tooter's manifold adventure...

[mr_miles]

I love this thread. I wish I was closer so that i could help :/

[tooter]

That would be lots of fun...
Well, at least I can keep you posted every step of the way. I just ordered a part for the manifold plenum, and will post pics when it arrives. It's something which has absolutely no relation to engines, and I'm adapting it to an unintended purpose.

As far as I can tell from searching the web for everything about intake manifold design I could find... no one has built the design I'm going to try. There may be a reason. Because it doesn't work! But I'm going to find that out for myself. I'm building one manifold designated for testing only. And the good part is that if the experimental designs don't show any gains on the dyno, I can always simply cut them off of the runners and try something else.

[Flipper_1938]

If you are going to try a really large diameter plenum...large diameter equals low velocity.

[tooter]

Originally Posted by Flipper_1938

If you are going to try a really large diameter plenum...large diameter equals low velocity.

No, I won't be doing that. First off, there's no room for a larger plenum with this particular manifold design while keeping the air filter under the hood. And second I don't want to go larger. Instead, I'm going to a smaller plenum. The existing one is already almost non existent with that big thick intake tube occupying so much volume...


...and yet that design works great! I believe it is because of the unique configuration with all the runner entrances pointing directly at the bore of the throttle body...



That internal intake tube terminates only a couple of inches in front ot the runner's entrances. So there is very little plenum volume left over.

When I get the part, I'll be able to measure exactly how much smaller if at all by filling both plenums with water. What will be radically different is the profile of the new plenum. I literally dreamed up this crazy idea...

[Bluevitz-rs]

Cool Tooter! Are you reworking the manifold with your own plenum and TB mount?

[tooter]

Originally Posted by Bluevitz-rs

Cool Tooter! Are you reworking the manifold with your own plenum and TB mount?

Yes.

I have a totally "outside the box" idea and am going to build up a tooter and dyno it just to see how the concept works.

[tooter]

The new plenum came today, and it has nothing to do with intake manifolds. It's a structural architectural ornament. This is the basic layout of the experimental tooter...













I filled up both plenums with water to test the volume, and was totally suprised to discover that they both hold exactly 26 ounces! I'm always looking for omens and this is a really good one...



The old plenum appears to be a lot larger because there is so much material inside it which by displacement decreases the volume.

[cali yaris]

Phallic!

[tooter]

To you, everything is phallic.

[CrankyOldMan]

Hmm, what about the 6" tube remnant?

[tooter]

It's right here...



I think I'll try it without this time since the two plenum volumes already match. I can always cut off the hemisphere and add a ring later. And while the plenum is off I can clean up and smooth out the runner entrances.

[CrankyOldMan]

Originally Posted by tooter

And while the plenum is off I can clean up and smooth out the runner entrances.

Yikes, those are some gnarly welds for a flow surface.

Thinking back to my own can-shaped design, the flow analysis showed that there was pretty much no air movement in the shoulder area of the TB side.

[tooter]

Well, remember that it was just a mass produced Corolla manifold and not a high performance racing component. The welds are actually well controlled, but I do think I can improve the runner ports with the trusty old Dremel... something that no manufacturer would take the time to do because there's no return on investment.

[malibuguy]

they welded them like that for easy access & it smooths out the lip that would be there if they were externally welded

[xnamerxx]

^ that and it would be next to impossible to weld them externally.

[JustDidIt]

Interesting... whats the next step??

[malibuguy]

Originally Posted by JustDidIt

Interesting... whats the next step??

procharger

[tooter]

Originally Posted by JustDidIt

Interesting... whats the next step??

I don't exactly know just yet... I'm thinking about it while finishing another regular tooter.

For sure, I'll need to have a plain throttle body base plate made and figure out a way to attach it securely as the aluminium hemisphere shell is pretty thin. I was thinking of a short bellmouth on the inside like this extending a couple of inches into the center of the hemisphere directly aligned with the axis of the 4 runners so the flow is a straight line.



The throttle plate will use the same CNC information for the outer surface minus all of the adaption machining. It'll be one inch thick to raise the throttle body enough for the chip to clear the hemisphere.



Here a flow simulation for a bell mouth...

http://www.youtube.com/watch?v=jFwo_3IxZyo

If it works one way... it'll also work the other.