Ffim ge?

[zby67]

Originally Posted by btwilson86

I personally like them on a GTE, but I would advise against it on a GE. Couple big reasons is that the ACIS system will no longer work (or be there), and I would think that the rear cylinders will be starved for air due to the increased distance air would have to travel after entering the FFIM (this will also reduce the air velocity thanks to the 90ish degree turns the air has to make to enter the plenum runners). So basically you'll lose some significant power/performance.

These tend to work okay on turbo models because the boosted air will pressurize the intake manifold so air will be readily available for all cylinders.

Stick with the GE manifold. It's design is one of the best possible ways to disperse air in a fuel injected inline engine. Besides, the heat transfer from traveling over the exhaust manifold/headers and engine is minuscule.

ok thank you for the info! thats the one of the answers i was looking for. also how does ACIS work? i would like to under stand that better so if you have a link that would be sweet!!! as it stand right now making my 87 into my project car would be a bad idea. so ill take the two GE's i have make one fix what parts of the body are needed and gut the 86 junk it and make the 87 my DD and wait till i get the 90 supra i want for the project car.

[907mge]

The ACIS controls a butterfly inside the main section of the intake manifold(under the plate with 6 srews) that will shut at a certain rpm seperating the manifold in 2. It is controled by a vsv and a vaccuum canister that is controled by the ecu. I don't remember the right rpm though. But what is does is keeps the air from each side of the y-pipe seperate and flowing into 3 runners each instead of a open chamber of 6 runners. I think the whole purpose is to reduce turbulance in the air flow being sucked in. This is why the turbo does not have one since it is forced induction and not natural aspiration.

[cre]

It's an acoustic modulation device. As valves open and close there are rebounding waves of air which pulsate back. These pulsations affect air velocity and density. Depending on how much air it's pressing back into the affect is different and the amplitude of the change varies. <--- going from memory on this, my memory of it is a bit rusty.

It activates at 4200RPM and around 70% throttle.

[zby67]

Originally Posted by 907mge

The ACIS controls a butterfly inside the main section of the intake manifold(under the plate with 6 srews) that will shut at a certain rpm seperating the manifold in 2. It is controled by a vsv and a vaccuum canister that is controled by the ecu. I don't remember the right rpm though. But what is does is keeps the air from each side of the y-pipe seperate and flowing into 3 runners each instead of a open chamber of 6 runners. I think the whole purpose is to reduce turbulance in the air flow being sucked in. This is why the turbo does not have one since it is forced induction and not natural aspiration.

ok now i get what that valve in the plenum is for. thank you for the info! +1

[cre]

Think very early V-Tec... Air flow is cleverly modulated and timing is adjusted. It affects how the car performs at lower loads granting more torque. If you swap in a Cressida GE and don't swap over the intake or install a Cressie ECU you'll find you lose a good amount of power off the bottom end... Cressie's don't have ACIS.