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I am starting this thread for those of you out there that have an interest in ITB's. Some of you have done your own projects and there are others out there that might be interested in starting there own project. Well, we will give it a shot and see what happens. Enjoy.

Redline/Weber Throttle Bodies
http://www.redlineweber.com/html/throttle_bodies/Throttle%20bodies_side_mount.htm
http://www.redlineweber.com/html/throttle_bodies/Throttle%20bodies_dcoe.htm
http://www.redlineweber.com/html/throttle_bodies/Throttle%20bodies_idf.htm
http://www.d-series.org/forums/showpost.php?p=158074&postcount=64

ITB info from threads:
crazy idea need some input on ITB
sloazzcivic99
http://www.d-series.org/forums/showthread.php?t=16326
ITBS management ?
Belette
http://www.d-series.org/forums/showthread.php?t=15890

http://www.honda-tech.com/zerothread?id=765133
http://www.honda-tech.com/zerothread?id=473099
http://www.honda-tech.com/zerothread?id=360601
http://www.homemadeturbo.com/forum/index.php?board=1;action=display;threadid=13687
http://www.homemadeturbo.com/forum/index.php?board=1;action=display;threadid=14730
http://www.honda-tech.com/zerothread?id=303926
http://www.honda-tech.com/zerothread?id=260670

slebidia's DIY ITB pics
http://www.slebidia.addr.com/airbox.htm
http://www.slebidia.addr.com/images/itb/
http://www.slebidia.addr.com/images/intakes/

Moose's ITB Project
http://www.redpepperracing.com/gallery/CBR-929-ITB-project

jdmlife ITB's
http://www.westkyimports.com/forums...98&page=1&pp=10

http://www.abdgraphics.com/iansite/ianthrottlebody2.htm

Thanks to oldschoolteg and slebidia for help with the links


ITB Video links
http://www.soniderosusa.com/media/bseries.wmv
http://www.soniderosusa.com/media/bseries2.wmv
w/ a link to this setup:
http://www.honda-tech.com/zerothread?id=1079706
 

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i got them in the mail on friday. Mine are smaller than what most people use. i have the 600 itbs which are 38mm. the newer 954cbr uses 42mm itbs. The 600f4i still uses 4 nozles per injector but i have no idea how much they flow :? . Hope fully my small itb equals more streetabilty and it will be easier to tune. BUT, my motor is still disassembled so i am a long way off :!:
 
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we'll see how streetable my ITB's are, give me about one month. they'll be done then and the weather will hopefully be a lil' better here in michigan
 

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Here is my project ... it is about halfway completed. The ITB's will evetually go onto my current motor which is a built 12:1 D16Z6 motor, in my 93 Civic Si

About 3-4 months ago I picked up a set of Honda CBR 929 ITB's off Ebay. I choose the Honda ITB's over Gxer or similar ITB's since the Sensors on the CBR929 ITBs are plug and play with the my engine harness (TPS, Injectors, IAT). At the Same time I picked a set of airhorns from an old-school VW.



Once I got the ITB's in I compared the bore spacing of the ITB'd to a Stock D16Z6 Intake Manifold ... and it is very close.



Once I determined that a OE Z6 IM would work I took the ITB's and the Z6 IM to a local Fabricator .... Graeme at Canadian Cylinder Head to fabricate an manifold to adapt the ITB's to a D16Z6 head. Because the CBR ITB's are attached to the CBR head with rubber couplers, there is 2" flanges already on ITB's so the D16Z6 IM only needs some 2" alunimum flanges shaped and welded into place and some 2" silicon couplers to join the ITB's to the Manifold. He cut, shaped, welded, and ground the 2" alunimum tubing to match the oval intake ports and to match round exit ports where the ITB;s mount. This week I got the new custom adaptor back from Graeme, it is a work of art.





Because the VW airhorns do not have the right mounting flanges to attach them to the CBR I need to fabricate some new flanges. So I took the Stock CBR Airbox and cut the old flanges out of the box



and them I trimed the flanges down



and then I inserted the airhorns into the flanges ... ultimately I will silicone them into the flange



Once I figured out the air-horn mounting ....I then mocked up the entire ITB setup on a spare head to see if there is any issues

Here is a 3/4 view



And a side view



So now I am in the process of figuring out the vacuum and coolant routing, and what I am going to do with the Injectors. I have three choices, Highflow CBR inj from RC, Modified Prelude injectors in the stock CBR location, or Prelude injectors in the Z6 stock location.

Once that is done ... the tunning becomes the issue. I think i may have resolved the low vacuum issue and how it impacts tunning and the A/F maps. A local tuner is building a custom re-curved Map sensor (he builds Turbo Maps) for low vacuum situations. This hopefully will allow me to tune properly using Hondata, with out having to resort to TPS only tunning below 5k. But this is a couple of months away ...

