i was searching and i came across these ITB's they look really sick especially these runners who would this setup work with us FI guys !!

 

Bit late late on this.. It's the Jenvey kit that was shown at PRI. From what i understand those airboxes are made of plastic/fiberglass/something else?, and will not hold boost well.They're plans of being made out of aluminum or steel to handle, Fi applications.

 

Late or not.. that looks like SEX.

 

WOW..put 2 of those on in place of the cosworth....turn up the fuel and go

 

so you have ITBs, then stuff them into a chamber, really, why?

kinda defeats the purpose doesnt it. now you have 2 intake manifolds vs 1.

 

https://my350z.com/forum/shop-builds...th-itbs-8.html

 

NEVA!!! Cosworth FTW!!! LOL

 

In most applications it can actually be more beneficial to have a plenum installed. This will help smooth airflow into the throttles, allows a filter to be easily mounted, protects from higher then ambient underhood temps, and can provide a ram-air effect. You will still get higher RPM power increase due to shorter runners and instantaneous throttle response.

BMW is a liberal user of ITB's in street and race cars. They use plenums in both applications although their race plenums are significantly larger and generally made of CF.

 

I was kind of kidding when I posted that...but after reading the post that Buzzardmountain attached...this looks serious

I am willing to fork out PART of the $$$$ to get this project started if this thing would solve air intake issues PLUS get more or the same power at lower boost

I am talking about a clean setup like the Ferrari, Lambo and Vettes have.

 

itb's can be beneficial for tuning an intake to a specific application.you can play with runner length/dia and taper with limitless posssibility's (unlike o.e).by starting with a blank slate you can make big power,i would enclose them to add the benefit of plenum volume.but the point is that you can do anything you want without counting on someone else's idea of what is appropiate.
the down side is the cost when big #'s have been pulled off of the stock intake and itb's in the wrong hands will be dissapointing.they're cool factor is nice,but not practical for 99.99% of the cars out there.

 

ITBs are nice and all but not really needed. My M Roadster had them from the factory (as do many engines like the 20V 4AGE toyota corollas, etc.) and yeah it sounded great but I'm sure a single throttle body would have worked just as well. More parts = more stuff to go wrong to me. As you can see on the pic of my M below one big plastic plenum with 6 individual throttle bodies attached. Looked cool and all but lots to worry about haha.

mroadster09.jpg?t=1230933351

 

1995 thru 1999 (1992 thru 1999 in Europe) E36 M3 -

US Version - Single Throttle Body - 240HP (3.0L and 3.2L)

Euro Version - ITB's - 286HP ('92 - '95 - 3.0L) to 321HP ('96 - '99 - 3.2L)

 

wow, first time for me to see that. nice piece.

 

it was the sparkplugs

 

SO what VQ setup do you thing would benefit from ITB's

 

An enclosed chamber allows for resonance tuning beyond the runner length and diameters. It's called a resonant, or postive pressure air box. As long as the internal volume is large enough so that a single cylinder gulp doesn't create a large vacuum in the chamber, the pressure inside can be above atmospheric under certain conditions.

Differing chamber volumes have differing resonance frequencies as well. Volume of the chamber can be tuned to try and fatten up certain short rpm ranges. Natural dips in the powerband can be offset a bit, or it can be tuned for max peak power. Theres a lot of uses for having an airbox attached to ITBs, not to mention the ability to use filters.

TK

 

Very well explained... What about boost? Is it possable that you could get more power with less boost or the same power with less boost

 

Positive pressure air boxes work optimally when ducted to some sort forward facing scoop in a high pressure zone. Generally speaking, in a street application, 1-2psi above atmospheric @ 100mph, would be awesome.

Theoretically it's possible, but the R&D cost and time would only be worth it in some spec racing series. Probably for 99.9% of all other applications, it's just easier to turn the boost up 1-2psi. I think it's just more of an NA thing, where every little bit of extra counts. The throttle response benefits would cover all applications though, so there's still advantages to it.

TK

 

Nerd

 

understood, but why go thru the trouble on the VQ of building/installing ITBs, covering them with chambers, then tuning the chambers, instead of just keeping the stock manifold or buying whats out there already. look at the cosworth. lots of $$$ and engineering for minimal gains. just seemed like a lot of trouble for not much gain.