Individual Throttle Bodies - Knowledge anyone?
 

Hi all

I'm doing a bit of research into ITB setups, and while I have found a few forums on the net that talk about them, I can't judge their accuracy that well. I would have to imagine one of the many gurus on PDiddy would have some idea about them, in relation to benefit/gain or cons? At this stage it's merely a thought I'm considering in the lead up to my journey to the workshop.

Much love

Alex :p

EDIT: I should specify this isn't for a Subaru, so more general issues, as opposed to individual engine types.

My R32 Gtr has ITB's (they're standard), they suck to resynchronize after having them off to replace a leaking manifold gasket..... Still not 100% but I've given up after looking at it on and off for 2 years....Using a carb syncronizer is no help in my situation as theres only 1 vacuum port on the front throttle body pair on the R32.

Yeh, I was under the impression that a few Nissan models run ITB's. (GTi_R as well?)
I've heard of a few Jap teams that change the GTR ITB's over to a large single, but as this is a ground up build, as opposed to a factory item I wasn't too sure as to whether they'd be a worthwhile investment. Still just an idea at this present stage.

What sort of car/motor is getting the ITB setup?

If its V8 there is plenty of options... Hilborn, Enderle, EFI hardware....
Not so sure what options there is for 4's & 6's
It really comes down to what application its for and how far you are willing to go to make it work. :)

If it's naturally aspirated and you expect big revs, like power over 7000 it's probably a worthwhile excersise. Unless you're going to run some big cams, big comp and rev the freckle off it then it wouldn't be on my shopping list.

*Engine as above will sound awesome.....no question!

PROS:
Increased throttle response
An equal air/fuel mix in each cylinder assuming everything is as it should be
The induction sound really does make the bitches wet
Skids will be had

CONS:
Cost to set up
Cost to maintain (as Ross has already mentioned)
New inlet manifold will be needed, along with a host of custom parts if it isn't a conversion done that many times there is an off the shelf kit available
Kiss your IM240 (emissions) test results goodbye
Also I wouldn't worry about it being able to pass a drive-by noise test anymore
Fuel consumption will go up

Thanks for the information. It's for a Z18/24 injected turbo datsun. The cost of it isn't something of real concern so I don't really have a drama with that side of it. But the legalities could be of concern. I knew I'd find some decent responses on here.

Cheers guys.

Z series Datto has a fairly poor port shape and basic combustion chamber. Not ideally suited like a hemi chamber DOHC set up. It may make a small difference, but don't expect miracles as the air's being blown in by the turbo anyway. Bigger benefits are usually found on N/A engines where you're trying to fill the cylinder at high revs with no extra pressure. If you want to do it just for the sake of it try buying a DCOE Weber inlet manifold and some Weber pattern throttle bodies. You will then need to fabricate an airbox that will bring the 4 inlets to one anyway. Problems I see are insufficient room between the strut tower (in a Datsun) and the turbo killing all the inlet noise that's usually the desired effect of the ITB's. I would think that the exhaust emissions would be lower than a similar engine with carbs, so you may be ok depending on the vehicle age.

Perhaps look at adapting the Corolla hatch ITB's to the nissan head?

**Edited I didn't read it was a turbo Z24.**

Ala Toyota 4AGE style:

[IMG]http://www.my-acoustic.com/Car/vacuum/4_throttles'_vacuum/4_throttles.JPG[/IMG]

Building a custom plenum for a turbo application will suck though!

whenever i hear 'ITB's' and 'datsun' it reminds me of the 500zx...

[url]http://www.youtube.com/watch?v=ncxR7xNcSfI[/url]