Possible VG30DE ITBs

[NolimitZ32]

Reading all this talk about ITBs has really gotten me thinking so I started researching ITBs and have come up with a build-able concept for a ITB system. Here is my though process in very short form:

1. The biggest hurdle that must be overcome when running ITBs on a MAF metered system is the MAF or the need to convert to a MAP system, this would require lots of costly mods on the Z32. (So thats out if you want a system that would be cost effective)
2. There are lots of Vacuum driven systems on the Z as well as the IAC system which must have a port to live vacuum behind the throttle plate, adaptations must be made.

I could break these down into many individual points but won't bore you with the details but rather I'd like to pose a few questions for you all.

1. If I were to go ahead and proceed on this little project would anybody be willing to help me test it out on their car, the way I foresee putting this together would require no mods to existing systems or hardware pretty much just pull off your upper plenum, bolt on the ITBs, connect all electrical and vacuum lines and GO.
2. How would you feel about having the ITBs enclosed? I know most talk about the sound (which in my system would be somewhat muffled due to the collector design) I am building these more out of throttle response/performance needs rather than the sweet sweet howl that ITBs are known for.
3. If and thats a big, BIG, IF, at this point. If I were to actually succeed in building a working set that tests well what would be an acceptable price that you would pay for them? Unless I run into some completely unforeseen costs or the world ends, I still plan on building these just out of my own engineering curiosity.

Thanks all for your input.

[300ZXttZMAN]

So are you talking about doing away with the upper plenum all together??

As far as the market i think the Na guys would be more than happy to spend about 1k for the kit or more considering its that big of an upgrade.

Also I would be down to help design the system I belive there would be a fair bit of money involved if you were able to perfect it and make instaltion easy problem is my car is not a NA so you would still need a test subject but what we could do would be to get a lower intake and start fabbing up manifolds, tapping threads, research all for fitment ect. ect.

[300ZXttZMAN]

But also the amount of modification would probably be insane... i think the hardest part of the set up will be the electrical, computer, sensors and effective fuel delivery methods. The easiest part IMO would be the fabrication process and i would be a good person to help because of the tools/equipment and most importantly the sheer number of identical throttle bodys/materials I have... Dont forget my dad and I run a salvage yard

I would wanna see/know/understand your plan in more detail before i agree to join that way i know if it is even a well thought out plan (that is if you would want my help)

[NolimitZ32]

Yeah I'm talking about throwing the upper plenum out and instead setting a transfer plate with ITBs onto the lower plenum.

As far as the design is concerned I'm way ahead of you man, I've already done preliminary schematics for the setup as well as the calculations for runner length. Ideally if this is something that takes off I'd like to get my CNC guy involved in actually making the bodies and all other hardware but the first attempt will most likely be using R6, R1 or GSXR TBs with some modifications. I'm at work with nothing to do so I started thinking and designing and doing the calculations but I don't have the lower plenum here with me (I have an extra one at home) to take all the measurements to actually set the TBs and transfer plate onto the lower plenum so thats the next step.

[300ZXttZMAN]

Well cool im down for the project. Whats the next step?

[nissanfreak12]

I am intrigued by this idea, I know you were talking about tha MAF being an issue. What if you get a stand alone comp to run the engine. I know you want to keep this cost effective, but if the gains are therem, it may be something people would spend the money on. If that is the case, why not just have it run on a map sensor?

If all this has been mentioned, im sorry I must have missed it, sometimes I just read too fast and miss a few things.

[DMeN Z]

[NolimitZ32]

The reason I want to keep it on the MAF is so that you will be able to run the factory ECU with it, basically I want the factory electronics to stay factory, this means making a charge tank/plenum to feed the ITBs, they would be concealed but would still have the noise and the performance hopefully. As far as building a set of ITBs to function with aftermarket standalone all I need to do is make a transfer plate, everything else is cake.

And the next step would be to get all my measurements so I can figure out what TBs I need to make this happen. Like I said I'm doing this more for my own amusement/challenge ATM so we'll see where this goes.

MY biggest problem ATM is figuring out how to make a large enough collection chamber for the ITBs or rather how to make the attachment point for the chamber to the ITBs because having the chamber too small completely negates the advantages of having ITBs.

[canadian booster]

DMeNZ what the sh it is that? it looks crazy!!

[300ZXttZMAN]

ahh I gotcha keep us updated

[Phideaux]

I do have a fully good running NA Engine from my totaled car sitting at home, as the market for selling an NA engine with 140k miles really isn't too big. That being said its open for some sort of crazy project to be done if wanted. Just might need a donor shell to be drive-able/testable , which could probably be done for relatively cheap.

[raremotive]

MY biggest problem ATM is figuring out how to make a large enough collection chamber for the ITBs or rather how to make the attachment point for the chamber to the ITBs because having the chamber too small completely negates the advantages of having ITBs.

Don't tell anyone else I told you this, from the handbook of secrets and rule of thumb has been, total plenum volume should be around 0.8 times the engine size.

Your biggest concern should be runner length and diameter. But you already said you calculated so you should be in good hands.

