Paulyy

As title says, Who would be interested in an ITB setup or a new Intake manifold?

The big question - What are you willing to pay?

Keeping in mind -
- That the throttle bodies are about $800 for a set of 4. (Australian made and very high quality)
- Plenum may be made from Carbon fiber. OR multi piece cnc machined aluminium.


This is just a feeler as not everyone is willing to spend the money on one, and if it's worth my time trying to make a user friendly one, while i think about making one for my self that will not be user friendly.

rlm328

I might be interested in one dependent on cost. The one Milledge put together was pretty expensive in the end.

Also have a question on boost control with an ITB set up, as the sensor pick ups are usually down stream of the throttle body and with an ITB I would assume it would be upstream. Does this have an impact on the pressure reading.

V2Rocket

Not to throw a wet blanket on this thread, we all love engine ****, but why the effort/expense of making custom throttles when there are thousands of OEM throttle designs available to choose from, that can be made to fit?

Since you're making a custom manifold anyways you can adjust the runners to fit TB spacing and stuff.

Thom

ITBs used with speed density ECUs use a vacuum manifold to balance out the MAP signal as measured after the throttles between each runner.



The MAP signal is always measured after the throttle, regardless how many there are.

AlphaOmegaPower

Talk to MMount. Would definitely be cheaper if we could get commitment. I got his last for my turbo engine. His itb's were made for the 16v though.

gruhsy

Do you have any photos??????

Voith

https://rennlist.com/forums/944-turb...28-4v-itb.html

Itb turbo tuning is tricky, I was advised against it by few tuners.

http://www.motec.com/forum/viewtopic.php?f=39&t=401

Raceboy

It is maybe advised by those who cannot tune it It takes of course more effort compared to plain jane speed density but it works and is definitely worth it.
Have done this and the engine behaviour is absolutely phenomenal, imagine a bike and then there's rush of torque by turbo. Instant throttle response.

Pure speed density sucks with ITB's, it has to be hybrid load (both MAP and TPS are mixed to hybrid load vs rpm). Now you have VE table and then you still need secondary RPM vs MAP fuel table to compensate for different load, then it works perfect in every weather and condition (provided that it is tuned in first place of course).

And boost reference can be taken both before and after throttle, for example VEMS has selection which one is it.

gruhsy

Thanks ya I have seen that thread but no photos of an installed setup

Paulyy

I'm not making custom TBs. They're already made by a company here in Victoria and the quality is amazing. They're actual just individual throttle bodies, no twin or quad housing ect.
Reason is so the runners can be all equal and symmetrical.

I dont know what it'll cost. But i know it's not going to be cheap. It wont surprise me.

I've seen his, Very nice. Even to the point the runners are CNC machined. I probably won't go that far as it'll keep cost a little lower. But at the end of the day ITBS and budget don't go much hand in hand.

I haven't made anything, Couple of drawings on solidworks of plenums designs.
This is where i decide if i want to make something for everyone to use almost bolt up, or for my self where i'll make it work for me only.

i like your attitude. Not to mention, ITBs are good for big cams on the street for partial throttle where the pulses don't get transferred from 1 runner to another.

Voith

I won't be using my 43mm busa itbs so if anybody wants them I've posted them fs in other thread.

Raceboy

For a street car I would not probably bother, I had a dilemma when I had to decide which way to go with my 2.5 16v turbo. Mostly because of space constraint and the urge to get it finally running.

But if the car needs to see track occasionally then ITB+turbo is something I wouldn't want to miss