Everyone please ignore Mr. 1970's muscle car, and keep on topic.

I am going to be working on this extensively, so I will post up on new changes, drawings that I get.

 

I think you have a great idea going for you. ITB's in a D16 I would have never thought of it.

Although I have to say there is a lot of thought that would have to be put forth in designing this system. It's not as simple as slap a manifold gasket in between and torque it down. I believe that the vacuum log is good idea. It's looks like everything should work but than again trial and error is the name of the game.

My opinion is some cars have these set ups and it works for them. For example the first car I worked on that had ITB and was FI was the SR20DET from the Nissan Pulsar GTIR in Japan. I had a friend who bought one and dropped it in his 95' Nissan 200SX. That thing was stupid fast. He had it built from top to bottom.

It worked for that engine. Will it work for the Honda? Maybe. Than again Nissan has a lot of engineers working for them thinking this **** up.

You are right there are a lot of factors to mess with. Keep us posted I would love to see how it would come out.

I drive a 2000 Civic Hatch D16Y7. I would like to go FI one day. I HATE ORIGINALITY. I am in the process now of making turbo manifolds. I bought a welder and I am setting up a shop. I say if you want something done right or done better do it your damn self!!!!

Good luck with that.

 

Good luck dude, do you have any "drawings" of what you are thinking the plenum might be?? i have a good web page link to designs to take into consideration and explains what does each measurements on a plenum does, i'm pretty sure you might handle all this, but sometimes reading other peoples view make your view a lot better.

BTW: i know the F2000 or one of those crazy *** formulas races in japan use the plenum that is weird, it's pretty much like the stock plenum but like rounder on the center and the openin is small, off course, this is on a NA engine.

 

Here is a link that has some pics of the 929RR throttle bodies on a ZC. http://www.slebidia.addr.com/itb.htm
I think it is a good idea. As for where you will be needing the most help, the IM, you may want to look at the toyota 1ZZ-FE motor. While it does not have ITBs, it does have a nice equal length long runner intake manifold. It would probably be much easier to go with the all to common "LOG" IM. I would really like to se a nice equal length IM. I mean if you're going all out anyway. Also, IMO, there is alot of power to be gained here at lower boost levels. I salute you.

 

If you're not getting dramatic results with a TB swap on a turbo car (nobody does), then ITBs aren't going to be of any great help. There was no real obstruction there to be rid of with the flow dynamics of the usual TB/plenum setup. Added cost, complexity, and hassle for nearly no gains. The average person cannot use this for all intents and purposes; it's just eye candy.

Still.

3-4% increase in VE would be... not too shabby, as you've stated. There is a potential for gains, especially if you can use cheap motorcycle ITBs and have a DIY bent. It would be mostly in the plenum chamber you'd build to distribute air charge to the ITBs, as you've stated, because the usual system of flow distribution has things so that regular factory TBs aren't a real obstruction.

Most people who argue differ on points of perception and degree... I see the same points of perception that you do, but I'll play devil's advocate in re the degree of success you have out of it. I'm skeptical about it being worth the time and hassle for the gains you'll get.

Regardless of your opinion vs mine, you're gonna learn a LOT from playing with the setup. How do you plan on comparing/contrasting in a scientific fashion, though? Dyno pulls with stock manifold, ported stock manifold, aftermarket manifold (extra $ a problem for you?), and your ITB setup on the same engine with the same turbo? It would also be interesting to see baseline ITB dynos versus more mature results from later in your ponderings. Do you have the sort of time and money for such an exercise, to ensure exactly how valid your gains are?

I know Paul Davenport (929RR ITBs on a D16) was getting WOT readings from the MAP sensor at 25% throttle. A turbo ITB setup would be a real nightmare with the run of the mill T25 or T3 you find on the usual street D16... you'd spool and be boosting at 13% throttle. Time for something... peaky.

 

on my friends 00' corola LE the intake manifold is what i think you guys mean about "reverse equal length". i wish i had a picture to show you. but if you guys go check out a corola, you'll know what i mean. vary good info btw.