[DCaff300ZX]

I am VERY interested in a ITB setup for the VG30DE, but am confused as to why you want to add a plenum which will return the system to what is already is except for a throttle body on each intake runner.
Not only that, but the main advantage you get from ITB is the instant throttle response due to no plenum or other air gathering device plus the sound comes from the air accelerating into the ITB, so having a plenum of any type makes it not really a true ITB setup IMO.
Here is what I am interested in (minus the nitrous), and obviously has been done before successfully:

Another company Extrudabody and another named TWM also make similar type setups for many other vehicles, but no one makes anything for Nissan V-6's though...but they do for the VK-56.
I've been told the Escort ITB's were sold in SoCal for a few years many years back so I am surprised a few sets aren't out there running around or that could be copied/improved upon...and if anything nice comes from this I will DEFINITELY be interested.
Oh, the $1,500 price tag seems reasonable if this thing really works, looks good, and especially if it's DIY-able.

[raremotive]

If he rolls without plenum. He loses his way of metering the air through MAF and falls out of his desire to stay with stock ECU.

[DCaff300ZX]

Gotcha Rare...didn't think through the OP's intentions completely.
I'd assume however from the fact Escort was selling theirs it wasn't overly difficult to overcome that issue unless they left all of the setup to you and they simply supplied the ITB hardware...unknown of course since they are not available.
Glad to see you involved in this thread Rare, hopefully you are able to help this idea happen!Timing on this idea is great, as I am finally nearing the engine portion of my Z rebuild and am still really really interested in ITB...

[DCaff300ZX]

OK, I know it's obviously not for VG30, but this prototype seems to be exactly what would work best and be easiest to make with machining and CNC. For VG flip-flop one side to the other and interlock at base for the "crossram" style, two fuel feeds obviously...
VERY simple design:
http://coldfusioncnc.com/index.php?opti ... Itemid=175

[NolimitZ32]

Guys I'm kinda drunk atm so excuse me if I don't make much sense but rare got it right I want a collector on the atmosphere side of the itbs to be able meter the air with the existing system basically making a system that installs without other mods, other than a retune because a factory system doesn't run on MAP and a real itb system would run map bacause there is no place to set a MAF between the atmosphere and head. I'm not gonna go into further detail atm because I'm on my phone and way to inebriated to make sense but I will post tomorrow with some more indepth info. Glad there is interest in this. Thanks for your input guys.

[DCaff300ZX]

Cool man, and by no means feel like I have no interest otherwise...just tossing in my 2 coppers.
I do understand the issues and have been reading up on it all for about two years now from what is available, it's just good that finally someone is looking into producing something ITB for the VG!

[Ace2cool]

I really, really like where this thread is headed.

This + high compression internals + cams = A recipe for awesome. If this I still have my N/A when this comes around, I would be more than happy to be a test mule.

[jona300zx]

I would be willing to get my z to be tested.....

[raremotive]

Before you know it. NoLimitZ32 decides he going to utilize barrel/roller throttle bodies... and have zero restriction at the throttle actuators.... and reap the benefits like the F1 cars and diesels...



I am always complicating things :P

[DCaff300ZX]

OMG...I'm in shock at what we could do here if we decided to just make something completely new here with current technology.
It would take some serious engineering knowledge like obviously Rare and others have and probably a lot of R+D, but holy s***...if we turn the VG30DE into a relevant engine with this it would be SOOOOO cool...

[NolimitZ32]

Hey guys sorry I haven't checked in, Friday night ended very badly or I should say Saturday morning, Ive been pretty incapacitated all weekend but back at it today, I took all the measurements off the lower plenum and also spent some time on my TT. I am now looking for some cheap Motorcycle TBs and talking to my friends that have bikes to see which set I need, basically i am making more in depth drawings (thank you AutoCAD) and looking for more in depth info on the subject, things are progressing.

Jona, I would love it if you were to volunteer your car for the test mule because I'd prefer to be involved in the process fully and that would be difficult if I were to have to send these to one of the other members for testing. No offense guys I love all of you but as the developer on this I need to be there for every stage from start to finish.

[jona300zx]

How long would it take to actually get something going?

[NolimitZ32]

Hopefully I'll have a working prototype before the end of summer. Problem is Ive got a bachelor party, a weddings and 2 birthdays on the weekend over the course of the next 4 weeks so I wont have any time to do major work, but I am doing a little here and there every day at and after work. Jona if you've got other plans for your car than don't worry I might go out and buy a NA if I can find one for cheap just as a second DD/Mule for this and other developments I've got going (since my TT is a swap car).

[jona300zx]

the only thing im concerned about is that the Z is my daily. i dont have other plans than that.

[NolimitZ32]

And thats my other concern, the fact that your Z is your daily it would be a ton of work to pull the upper plenum off, assemble the ITBs test everything, figure out what works and what doesn't (because there's no way everything will work right the first time) then pull the ITBs and reassemble your car so you can drive it to work/school, I can get the fitment figured out using my TT but the final stages of testing should be on a NA even though with the setup I'm going for it would work on a TT as well.

[jona300zx]

We can figure something out...... I am willing to help either way

[NolimitZ32]

Cool, I'll hit you with an update once I get things going.

[Ace2cool]

.....Or you could just buy my 2+2 from me......