Cool intake manifold project pictures...

[reuben_johnston]

Guys,

Check out the pics with the new extrusion piece.





rj

[cf_z]

wow.. i just cought this thread.

everything looks sweet!

[the3wang]

looks sweet man

[Nealio]

It is looking quite promising. Did you get the manifold volume you wanted?

[KING6]

I cant see how its going to be better then stock, gutted stock, a ZE or a gutted ZE. I cant even see how it would look better if anything...
good luck

[cf_z]

Originally Posted by KING6

I cant see how its going to be better then stock, gutted stock, a ZE or a gutted ZE. I cant even see how it would look better if anything...
good luck

your allways so positive about everything

[reuben_johnston]

Originally Posted by KING6

I cant see how its going to be better then stock, gutted stock, a ZE or a gutted ZE. I cant even see how it would look better if anything...
good luck

Shorter path from throttle body=better flow under boost. Less restriction=better flow.

I'm not going for appearance with my car, performance only.

This version won't have as much plenum volume as the other shape, but I believe it will not matter for V6 application. We will see when we dyno.

rj

[unorthodoxcreat]

Just found this thread today. Very cool looking project. I love seeing knew things like this. Maybe you know this but in case you dont-My word to the wise is get those runners as clean as possible inside and out. Dirty aluminum does not weld nice. Aluminum thats been soaking up dirt and oil for 10 years sucks to weld. Look forward to seeing your results.



Hey you're not even an hour away from me.

[KING6]

Direct from Maximum boost

Turbo applications will generally find best results with long runners, wich provide a broad, flat torque curve at low speeds, while the turbo keeps the top end strong

The intake plenum should be several times larger then the cylinders displacement

If you take a look at mici's old setup and new setup, you will see he went with a different setup to get more low end power..
also that czt manifold, Goldmember, CZT Boost, 342whp, 16psi, on mustang dyno. Some guy dyno'd on that thing and didnt get to crazy of numbers, also there plenum is much larger and there using velocity stacks inside of it. They didnt post a dyno chart or even the torque, they just claimed they made 40hp more.

[reuben_johnston]

I'm not going to start an argument over this. I have read both Supercharged and Maximum Boost cover to cover more than once. I also took quite a bit of physics classes in college.

My thoughts on this initial version are to have at least enough plenum volume for half the displacement. The main plenum section size (where the runners attach) will be slightly larger surface area than the runner surface area. There will also be a larger plenum section where the throttle body 4x4" opening reduces down to the main plenum section size. The initial plenum volume will be more than half the engine displacement (Maximum boost quotes 50-70% displacement volume for plenum volume on page 79). The throttle body I am using should not be a restriction, as it is 75mm.

Regarding runner lengths, there can only be as much air in a cylinder that will flow through its runner. Corky highlights symmetry in the design of the runner <-> plenum intersection, to maximize flow. Unfortunately, this design isn't that symmetrical. At WOT under boost, shortest path with best flow is the goal. Again, this design is not for NA application.

Sure, if I had lots of money to spend and could afford to manufacture a cast manifold setup, the design would be drastically different (that's a no brainer). Our biggest challenge in trying to maximize the plenum shape is the manifold bolt locations. However, the cost for prototyping a cast manifold is at least 10000. I do like the design of the mx3 engine King provided a link to. I would like to point out that that version involves significantly more fabrication.

Anyway, bottom line is, this version will be quick to fab up and we can get it on a dyno to test. Hopefully, there is somebody within driving distance to the Baltimore area who already has a boosted setup working well. We can try it on a dyno and compare to the stock manifold. It will be some time before my mx6 is drivable, as I am also designing my own ECU system (because in my opinion, current ecu designs are lacking). If that is the case, it will just be longer before I post numbers.

Cheers,

Reuben

[Radar]

Originally Posted by KING6

Direct from Maximum boost





If you take a look at mici's old setup and new setup, you will see he went with a different setup to get more low end power..
also that czt manifold, Goldmember, CZT Boost, 342whp, 16psi, on mustang dyno. Some guy dyno'd on that thing and didnt get to crazy of numbers, also there plenum is much larger and there using velocity stacks inside of it. They didnt post a dyno chart or even the torque, they just claimed they made 40hp more.

