I am about to start some R&D work on AFFORDABLE ( trying to hit sub $2,000 range) billet aluminum ITB's. What are some things you guys would like to see in a set of ITB's? What sizes would be a good all round size? I was thinking starting off with 48mm bore and offering custom sizes for an extra charge.

I plan on making a plenum available for my ITB setups as well as coming with a set of removable velocity stacks.

Which head setup would you think will be most popular? I plan on making the first set fit L92/LS3 heads. Should I consider other head setups as well?

 

cathedral port

 

The ITB's will be a "base plate" design allowing different intake adapter wedges to be made. Cathedral port will likely be one plate design.

To do a cathedral port setup, I would need a set of donor heads to do a mock fit on since all I have is a set of new L92 heads on a LS2 block.

 

One MUST is that it fit under the cowl of a f-body with little/no modifications to the car. That would be a huge thing. I think the Harrop is the only one that thats the case with and its VERY expensive, and I've heard its alot of **** to get it right. Another plus would be to keep a direct port setup in mind for those of us who would run nitrous on it. I can see it being hard to plumb up a direct port setup depending on the design.

 

I'd be intrested in helping! (CADD major here)

 

The first thing I want to see is one on my car with 55mm bores...

 

It would be wonderful to have some CADD work for the adapter plates. I was going to hand program the shape and contour of the ports to adapt to a round hole. I would really be interested in doing something with you. I was going to try and do it with my MasterCam X2 and some subtle changes at the CNC mill.

That would not really be a problem, I think. All I would have to do is get a couple measurements for space constraints. I am pretty sure that could be arranged.

Direct port is rather simple, I could even plumb it to a -AN fitting for easy hookup.......for an extra charge of coarse. That is nothing but notching for another hole and bracket and getting the depth right.

Also, for diameters, I think I am only going to go with two sizes. 48mm and 55mm. Any other sizes would have to be custom.

I am also looking into a way to have some fittings so that I can make a pressure proof intake so they can be used for boost. The design I have in mind will be short in stature and spacers can be added to increase runner length for those interested in long tube ITB's.

 

For my final project i will be doing a ITB set up on Autodesk Inventor. Think it would be cool bases off my PI LS7 cylinder heads.

Adapter plates...?

 

If you build them like this (link below)...with different length stacks that can be quick changed....you will sell them like hot cakes for under $2,000. Make sure it also has a variable throttle cable cam gear too.

These people didn't reply when I tried last year a few times.
http://www.extrudabody.biz/servlet/t...evy-LS1/Detail

Here's the different length stacks they have:
http://www.extrudabody.biz/servlet/t...ies/Categories

.

 

I have a set of 853's that are yours for shipping cost

 

The design I am making will be a VERY sleek looking unit. The base is a wedge that bolts directly to the head and adapts the port shape to the matching diameter of the ITB. There will be a corresponding top plate that will bolt on. The ITB's will bolt to the top plate from underneath that way the look is sleek and void of any brackets or flanges. Then the top of the ITB's will have four holes allowing for a variety of mounting options. You can bolt the extension adapter to the top of the ITB or to the bottom, your choice.

The throttle cable cam will be an very simple setup and will come with a couple different length rods to allow for an almost infinite amount of adjustment. The pre-fitted adjustment settings will be marked for a baseline though.

Everything will be polished and maybe even hard anodized depending on pricing. Also, custom anything can be done to them. I have a full function machine shop at my access to develop these.

I am really looking into making a boost ready setup, especially since I have a customer already lined up for one if I can do it.

 

If you can do this for the price you say, I'll be getting one as well if it can show a improvement in performance (shouldn't be a problem I would think?). What kind of TBs are you planning on using? Also, how do you plan on integrating the TPS sensor?

 

Any sort of individual throttle body will make a substantial performance increase, providing the port sizes are matched properly.

The throttle bodies I plan on using will be my own design all made in house (MAYBE with the exception of the throttle shafts). The throttle plates will be brass plates, the rest will be stainless and aluminum. The design I have drafted up so far is going to be a knockout in the looks department as well as TONS of room for bore size options (Maybe up to 59-60mm!).

