wtf is this gizzmo? tvis?

[sam-131]

well after inspecting the intake and thinking of a way to chop it to suit the gixer carbies i took the top part of the intake off thinking it's removable for inspecting purposes but look what i found it seems to be some sort of gizzmo to create more pressure or less but i havent got the faintest idea wtf it is

tvis possibly?

here are the pics







so yeh wtf is it and whats it purpose ?hmm off a mr2 sw20 3sge gen2 92

thanks Sam

[mullett]

looks to me like quad throttle bodies...

RM.

[AndyTTR]

not sure what they called it on the gen 2, but the gen 3 has a similar setup called ACIS (accousitcally controlled induction system.

Google says:

Acoustic Control Induction System (ACIS)

Two and three stage Acoustic Control Induction Systems can be found on various Toyota models. Both systems operate on the same principles, however the 3-stage system is able to tune the intake manifold to 3 lengths instead of 2. 3-stage Acoustic Control Induction System (ACIS) uses two valves inside the air intake manifold to create the effect of 3 intake runner lengths. The ECM is able to select from these 3 lengths to effectively tune the intake manifold to engine operating conditions so that a pulse of high intake pressure is immediately available when the intake valve opens. The engine uses these high-pressure pulses to pull an unusually large volume of air/fuel mixture into the combustion chamber, effectively supercharging the engine and increasing torque.
Benefit: Increases power output at all speeds

Also found a mention of it on autoshop101.com about the ECU advancing the ignition timing when ACIS kicks in.

I was originally told it was somthing like TVIS, but the system is clearly something completely different.

[sam-131]

nah they aint quads they could be use as such with a bit of modding but it goes no were

there also vac operated and it mounts to the top of the intake

more pics

[sam-131]

ah sweat i'll think i'll gut it seeing it wount be able to run with the carbies but thanks a million

[AndyTTR]

no worries man, i learned something too.

Just for reference, here's some pics of the gen 3 set-up.

[c2888]

Butterflies closed
it looks like the inlet runners would take the long path, from the plenum, to the inlet valve.

so it's a 4 runner, really long inlet, small plenum manifold



Butterflies open
with the butterflies open, the chamber combines all of the runners, so air can and will go across from no4 to no1 or which ever way it pleases through the chamber.
This kinda turns the top runners into a giant plenum, well bigger. So now the inlet runner length begins where the two sections join.




So it's a variable intake, on a toyota motor, so it's still a tvis of sorts.

dan

[ReQuieM]

^ what he said except they are variable length runners not plenum. harmonic pulse hits the pre-plenum plenum then bounces back making short runners. See my post in the plenum size thread for more ont eh pulses. It must be set up to change at a certain vacum setting. weird. Maybe the vacum is an indcation of the right rpm to change the runner length for top end 'tuning'. Cool, nice to see a toyota stock setup. Seen a perfomence set up the used two sets of runners from a shared plenum. butterflys were at point where they merged, just before the injectors/head.

[WindeX]

It is the ACIS system, if you remove it dont keep the stock manifold, I have a TA23 with a gen2 3sge in it and it has quite peaky power, which is a sympton of removing ACIS.

[sam-131]

in all seriousness i carnt be farked making a custom intake for the daily/hack i just want the thing running and i carnt be bothered trying to hook up the ACIS with the gixxer carbs

anyway whats worng with a peakyer engine