 

ok, found the tech article here is the link
http://www.grapeaperacing.com/...s.cfm

Let me know what you think of it.

 

Thought provoking topic, good stuff!

What if a turbo wasn't in the picture, I mean if this same idea was used for a NA setup, would the gains be worthwhile?

 

The comparision is going to have to be thought out. There arent any aftermarket manifolds at the moment, so only direcly comparisions can be drawn from the OEM y8 and z6 manifolds. If an aftermarket one does become available, I might purchase it to do a comparision depending on how good the data looks from the OEM vs ITB results.

As far as added complexity, its going to be alot more complex. I think the reason that nissan didnt go with something similar to this could be the shear fact of production cost. Look at OEM turbo manifolds, then look at aftermarket equal length ones.

The piping will run around 100.00, collector 100.00, vacuum log 30.00, fittings 15.00 and the ITB's were 150.00. For under 400.00 I can make this, and still spend about what an aftermarket piece would run.

This isnt going to be purely guess what works kinda deal. I am going to actually put engineering work into this and let the numbers tell me what set-up looks better. I will probably make two-three different versions to do the comparision if the numbers are coming out similar to see what real world results show.

The engine is fully built d16z6, with a equal length tubular manifold and t3/t4oe 57 trim .63a/r so the turbo is going to be peakier. I am extending the redline to 8,200rpm so I can take advantage of the larger exhaust housing, and the higher rpm breathing capabilites of the ITB's. I have seen itb's running on the stock ecu with zero problems, so I am imaging tuning this with hondata shouldnt be a problem. The vacuum log has to be large enough to give the sensors enough vacuum to operate properly.

 

JalopySiR I used 954RR ITB's on my setup. Slightly larger inner diameter than the 929's.

Boosted Hybird. This was also just a prototype manifold basicly a proof of concept for myself. I did calculate runner length and Airhorn length. I was aiming for an NA peak between 8000-9000 RPMs. You might consider something other than the 929's. Building an airbox around these was a bitch. Tuning is still going to be a problem even with the Hondata. above 3000 RPMs its fine but getting idle and part throttle response has been a bitch so far. I'm idleing with around 11 inches of vacuum.

email me or PM me if you have any Q's.

Paul

http://www.slebidia.addr.com/itb.htm

 

oh man, i had the thought of doing this last year. everyone told me that it would be too tough and wouldnt be worth all the trouble. keep us updated, i want to see how this is going to go.

 

Any idea what your time frame on doing all this is? We all, of course, want instant gratification, but it takes time to do things right, especially if you have work/school/a life to attend to.

I'm playing with the idea of ITBs and NO2 on a friend's D16 right now, all DIY ECU based controls. If you end up with good results I can probably pressure the poor kid to buy all the stuff so I can play with it. Hehe, I'm such a controlling bastard.

 

I wanna pickup a set of these ITBs to play with...should I be looking for specific years?

Suprdave

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted hybrid &raquo;</TD></TR><TR><TD CLASS="quote">

Look how closely the itb's mount up to the d16 head:



</TD></TR></TABLE>

To the exhaust ports???

 

Slebidia: The problem is that you arent getting enough vacuum at the lower vacuum readings, this is obvious since its hard to idle and real light partial throttle is terrible. I am going to counteract this in two ways:

1. Drilling out the stock Honda vacuum nipples, and putting larger units in their places. This will give a stronger vacuum signal to the vacuum box per throttle body.

2. The vacuum log size is critical. I am going to make it fairly large, the dimensions I havent decided upon. Cheetah on h-t uses itb with the stock ecu chipped on many of his customers cars that are daily driven. He claims that the idle and light partial throttle are all dependent upon the size of the vacuum box.

J. Davis: My time frame right now is pretty much to finish up the semester at school. I am finishing off my last rounds of tests, then prepping for finals then I will out for the summer. I am going to work on this project between doing tuning, engine swaps, turbo installs, etc with my business in the summer. Realistically I will have these done when the engine is in the car, probably around july time period. I will def. post up the results.