The TPS will be VERY simple. The throttle cam shaft will attach directly to a housing and bracket specifically machined to accept a standard GM TPS. (5.0v reference)

Trust me guys, when I am done, you will look at these as a head slapper. You be all like, "why didn't I think of that".

 

Air filters, air boxes, ability to suck the air from outside the car???

Christian

 

The ability to suck air from outside will be up to the car owner. I can make ram pans that can mate up to a hood but that is about it. The air filters will be of the high revving motorcycle throttle body configuration. One per TB.

I plan on making a boost sustainable air box to connect to the ITB's for those that wish to boost their setups. I will also likely make spacers with additional injector holes for those that need it. Obviously that will be a by the order part.

Everything will be sealed with o-rings that are standard size. That way the gaskets are cheap and readily available.

So far the design is coming along pretty good, all I need now is to start getting measurements like injector hole diameters and to get dimensions off of the L92/LS3 style ports and from the cathedral ports. Once I do that it is just a matter of time before the first set will be made.

 

Beard, I would LOVE to test one of these for the cathedral port heads. I have a few sets laying around I could part with for just shipping if we could work something out. My LS6 intake is REALLY holding me back I think...This thing should do the trick.

 

First thing I would do, is go put my hands on a few different sets of ITBs already out there. That way you can see what others are doing, and either their respective shortcomings, or what you like about them. One of the best things you can do when trying to re-engineer something, is to get an idea of how others are doing it. That way you can see what you do and don't like about an existing product or part.

There is alot more to consider than a single cylinder setup as far as designing ITBs. One thing is total packaging. Size, layout, etc. Next is indivudual cylinder tunability. This is a problem with a common throttle shaft, and a common throttle shaft is one of the features that greatly reduces cost of manufacturing. Then there's the problem of a common plenum. Unless you're casting the lower manifold, something will need to be done about a common plenum, if you intend to run an IAC, or MAP sensor, etc.

Good luck in your endeavor. I think you will find it more than "challenging" to try and manufacture these for the price quoted.

 

Edcmat makes a good point. I was thinking about it last night, and you'll also have to figure something out as far as vacuum goes. I'm pretty sure most of us would like to keep out power brakes for sure.

 

DAMN, what a buzz kill...

 

I have both a set of Toda Racing ITB's and a set of TWM ITB's for a couple different Honda engines. I have made about 10 or so sets of ITB's out of Honda 954RR throttle bodies with great sucess.

I will flow all ITB's for a symmetrical idle opening to a metered amount of air required to keep the engines running. It will be adjustable by the customer but will be wax sealed so that people don't tamper with it unless they have the equipment to set them.

As for the vacuum manifold, done and done. I already have one made up and I even have a mounting bracket designed. There will be four 1/8" NPT holes to install small barbed nipples and a larger 1/4" NPT hole for the brake booster hose. I am also thinking of making a mounting surface and using a Denso style MAP sensor mounting point. That way I can just include the MAP sensor and a pigtail harness to splice in to the vehicle harness.

The part that actually connects between the cylinder head and throttle bodies will be machined from a solid billet. The intake plenum chamber that will attach to the ITB's is an optional piece and will cost more. Some goes with a ram pan for those that want to use a ram air hood. Also, for those that want to use this in a boost application, the plenum and parts required to make it happen will cost a decent bit since everything will be bolt together requiring the plenum be made in two halves. This has to be done so there will not be any areas for leaks to form.

The ITB setup I am trying to get into the $2k (may be a little more, but hopefully not much) or so price range will consist of the following:

8 ITB's (two sets of 4) completely assembled
2 ITB mounting plates L & R
2 adapters to go between the cylinder head and the mounting plate. These can be changed to fit to just about any engine
1 vacuum manifold and mount bracket
a roll of O-ring
all vacuum hose required
TPS already set to proper specification will be mounted to throttle cam assembly.


All of this will be made in the USA and I WILL NOT outsource any of it. I refuse to send money out of the country if I don't have to.