Anyone tried removing the ACIS plate completely?

[ImageMotorsport]

Im curious of what effect/results you recieved..

I have searched and only found info on people that modded them

[94_Toyo_Cam]

what is the acis plate?

[terrastrife]

removing it will work as long as it is OPEN for the higher rpm range in normalworking state.

tony doesnt have an acis anymore.

[ImageMotorsport]

Originally Posted by terrastrife

removing it will work as long as it is OPEN for the higher rpm range in normalworking state.

tony doesnt have an acis anymore.

??

If its gone then how can it be open?

[ag6286]

From what i understand of the ACIS, unless ur doin alot to mod ur car...its not worth the hassle....pro's being slightly more HP, cons being the trouble of doing it and less torque

[terrastrife]

on the 3vz with it gone you get gains all round. it seems on the 1mz that you loose power under 3500rpm though.

[sanengo]

Isn't it backwards? The haynes manual has the opening/closing backwards. Open is low end torque, and Closed is high end power. At least that is what I saw after removing the plate with the ACIS attached.

[ag6286]

it will be closed for more toque and open for more HP

[jackfrost1031]

ACIS Open @ low rpm, closed at high rpm
That's why it has it's own vacuum storage tank. There is no vacuum at high rpm to close the flap.

Easily seen with the engine shut off - the valve is open. With the engine running the valve is still open (The arm hasn't changed)
With the car moving, >4000rpm & >/=50% throttle, the ECU opens the ACIS vacuum switching valve which lets stored vacuum from the vacuum storage tank suck the ACIS actuator open.

[ag6286]

^^^^really?.........which way does the ACIS go in the plenum? based on wut ur saying it runs parallel with the firewall i assume??

what u said is very confusing? u say ther is no vacuum when the car is turned off so it is open...and u say ther is no vacum in high RPM when vacuum to my knowledge Starts around 3000-3500 rpm. Then u say it doesnt open until car is above 4000K or 50%+ throttle

this makes no sense

[HoboJoe]

Originally Posted by terrastrife

on the 3vz with it gone you get gains all round. it seems on the 1mz that you loose power under 3500rpm though.

Really? Gains all around on the 3vz?? I thought you would lose a bunch of torque. Then again, I have no clue.

[ImageMotorsport]

Vacuum decreases as RPM's rise. Thats on every internal combustion chamber engine I've ever seen.

Im not concerning with loosing torque and cant imagine its going to be that large of a loss. I have a hard time keeping the wheels stuck to the ground on a hard launch or around corners as it is so low end torqure is not that big a deal. I would however be happy if I gained more across the band from the better and smoother intake from removing the plate. Plus, the lightweight flywheel will compensate from alot of the torwue loss as well as all the lightweight goodies and mods.

[jackfrost1031]

The vacuum canister stores vacuum.
The VSV opens, allowing the vacuum to pull the ACIS open regardless of engine vacuum.

[brungold]

toysrme said the same thing in the first ACIS
thread.
I asked him about it & he said it's open normally (no vaccum/closed valve/low rpm) & closed for higher rpm/power(when the valve opens & let's the vacuum suck the actuator). He thinks it takes away low end power when it's open to improve gas mileage & it should be shut all the time, or the whole intake rebuilt like Tony the Tiger did.
Here's some pics from him.

[ag6286]

^^ good pics..........this makes much more sense now actually seeing the inside design of the plenum.....i see now y it remains open @ lower RPM.

i do have one question though....is it true the ACIS will remain open if such engines codes as miscomunicating with knock sensor would arise??