FYI Here is a link to a bunch of pictures of the ITB project

http://www.redpepperracing.com/gallery/CBR-929-ITB-project


Cheers

Moose
 

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Discussion Starter #14
redzcstandardhatch
ITB setup pics/movies
http://dserieshonda.com/modules.php?name=Forums&file=viewtopic&t=182

http://d-series.org/viewtopic.php?p=40929
redzcstandardhatch's itb project.

first off, let me say that this is copied from a post i did on honda-tech, so you might have seen it.....i'm posting it because some people have asked for pics and figured you'd all enjoy them because its a d-series (kinda, it on the bastard dohc zc.....i love those motors)

"ok, i finally finished my homemade ITB setup for my worked over dohc zc. the engine has a mildly built/milled head and exospeed stage 2 cams. the ITB's are cbr 954 units. the velocity stacks are OLD school weber billet stainless pieces, i torched them a bit to get a differnt effect. all the aluminum plates show are one-off cnc machined by my brother on his cnc machine (check out his website for his products, http://www.nightmarechassis.com ). thanks for takin a look, i'll post a movie soon when i get it running (currently missing the header, i'm re-designing it, should be done welding it up by next week). have a good day everybody"

http://www.staticmethod.net/itb/index.html

http://www.ef-honda.com/main/viewtopic.php?t=1846
 
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redzcstandardhatch said:
nice work man. very cool manifold.
speaking of manifolds and spacing, those with CBR throttle bodies, have you noticed that they are in fact two twin bodies bolted together. my 929RR came in today and i took them partially apart. one could use spacers or washers to move the two halves more apart, making the fitting almost OEM. i shall try that as i continue taking it apart. (gotta love 2001 parts, bolts and nuts break loose easily).

on the unrelated note, what is that idle control looking valve next to the idle screw?
Stan
 

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Ya, I did notice that they were a pair of TB'S ... but I wanted to retain the OE configuration of Linkages, etc ... I was fabricationg a manifold ... to make a manifold that flared out slightly to mate with the CBR TB's was not an issue ... In my eyes it was the least evil of the two alternatives

The Idle valve thingy beside the idle adjuster is a "Wax" cold idle valve.

Cheers

Moose
 
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ok, i am interested in this project. It all looks very well done. I have a few questions.

How are you gonna control idle with this setup?
Where would the IACV go?
Where would you mount the map sensor?

Also, i have a recomendation about the injectors. Now, remember i have never attempted to make ITBs before so this is just a recomendation.
I have ported and polished alot of heads before, and from experience i found that if you leave the intake ports rough, you make more power. The reason behind this is because the roughness couses turbelance and does not allow the fuel to stick to the port. Now where i am going with this is that if you position the injectors on the throttle bodies, the fuel will enter the port pretty far from the combustion chamber, giving it more time to stick to the walls. This in turn will lead to less power. Even if the fuel end up pooling up and making it to the chamber, it will not be good because it combusts best as a mist .
 

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AudioMan ...

AudioMan said:
ok, i am interested in this project. It all looks very well done. I have a few questions.

How are you gonna control idle with this setup?
Where would the IACV go?
Where would you mount the map sensor?

Also, i have a recomendation about the injectors. Now, remember i have never attempted to make ITBs before so this is just a recomendation.
I have ported and polished alot of heads before, and from experience i found that if you leave the intake ports rough, you make more power. The reason behind this is because the roughness couses turbelance and does not allow the fuel to stick to the port. Now where i am going with this is that if you position the injectors on the throttle bodies, the fuel will enter the port pretty far from the combustion chamber, giving it more time to stick to the walls. This in turn will lead to less power. Even if the fuel end up pooling up and making it to the chamber, it will not be good because it combusts best as a mist .

Idle is controlled by the throttle linkages ... the idle adjuster (the shaft sticking up away from the camera) "pre-tensions" the linkage, cracking the throttle open just enough to idle.

Because there is no plenum ... there is no easy way to control idle by allowing more bleed air in (via the idle air motor) to raise idle under ECU control. As a result the IACV becomes redundant, it is left hooked up just to keep the ecu happy ...


Map sensor, You willl notice a bunch of vacuum lines runing from each of the TB's ... one from each TB is tee-ed together which then feeds the MAP and the Brake booster, two other vacuum lines from cyl 1&4 feed the FPR.

Injectors ... YUP I know about the finish required on heads ... I have done a couple myself. The Current head has a 60/80 grit finish on th intake side, to help keep the fuel in suspension. I will also put a 60/80 grit finish on the Manifold as well as gasket match the manifold to the head. The ITB's step down into the Manifold, and the manifold steps into the head.(bit of anti-reversion). The head also decreses in size from the ports to the valves pretty susbstantially (I did NOT hog out the ports after port-matching, just tapered them.)

All of these things SHOULD help keep the AF mixture swirling and off the walls.


Good point on the Injector placement ... but I think the Big problem with ITB's is that there is not much space (short small runners) to help the Fuel atomise and to mix well before it hits the combustion chamber. As a result IB manufacturers typically need to put the injectors as far up the runners as possible to help the fuel mix properly.

Also the the CBR-929 injectors use 4 orifices in the injector to spray the fuel in a more diffuse/fine spray to help atomisation. Sooo I think the wall finish is going to be vital to keep the mixture off the walls.



Cheers

Moose
 
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