Superdave: I believe these are off of a 1999 cbr 929 rr. If you are purchasing a set then you can go with the 929 or 954 rr, but make sure that the engine was injected otherwise you are going to be purchasing carbuertor style.

Fucatypr: I wondered if anyone was going to pick up on that when i posted the picture. The engine/head are bare at the moment. I have all the goodies to build them, but i just dont have the time. I have the head resting on the block, so obviously nothing is torqued down. When I took the pic I just reversed the head since I didnt feel like picking up the block and reversing it as well.

I have been reading alot of webpages on how to create plenum's, and went to the library and searched around for fluid dynamics books that can point me in the right direction. With the little time that I have spent thus far I am undecided whether I should go with the reversed equal length style, or the plenum style. The problem with feeding the itb's their own source of airflow is that at lower rpm's the response will be great, but at higher rpm's the resonance from the head will create a turbulence in the runners and possibly affect the way the fuel is being injected, as well as creating a total distrupution to the flow. In that case I might just go with a plenum style. I have to do more research, but I think that the sound resonance from the head is going to play the most critical part in designing this thing properly.

 

There are only a million and one SAE papers on flow dynamics. Sifting through all the NASA and aerospace related crap for the ICE ones was always my problem.

 

Intersting. I may have to give the vacuum log a try. I have a few tweaks I'd like to do on my next manifold also. My original plan was to also incorporate the stock 954RR airbox and just duct cold air into the box from the front of the car. I was about an inch shy of being able to do it. Perhaps it would work in a single cam. If you come up with a good way to mate and airbox to the TB's let me know. I cut part of the back out of the airbox and built the rest of my box around that. I took some pics tonight I'll try to get them up later. As for the low vacuum issue there are also a few other ways to address that. George on the PGMFI board is talking about remapping the ECU to use TPS inputs instead of MAP. I may have to give that a try also.

 

whoooo.. ok now im doing an all motor automatic mini-me. itb's, greddy exhuast, and a full built block.. thank you for the insane inspiration. Where can i get the itb ?

 

i found a pic of a vacuum log while lookin around my files. might be someones car thats a member on here but here it is anyways.

its the cylinder thing on the fire wall with the vacuum lines running to it

 

Tuning off the tps signal is a nightmare. The map sensor gives the easiest/most friendly way to tune it with the stock computer using the stock sensors. Seriously, if you make a vacuum log I can guarentee that you'll car will drive like stock again at idle and light partial.

 

More bike parts on my car. Yeah its a bit ricey but its effective at keeping it quiet. http://www.slebidia.addr.com/can.htm

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted hybrid &raquo;</TD></TR><TR><TD CLASS="quote">Tuning off the tps signal is a nightmare. The map sensor gives the easiest/most friendly way to tune it with the stock computer using the stock sensors. Seriously, if you make a vacuum log I can guarentee that you'll car will drive like stock again at idle and light partial.</TD></TR></TABLE>

No, it will not. You are presuming that each throttle body's runner will be creating a constant vacuum number, as would exist in the plenum of a standard single throttle body system. It will not. Instead, there will be pulsing vacuum from each runner, which will create crossflow in your vacuum log.

 

I have no experiences with itb's on hondas. From what I have read, the vacuum log works. If Cheetah sees this thread, he can comment.

 

since I saw individuals on a Skyline awhile back this idea had come to me also but hell I couldn't make one

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted hybrid &raquo;</TD></TR><TR><TD CLASS="quote">I have no experiences with itb's on hondas. From what I have read, the vacuum log works. If Cheetah sees this thread, he can comment. </TD></TR></TABLE>

I thought about using dual check valves per line but I'm still not entirely sure it would work properly. I'm in the midst of setting up my own ITBs on a B series. I've got a MAF sitting around and I actually thought about it for ~30 seconds.