Re: The ITB info thread.
 

you should be able to see 15 whp with an itb set up on a stock d16y8. The skunk2 manifold is good for well looks. If you wanna do a manifold upgrade a factory ported unit with a bored tb will make more power where it counts than the skunk manifolds that are meant for well high rpm d series motors which are well like 1 percent of them.

Re: The ITB info thread.
 

so basically i have some packing and shipping to do.. well when the time comes it will be at your door step

Re: The ITB info thread.
 

D-series ports are too small to support past 8500 rpm regardless of cam selection. The sort of talented porter who can perform fisty on a D head without killing off flow quality costs some ------- dollars, ESPECIALLY since oversized valves are just shrouded by the tiny bore. High rpm D-series are expensive toys owned by freakshow nutjobs.

I'd love to own one.

Re: The ITB info thread.
 

Stock cam works really ------- well to 8400 in a Y8, I wish I had ELspools dynograph to show you, it's no 2.0L B, but it's quality none the less.

Re: The ITB info thread.
 

Big boost projects the cam's powerband upward, the more you crank the boost controller the higher your powerband is. Look at GSR and ITR making great power at 9500 rpms.

Re: The ITB info thread.
 

Makes sense, 23 psi from a T3/T67 or T61 forget which. Torque curve is a line from 5500-8400.

Re: The ITB info thread.
 

im no tlooking for anything crazy just a little extra to get it going faster.. i have the y7 trans now which is geared to long and want the y8 trans which i know would wake it up some but just looking for more in the bolt-on category so i dont get extreme with this and have loads of down time

Re: The ITB info thread.
 

the y8 trans will be worth every penny. For ease of tune/blot on action stock ported manifold/tb for the win. Itb's take a little time to get dialed in and most people still dont tune them which is why the rumors of them being non streetable began

Re: The ITB info thread.
 

Chris, that first set you did turned out just right. I'm sure the subsequent sets you've put together have been even better.

I still remember those 38mm cbr's I put together ages ago. The throttle response was instant. And, no codes, even on the pg7 map you gave me back in the day. I've got a set of 929's in the garage. I'm going to be making another set for the 76mm pg6b'd block downstairs. I simply need to find a set of the stock velocity stacks, as the seller didn't think to send them to me with the throttlebodies themselves.

Re: The ITB info thread.
 

yeah im willing to pay alot for that on the H, if i can get get itb's on my h, then ill be the happiest man alive

Re: The ITB info thread.
 

pm me for pricing

Re: The ITB info thread.
 

Ya the next set is pretty big step up. Busa's bored to 48mm plates. Already have a some thoughts on stacks for them. I also have a flowbench access now so testing will be done has well on them. Of course all for a b16a head my fav.



Manifold design is a little different I have only done stuff on paper etc but it should work. All the itb's I have done I have gotten port allignment damn close on them these I want dead on




Pics will be up once im done with them along with some flow #'s on a stock b16a intake port

Re: The ITB info thread.
 

How bad of a difference is it if the ports aren't in a direct straight line with the TB's? I had my neighbor behind me tig up some tubing onto my old b16a intake I cut up, and the 2 outside ones must of moved a bit when he was welding. :-\

Re: The ITB info thread.
 

well if its a couple mm thats starving that cylinder for sure. Thats why most of these people do kinda suck imo. Test fitting and port matching is key. If its just a hair off just bust out the die grinder and blend it in if its more than a mm well you could run with it if its already done

Re: The ITB info thread.
 

well i have decided to throw some zc pistons and rods in my spare y8 block for a bit of a compression bump goign to hrow a zex cam in the y8 head get a header and get an itb set-up going.. what woudl you recommened going with as far as throttle body size for basicall stock y8?? i was thinking 1000cc gsxr ones possibly even busa ones.. tell me if im going in the right direction

Re: The ITB info thread.
 

either would be a solid choice. The busa itb's need port work on them to perform over the gsxr 1000's

Re: The ITB info thread.
 

Yeah I think I'm going to take a die grinder to the back side of mine to open them up a bit. Where it tapers down just screams restriction to me. :-\

Re: The ITB info thread.
 

45mm plate on the busa and tapers to 42mm :1. Looks like you can bore the back side to around 45mm keeping enough material that is safe


I already started on my set that will retian the stock plates. Already got the 48mm plates being made :)




I cant wait to get it all done. Reving the piss out of b16a on itbs makes me a happy happy man

Re: The ITB info thread.
 

Sweet! That's what I'm talking about, and if worse comes to worse there's a bike performance shop at the end of town that said they can bore them out and make new throttle plates for me too. The funny look on their faces was priceless when I told them what it was for though. ;D

And let me know if you have anything on that throttle linkage assembly. ;)

Re: The ITB info thread.
 

