oh no doubt DonR put alot of work into it. afterall he did design the Monster 007 manifold, which any serious 1.8t guy should know was the king of the hill for ages.
APRs manifold with 75mm RS4 TB is still a tough one to beat. arguably better than SEMs manifold.
i considered running the SEM with a 75mm when i had my car, only because DonR offered me an amazing deal, but as you know things happen and car projects end.
Bejan (boostinbejan) made an amazing manifold for a while. he did alot of flow testing with various plenums(he used to work for Dinan, so he had access to such machines) he called his “inlet dynamics” i havent heard much from him since i got out of the 1.8t world.
but we both know, anything will work better than the stock junk. have you decided on a throttle body configuration?? driver or passenger side?
do a Force Fed Engineering Outlaw style center inlet. :bowdown
More or less, yes. I’ve never done it myself, but I can contact some people I know who did this for FSAE to see if they have any tips on it. I’ll let you know what they say.
Yeah that would be awesome. I will try to do a little more research and adn thinking too. I mean all I need is to open and close 4 lids at specific times. reverse engineering that in excel. Even if its not dead nuts with the timing of the cams, it will be farther in the ball park than it is now.
All very good points. I remember seeing and talking a little with boostinbenjan. I looked as his ideas actually when I was doing the research.
as for the center inlet style. I did this one for Aaron a few days ago.
I’ve got to say I’m quite impressed with your “pickup” ability with the program sofar. I’ve been dealing professionally with SW for close to ten years now and you don’t see many people pick it up quick.
Mafdark definitely beat me to the punch on the flow dynamics with reversion, but you also must calculate the ACTUAL flow each runner will receive with open valves. Your runners in this current test will be running @ 100% capacity, which is not what they will be doing at max valve lift. That part of it can be factored easy via modeled restrictor using basic port flow information for your particular head. Calculating the flow for reversion takes ALOT of math and knowledge in fluid dynamics. I worked on that manifold under Yetti’s hood for a long time before I found what I wanted, and even then had to cut it back some just to make it fit within the parameters of the engine comparment. In the end I ended up having to modify shit and move half his accessories to the rear of the motor.
A couple things you should be doing for this though when testing that are quite simple in effect.
1)build a false head in the project with appropriate ports. Complicated enough to get on your own without a laser probe, or cutting a head apart to get exact port dimensionality. I may be buying a laser probe in the near future. Borrowing would certainly be an option for you
2)absolutely build the throttle body model and use that on the inlet. That can change the flow characteristics ten fold. One should also build ~25% of the inlet tube going to the throttle itself(either intake pipe or charge piping)
All in all man, job well done. I deal with files from professionals that are FAR worse than this, and they make pay!
Adam thank you very much for the inspireing words! Its an honor, really to hear such praise come from someone like yourself.
Actually I can probably build a head, with simple port shape and decent dimensions I would the ports arnt too crazy shapped, and I can get in there with a caliper a little bit and give it the old laser eyeball once over and give it a swing. But yeah about that laser probe!!!
the TB i can do, infact ill get on that in a little while.
If you can’t get the port exactly how it is in the head, don’t bother making it. Minute changes in the port shape can yeild drastic changes on Flow. If you’re going to attempt it, the only other way to do it beside a laser scan is to cut open a junk head on port centerline for the dimensionality. You won’t be able to properly measure roof and floor angles, tapers, etc and those make huge differences in how a port flows.
You should just figure out what one of your heads particular intake ports flows at the max lift your particular cam produces, then CAD a simple restrictor to flow the ports through, you could even alter the flow procedure by flowing just a single port at a time as well.
If you can’t get those specs and the head is off the car, bring it to the machine shop and I can put a dummy spring in one intake valve and flow it on the flow bench for you(you’d just need to know your lift profile/spec of the cam to give to me)
What head is this anyway? I may have a busted/cracked/warped core at the machine shop in cold storage. there’s somewhere between 1500-2000 heads in there. I know I have a couple pallets of 4g63 heads, stacked 4 deep :lol
In all reality though, what you are doing there will account for 75% of any gains you’d see regardless, so going too nuts isn’t necessary(and you WON"T hear that from me often). I went beyond overboard with yettis manifold to grab every last bit of power I could.
Since my wife is home and in alot of pain from getting 2 pins and a plate in her wrist today, and I have been up every 3 hours feeding her pain meds… so i made this.
RGR that. I hear you. The head is an AEB 1.8T. The one I have is opened up quite a bit from stock.
I might have to take you up on the flow bench actually for the head. would be nice to know what it does over stock from the porting. also I need 5 valves, valve lash checked becasue they are new when I got it from the guy. I have all the specs on the cams too, ill bring all that. I will call you in the AM, well, I see its 1:30am… I will call you later today! lol
and if you dont mind, I promis I wont sell your design, could you send me yettis solidworks file so I can gawk over it? :ninja
Well I calculated the internal volume of the plenum. I hear you want it to be about the same as the displacement of the motor?
total for entire intake manifold runners included: 273.202258 in^3
total for AEB runners only: 62.7193 in^3
that says the plenum is 211.2 in^3 or 3.46L! either i bore and stroke the shit out of the 1.8T or I need a smaller plenum.
Is it that bad to have a larger plenum than displacement? I also head 1.5X the displacement is recommended. Annnd I also hear that a larger plenum might slow down initial spool, but act like a capacitor to hold boost/volume more on tap when its needed.
Very much so…depending on how fast you can fill the intake mani with new air will be the problem, turn the boost to 40 P.S.I basically. The bigger the plenum the steeper the drop in tourque, and it’s a motorcycle motor, you will never make huge power from it. I have 3 of these motors, each one makes decent power in three different trims.
What is this going to be used for? a class built drag car? Or roadcourse car? Cuz more than 250 wheel in a FWD car on track is useless and you’ll get smoked off corners all the time. Less over all power, good tourque and all the grip you can get. If it’s a drag car then you should probably just put an LS6 in it and make it RWD.
Been busy, car ran great the last part of the year so was on track the last part of summer…went back to work at my old dealer in latham…I-racing…call of duty…ya know. LOL.
I would think about getting the block machined for o-rings and run like 40 p.s.i. of boost, to make up for the tinyness of the 1.8T. Over boring will only make the engine pissed, displacement increases seem to hurt the rev happiness of this engine. Stick with standard bore and lighten the valvetrain as much as possible. Titanium retainers and springs, I’m sure you can get them custom made. The +valves are they iconel?
