Individual Throttle Bodies and Improved Airflow

[Boxersix]

Tony, aluminum may or may not suffice depending on the surface area of the box. Aluminum does have the ability to get a big harmonic in it and flex, you'd be using a minimum of a .120" sheet. Adding external ribs would assist.

However you've got a mill. Machine a billet cover for the thing with external ribs and it won't flex

Alternatively, you could make an aluminum box with a quasi-isotropic top plate of carbon fiber(VERY ridgid) that you bolt down with a seal

so many options

[Dessertrunner]

Thanks for the suggestion, I was wondering if using wood to mill up a female mould, a sort of combernation of both suggestions then use carbon fibre The biggest problem is that its a whole new skill I will have to learn. Adam was the carbon fibre hard to work with?

Okay so I have to build the cover plates for the rollers which have the bearings as well. Then I need to mill the roller to suit the port. Each roller has 2 bearings which have none contact seals (has seal but doesn't touch the centre). I was concerned that with 24 rollers would have to much drag.
A challange I have to face up to is that the clearance of the ram pipe at the front of the engine clearing the bonnet. During the week I will try to do the face plates need to keep going forward. Also need to sort out the linkage some how.
Here are a couple of recent images.




Have great day or night were every you are.


Tony

[Boxersix]

Composite layup is indeed another whole set of skills, but nothing that can't be learned. The downside is it requires a small host of various equipment to do properly(vacuum bagging so to say, or autoclaving). The layup is though the easy part, the knowing about how to make the part structurally sound with proper resin ratio and weave/core substructure is the tricky part if you're new to the field. Building a negative old to vacuum bag a positive chamber is the right thinking though.

Full contact roller bearings of this size don't induce too much drag. ZZ full shielded bearings(metal shield, non-contact) are just as good in this application if there is no intent of forced induction where they would certainly leak and required external shaft seals.

[oab_au]

I don't think you should get too high tech with the air box, as that is all it is, just an extension of the air delivery piping.
It doesn't have to withstand big pressure changes, as long as it has a big enough volume, just deliver clean air. Check the ones used on cylinder bikes, same thing.

Harvey.

[Dessertrunner]

Good point Harvey, I am getting a bit scared when you mention vacum box Adam. I am using ZZ bearing so thats good to here its the right ones.

How big in volume does the air box have to be, seem to remember seeing it somewere.
Tony

[oab_au]

Originally Posted by Dessertrunner

Good point Harvey, I am getting a bit scared when you mention vacum box Adam. I am using ZZ bearing so thats good to here its the right ones.

How big in volume does the air box have to be, seem to remember seeing it somewere.
Tony

It's not the same as a plenum, just big enough to represent the atmospheric conditions as if the trumpets were breathing from the open air.

Like an under half and a top half, sealed around the trumpets with some foam, connecting to the original air pipe and air cleaner.

Done in fiberglass?

Harvey.

[Dessertrunner]

Harvey I am going backwards with the intake as there is more room were the firewall is to fit the aircleaner etc. I like the idea of bottom and top half I had been thinking it would be a pain to feed each pipe through the side plate etc.
Some how I need to fit a MAF meter is the design.
Tony

[Dessertrunner]

Okay I have been looking into carbon fibre and I think that is the way to go. I now understand why you use a vacum pump and thats no big deal, already have a vacum pump for test equipment at the factory. Also I didn't mention but about 10 years back my company built 60 pickle tanks on a computer control filment winder, these suckers were 10 ft high and 14 ft diameter all this spinning in the air. I figure I can do the job. Will do it the way Harvey suggested.
Adam should I make a alumiun flange were the top and bottom meet and mould it into the carbon fibre?
Tony

[michael]

Did you consider hacking up an EZ30r manifold?

[Dessertrunner]

What are they made from? Also were is the airfilter?

[Dessertrunner]

Guys what do you think about using 2 of these airboxs, any negitives?

tony

[Boxersix]

aluminum must be separated from any carbon in the matrix by a laminate barrier(fiberglass or kevlar) as the carbon will cause electrolosis of the aluminum and initiate heavy corrosion. but yes you can bond an aluminum CNC'ed flange into carbon composite, we do it all the time

picture you posted looks like one of the BMC style carbon air filter canisters(or similar knockoff)

[Dessertrunner]

Adam do you think this type would work?

[oab_au]

Originally Posted by Dessertrunner

Guys what do you think about using 2 of these airbags, any negitives?

tony

Tony, two separate air-boxes would still have the sides divided. The three cylinders would develop an oscillating surge, like the Inertia system, that would interfere with the air flow. With one box the cylinder inlet air demands overlap, so the surge would not happen.

The main point would be to ensure that the area of the box where the trumpets open into it, needs to be twice the diameter of the inlet pipe to allow sufficient expansion of the wave.

Harvey.

[Boxersix]

^ what Harvey said Using two of those "chambers' would essentially put you back as a stock plenum minus the IRIS.

As Harvey stated, airbox volume in an ITB isn't as complicated of a calculation as a plenum is in a normal intake manifold. In this application and space constraints, you almost can't go too big, so use as much volume as you can under the hood.