45mm is plenty for your typical street b series motor. I looked through my pile and couldnt find anything sorry must of thrown it away on my move

Re: The ITB info thread.
 

hello,

i'm Tom and live in Belgium.
i have a honda crx with
b18c6 engine
blox cams
unichip

i made these ITB's (with gsx-r 2001 itb's) and with the gsx-r airbox! we have tested on a dyno without the airbox and that resulted in a hp drop (-15ph all over the line).
so without the airbox it realy doesn't work.

http://img505.imageshack.us/img505/486/itbsif8.jpg
Shot with FinePix S5600 at 2007-08-15

http://img505.imageshack.us/img505/7670/itbs2gi5.jpg
Shot with FinePix S5600 at 2007-08-15

http://img521.imageshack.us/img521/2078/itbs3wk9.jpg
Shot with FinePix S5600 at 2007-08-15

result:

the car is faster: 1/4 mile in 13.2 sec (before it was 13.6 sec)

bleu: withe aem cold air intake, 60mm tb, skunk2 inlet manifold
red: with suzuki gsx-r itb's and airbox with k&n filter
(torque in Nm, and flywheelhp)

http://img521.imageshack.us/img521/2...rkleindor0.jpg
Shot with FinePix S5600 at 2007-08-15

Re: The ITB info thread.
 

chris you said you were working on an itb set up for a ZC i know the factory plenum gets chopped off right at the fuel rail studs,but my question is what would be ideal runner length and size? also with gsxr1000's is there going to be any port match to them to get them fitted right? i am thinking of taking this project on my own just to also say that i did it.. any of yours or JD's input is greatly appreciated..

Re: The ITB info thread.
 

I'm assuming you tested the itb's with the airhorns on? Or just ran them without for the dyno run? FYI, the airhorns contribute to the overall length of the runner, and something about the curved lip of the airhorn is supposed to help "pressurize" the runner. It also looks like your itb's are slanted downward which probably doesn't help much either.
If I ever get to finish my ls/vtec and my itb's I'll have to look into the differences of running an air box on there compared to without.

Re: The ITB info thread.
 

yes, i tested with the airhorns on.

the itb's are straight on the block. so they go a little bit upward because the block turns over to the front.

Re: The ITB info thread.
 

Here's the cbr 929's I've been putting together. I'm using the injector bosses for vacuum. That leads to the fuel rail/vac manifold, and then to the accessories. The velocity stacks are from my local VW shop, typically used for certain weber or dellorto carbs. I think I'll smear some rtv in the groove between the v-stack and the throttle bodies to smooth the transition.

I need a y8 manifold/fuel rail setup if someone has one that they don't want 80 bucks for.

Attachment 24846

Attachment 24847

Attachment 24848

Attachment 24849

Attachment 24850

Attachment 24851

Re: The ITB info thread.
 

Looks good Josh. Only problem with the gsxr is the size of the inlet on them. 50mm id od is around 54mm so finding a velocity stack that doesnt cause an issue with restriction is a major issue. Alot of the old stacks designed around the older carb era bikes seem to work well with some mods has they have large horns

Re: The ITB info thread.
 

why does nobody use the 4age 20v ITBs? they are on a "160hp" na 1.6 liter engine already... and they are cheap cheap cheap. im sure everyone has seen my pictures smeared all across this website so ill keep it to a minimum...

http://img.photobucket.com/albums/v1...e/DSCN0401.jpg
http://img.photobucket.com/albums/v1...e/DSCN0600.jpg
http://img.photobucket.com/albums/v1.../6-5-06065.jpg

http://img.photobucket.com/albums/v1...-5-06006-1.jpg
http://img.photobucket.com/albums/v1...-5-06005-1.jpg
http://img.photobucket.com/albums/v1...-5-06002-2.jpg

and ill throw these in for all to see... does this count as porn?
http://img.photobucket.com/albums/v1...Picture821.jpg

Re: The ITB info thread.
 

wow that's quite a difference. i'm a bit of a noob when it comes to itbs, how is it that the itbs produced such a significantly smoother curve?

Re: The ITB info thread.
 

with a normal (cold) air intake you have more resonance in the airflow.

Re: The ITB info thread.
 

"more" ?

Re: The ITB info thread.
 

wow those look very clean. i still think im just gonna beg and wait for twm to make some d-series itb's

Re: The ITB info thread.
 

twm produced d series stuff back in the 90's. The future in all motor is k series. They will never develop anything again. Make a custom set only choice

Re: The ITB info thread.
 

actually ive found another way. you can get a carb manifold for the d. then get carb replacment throttle bodies. :1 the only way ive found to get some 50mm itb's.

Re: The ITB info thread.
 

nothing new I did that like 5 years ago

Re: The ITB info thread.
 

Here's mine almost done
Attachment 23588
Attachment 23589
Attachment 23590

Re: The ITB info thread.
 

hey guys im new here i was referd to u guys from d-series.org bout buying a set of resdy to bolt on itbs 4 my sohc.can anyone help me please?

Re: The ITB info thread.
 

550 shipped


my work can be seen in this thread

Re: The ITB info thread.
 

b18b1 set installed


http://img138.imageshack.us/img138/2623/itbtt8.th.jpg

Re: The ITB info thread.
 

nice as usual.. ok quick Q's.. currently i am working on a 12:.1:1 mini me using a6 block,p29 pistons and z6 head.. what would be optimal Tb size for my particular combo.. i have the runner length down and everything else just lookin gfor optimal sizing.. i want to be in the 180whp range..after i add the cam and spring/retainer combo for reving out to 8200.. i know for my combo with cam and itb's it is VERY likely to hit around hat mark with a good tune

Re: The ITB info thread.
 

The huybusa will be your best bet. They have a 45mm plate but taper down to a 42mm base that needs to be ported out to make it use the full length of the size of the plate. Now getting your hands on a set isnt that easy but can be done. I have an extra set if intrested