F22a ITB's (pics)

[F22Turbo702]

Ok, so I've been thinking about including ITB's in my turbo build...well, enough thinking, the time has come...I'm using my F22a1/a4 intake manifold and CBR 929 ITB's. The manifold has been cut behind the fuel rail mounting studs, but I need to do some clean-up work...I can't cut a straight line to save my life so, here's the pics of progress so far.







I'm going to run these N/A on my automatic until the motor build and 5-speed swap are complete, then I am going to build a plenum box around them that the intercooler piping will feed into.

I know that these will require extensive tuning however, due to my slushbox trans I won't be able to run Hondata until I finish the 5spd swap. I have found that quite a few people have had good results using the S-AFC2 to work out A/F problems that result from the MAP sensor readings being messed up from the lack of a plenum.

Anywayz, let me know what you guys think. The CBR929 itb's will be here sometime next week. More pics to come, I'll be getting the runner lengths evened out tomorrow when I go into work, and I'll finish removing the EGR port and retapping the coolant opening to use a threaded fitting.

-Kyle

[HondaB18]

ah, nothing like a turbo with itb. last i read about them was about the rb and the sr motors

any reason why you chosed the CBR929 itb instead of others?

i would be really careful on the s-afc and advise you to go invest in a standalone system

[F22Turbo702]

I chose the CBR929's because the TPS is plug'n'play and there are no secondary butterfly holes to plug. Also, the 929 inlets are large than the 600's.

As far as the S-AFC, like I said before, quite a few people have had good results with it, and due to my auto trans, I can't run a standalone until I do the 5spd swap...plus I happen to have an S-AFC sitting in my closet collecting dust. But it is only temporary, and only to lean the car out at idle and get a drivable A/F ratio.

-Kyle

Edit: I'll only be running the S-AFC while N/A, not boosted, boost will be tuned with the Hondata S300, but that is a ways off at this stage in the build.

[arthaccord]

pritty sweet i really want to do sumin like this so keep is up dated

[K2e2vin]

You shoulda went 954's, theyre bigger(but still not as big as Busa ones). Anyway, good luck on your build.

[ehulst]

nice dude, its a start, i'm running GSX-R 1000 ITBs 45mm....use crome for tuning, uber sucks....

[NAiL05]

You can run a chipped po6 on the auto with uber 1.66 but i dunno if uber supports the software to run ITB.

[F22Turbo702]

Well, right now I'm on an extremely tight budget and I don't want to hassle with a chipped ECU, I already have an S-AFC and I know how to use it. Plus, the S-AFC uses thottle position as a key factor in tuning which helps with the vacuum issues associated with itb's. Thanks for your comments, I'm going to work to finish cleaning up the manifold, I'll post more pics once I get back.

-Kyle

[K2e2vin]

nice dude, its a start, i'm running GSX-R 1000 ITBs 45mm....use crome for tuning, uber sucks....

those are 42mm, I had them on my JDM D15B VTEC(I scrapped the old manifold and am building a better one). Busa's are 46mm.

The S-AFC well work OK, but something like Hondata will yeild more power. A guy on D-series.org(and Honda Tuning magazine; his name is Bambooseven or something like that on d-series), installed GSXR1000 ITBs on a D16Z6; with just a V-AFC they got around ~126whp, but with a program(I think is was Hondata), they got 140whp. DOG had posted up the article from that issue but its somewhere in the archives now.

Btw, P28/P30, use Crome
P72/P73, use Uberdata(although, I dont think its been updated much).

[F22Turbo702]

In regards to using GSXR itb's...bigger is not always better, and I believe the 929's will yield good results.

And, as previously mentioned, the S-AFC is tmeporary and Hondata will be used once I do the 5-spd swap in the next 2-3 months.

-Kyle

[K2e2vin]

For a turbo build, a bigger diameter TB will be better because it'll allow a higher volume of air to flow to the head. The 929s should do fine though, but I believe theres more potential in something a little bigger(hogging out the runners would help too).

[F22Turbo702]

I don't want the throttle opening to be too large because I will lose velocity, I can have all the air in the world, but if it's not moving fast enough and atomizing the fuel than there is no point.

Plus we have to keep in mind that I am going from a single 58mm opening to 4 42mm openings....that's a huge increase.

-Kyle

[K2e2vin]

I don't want the throttle opening to be too large because I will lose velocity, I can have all the air in the world, but if it's not moving fast enough and atomizing the fuel than there is no point.

Thats the thing though, in boosted applications, having it small will choke it. You want a high velocity in an naturally aspirated application(this high velocity actually helps scavenging; this doesnt really exist in boosted applications because the turbine is constantly pushing the air in). In a EFI, the injector nozzles help do the atomization.

929s are 40mm IIRC.

BTW I will be running 52mm throttles bushed to 48mm, in an naturally aspirated F20B or H22A(whichever I come across first; bracket for the ITBs are still on the drawing board until I can figure out how to set up a decent throttle linkage). In comparison to B and K series, this seems to be a decent size given the rpm range and displacement of the motor.

[v4lu3s]

i have always had to switch 2 wires on the cbr TPS in order to get good tps signal. I also suspect that drivability will be extremely poor with the safc...

[wed3k]

ahhh, someones starting the itb stuff.
i might be out of the race due to budget but we'll see.