Umm...misinformation

In the context of Mr. Bell, it would be "ideal" to have that larger plenum, but there are other factors as well that Reuben has mentioned. For n/a purproses, I would say that manifold would require the engine to rev to some serious rpm to take advantage of the increased air flow abilities..a la..PRM.

Rob of CZT dyno'd his manifold n/a and picked up some ~20hp, but that was at 9000rpm with CAMS.

I was there, tuning THAT car. It was a 40hp gain at 14psi over the previously GUTTED millenia manifold on the same exact dyno and same turbo setup. I would call that a significant gain from a bolt on mod.

For those looking to go fast, who the hell cares about low end tq for a race car? How often are you drag racing below 4k? Yes, the manifold shifted his power curve to the right, so far in fact he now is building a head to rev to 8k to take further advantage of it.

[KING6]

Sorry, i plagiarised both quotes. Fig 6.9, pg 77 & 78.
It doesnt say Ideal, nor does it go into much detail

Also, he gained some power at rpms that will destroy a stock valve train.
But did he loose any power through the lower rpms?.

Id like to see a before/after dyno graph

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btw, are you still able to remove the injectors from the manifold once its welded together?...

[DrBrown]

First thing you need to do with the runners before it gets welded is round the inlets inside the runner so its more like a velocity stack instead of just a squared off hole leading to the head.

I dont buy into this volume argument for the intake. Certainly bigger is better to an extent but dont forget here the intake manifold is pressurized. Which means every square inch of the intake from the compressor to the cylinder head is pressurized equally. So in theory every bit of air intake that is available will be shoved into that cylinders intake valve for hte brief moment it opens. I do agree that the setup thats in the pictures with the square tubing is too small to make top end power. But I still believe it would be a 12-15whp increase at the least over a ZE manifold just because the single chamber design.

I plan to make a nice welded intake too but I dont like how tight te injectors fit in there. The best way to do this would be remove the stock injector rails entirely and mount the injectors on the outsite of the runners and point them more towards the intake valves so its a straight shot instead of how inefficient the stock setup is. Just some constructive criticism for you to mull over going forward. Good luck with the project, looks great so far!

[reuben_johnston]

Originally Posted by KING6

btw, are you still able to remove the injectors from the manifold once its welded together?...

good point, i need to confirm that one. i believe they can be removed from the bottom side (if the manifold removed), but will confirm.

----

test fitted the plenum extrusion yesterday and it is slightly too tall (about a .5" at one point) and rubs bracing on one point. i was smart and also ordered a 2x2" channel extrusion. this will be easier to cut the holes for the runners as well, here is the pic below in the car.



rj

[fredio54]

one reason why you want a significant volume in your plenum is because as each cylinder draws, the airflow through the throttle cannot keep up with the demand, thus pressure drops, and the cylinder sees less boost as the induction cycle moves towards its end.

that 2x2 box is sooooo small.

if i were you, i would consider chopping the runners off a lot shorter and putting a large flat box over all of them rather than between them like that.

if you cant access the bolts like that you could tig in bolt access tubes and or use long bolts to do it from the top all the way through.

as bad as the low volume is the sharp edges... how are you going to properly radius the ends of those runners? ideally you want a bell mouth in there, but even a slight flare would be better than a sharp square edge. even just having the runners protrude into the box a bit will be better than a T joint.

also with such a terribly small volume, its highly unlikely that the far end runners will see the same flow as the near end ones. that is one area where you must be very very careful if you dont want to run into one cylinder being a bunch leaner than some other one. this is a real problem. and a serious one too.

heres a thread on how i built mine for my 2.0, its i would say over 3.0 in volume, and has nice radiused entries to the runners. its not ideal though, as proper bell mouths with turned back edges would have been best, but its pretty damn good. not the distance from the number 4 runner to the back wall, and the tapered nature of it to ensure even air distribution.

The 2 bagel intake manifold.

i appreciate you have limited space, but it would be a real shame to put in a LOT of work and end up with something worse.

i just had another thought.

if you put flanges on the tops of the runners and build it in four parts, a bottom section in a U shape, a top cover plate, and two stub port adapters, you could install them first, put gaskets or rtv, bolt down the U shaped piece, and then clean up the insides if you use rtv, then install the top plate.

considering the amount of power you can make on a stock setup, what power are you aiming for here? whatever your goals, you need to be very careful indeed to get this right or it wont be pretty in the end.

fred.