complicated to get the behave correctly (not to mention to collect and input all the data) but in the end it will give you more accurate results. > > Here is a good example of what I’m talking about: [http://www.youtube.com/watch?v=vIxK6K-XSGU&feature=related](http://www.youtube.com/watch?v=vIxK6K-XSGU&feature=related) > > another: > [http://www.youtube.com/watch?v=\_M4H\_3IKvTY&feature=related](http://www.youtube.com/watch?v=_M4H_3IKvTY&feature=related) BALLS, I knew you or Adam would bring that up! yeah yeah i know. 😢 its alot of work and admittedly, a little over my head atm. I have the specs for the cams and what not but thats alot of work i dont have time for right not. iiiiiffff a fellow solidworks buddyyyyyy wanted to, I would kindly give you a e-high five upon completion! > [@Cars for scrap prices](https://forums.speedlife.net/t/cars-for-scrap-prices/38657/3): > > damn thats nothing but impressive :hug thanks friend > [@what movie makes you guys cry](https://forums.speedlife.net/t/what-movie-makes-you-guys-cry/38649/35): > > If you can make one for 500$ ill pay you cash tonight, buy you a steak and a 36 pack of whatever beer you like. NattyIce! YESS ---
**Author:** ![Mafdark](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/mafdark/32/6322_2.png) [@Mafdark](https://forums.speedlife.net/u/Mafdark)\ **Post date:** [January 11, 2011, 1:59pm UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/19 "2011-01-11T13:59:10Z")
> [@Free range rover mods FTW.](https://forums.speedlife.net/t/free-range-rover-mods-ftw/38655/21): > > BALLS, I knew you or Adam would bring that up! yeah yeah i know. 😢 its alot of work and admittedly, a little over my head atm. I have the specs for the cams and what not but thats alot of work i dont have time for right not. > > iiiiiffff a fellow solidworks buddyyyyyy wanted to, I would kindly give you a e-high five upon completion! not gonna lie, uber complicated. What you can do though, is compare the data you have collected with data from simulating individual ports open. It won’t give you the overlap, but would give you a bit more than you have now. ---
**Author:** ![KrazyKid](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/krazykid/32/6371_2.png) [@KrazyKid](https://forums.speedlife.net/u/KrazyKid)\ **Post date:** [January 11, 2011, 2:00pm UTC](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373/20 "2011-01-11T14:00:08Z")
now that I think about it. Is it really that hard? I mean if I have say 1 cycle = 1 minute (for arguments sake). if my firing order is 1,3,4,2. 1 When 1 is at TDC, 3 is at BDC, having finished its intake stroke. 4 is at TDC, having completed its exhaust stroke. 3 When 3 is at TDC, 4 is at BDC, having finished its intake stroke. 1 is at BDC of its combustion stroke. 4 When 4 is at TDC, 1 is at TDC exhaust, 3 is at BDC combustion, and 2 is at BDC intake. 2 When 2 is at TDC, 3 is at TDC exhaust, 4 is at BDC combustion, and 1 is at BDC intake, ready to start the cycle over. couldnt I just input that in and see what the cam overlap duration is and factor that into the mix? I am sure I am making this way easier in my head than it actually is on paper/excel. lol any refrences on how to gather this data? simple java applet would kick SO MUCH ASS, if it existed where I could just input the build specs and RPM and poof out comes all the data! [Next page](https://forums.speedlife.net/t/1-8t-intake-manifold-design-and-construction/256373.md?page=2)