ACIS 'power' mod

[NTL]

I'm just wondering if anyone here tried this with their Camry.
This will ONLY work on the 1MZ-FE V6 engine.

(All credit goes to the original thread maker.)

http://www.solaraguy.org/viewtopic.php?t=23181

Heres a tutorial with pictures on how its done.

http://www.solaraguy.org/viewtopic.php?t=23293

I did this 'mod' yesterday. Yes, it is noticeably louder when I free rev while stopped, below 4k rpms. Power-wise... it felt nearly the same. I did do a few 0-60 runs with a stopwatch (yea I know not accurate). The times were consistently faster with the stock setup than with that acis mod (roughly 0.4-0.5 seconds slower to 60 with acis mod). I know I havent lossed power on the lowend cause stock, when I stomp the gas from a standstill, the tires will spin up to a little past 3k rpm before catching traction. After the mod it still does the same. When I had my ebay intake installed it would feel really sluggish and barely spin the tires past 2k from standstill, so I know what loss of lowend power feels like.

Anyone wanna give this mod a test and report back with results? It seems totally reversible and takes only a few minutes to do. Maybe someone knowledgeable with this acis can explain whats happening and maybe tell me why its making my car slower when people say you gain power.

[terrastrife]

intake runner length changes (shortens when closed/activated). the ACIS is to keep intake roar down at cruising speeds (Acoustic Control Induction System), this is why it also does not activate at over 3800rpm with low tps.

we've all done this years ago =)

the easiest way to do this is quite simply to zip tie the actuator permanently activated =)

[NTL]

Ok so it makes the car slightly louder at lower rpms, what does it do performance-wise? Does it make (or lose) any power in the low, mid, or high rpms?

[terrastrife]

mid range gain (2000-4000rpm)
low end loss (under 2000)
nothing up top (over 4000)

the loss is due to the runner now being a tad too short to make power low ^^ if youve ever looked inside the intake plenum, youll see that it is almost solid filled (the forming of the runners), only about half of it has actual volume.

when the acis activates, it makes the runner lengt shorter (the butterfly valve closes and removes a part of the runner length)

ideally youd want it to activate around 2000rpm, which can be done by running it off the intake vacuum.

[NTL]

Well I searched around and came across this:

1.The ACIS allows the intake manifold to divert the path of intake air into the combustion chamber. Two air intake paths are provided in the intake manifold to allow the option of the intake volume most favorable for the particular engine speed. Optimum performance is achieved by switching the intake air control valve from either the closed postion(for high tourque at low rpm) or the open position(for maximum horsepower at high rpms).

this information was taken from a haynes manual on page 6-15

If that mod forces it closed at all times wouldn't it lose power slightly in the high end?

Like I said, I felt no difference in power on the low end but something is causing my car to be consistently slower overall after doing the mod while doing timed runs.

Anyone else wanna try it out and take your camry out for a spin? Maybe do a few timed runs to make sure im not imagining things.

Thanks for the input though terrastrife.

[terrastrife]

that info is wrong.

if you actaully bother to LOOK at the butteryfly. and if you actually read what ACIS means.

if your vacuum hose is collapsing (under vacuum) then you will loose power as the butterfly re opens when its supposed to be closed. <-- this is the main reason/problem that most ppl get.

i know what im on about. the haynes manual doesnt know wtf its on about. sure, its theory is right, but in practice the vsv switches the actuator TOO LATE. the butterfly should be closing at around 2000rpm for the engine to use the shorter intake runner length. this is the reason you see the drop of power between the 2000rpm peak and the 4000rpm peak... in dyno charts...that SHOULDNT BE THERE, and it IS NOT there with the the switching done earlier, or permanently.


heres what i was looking for


see torque dip? all gone with acis closed.
another bit to explain, the torque flatness before 2600rpm is due to the stall not being locked yet as well, im pretty sure. thats why as soon as the auto locks the torque jumps to what it should be.... which is why auto 3vzfe's suck =)

[2wickedtoyz]

i made a post about this a few years back.

http://www.toyotanation.com/forum/t45066.html

[Eye8Pussies]

holy thread revival batman!