Acoustic Induction System... Acis

[AWJ]

The naturally aspirated 2jz-ge engine features a secondary flapper in the intake manifold plenum. It opens for long runner feature at low rpms = torque and closes (I think that is how it works) at higher rpms. I think you guys know I'm pressurizing this system. My question is, Would I benefit by removing this? In the keep it simple approach, this seems to me (ACIS that is) to be a hyped up gimmik providing restriction to flow.

Thoughts?

[AWJ]

something to chew on:

http://www.supraforums.com/forum/showthrea...ustic+induction

[AWJ]

fizzle dizzle

http://www.is300.net/forums/showthread.php...butterfly+knock

Thanks be Gazi

[SKperformance]

great thing to have that is why BMW also has it called vanos

for their variable intake runner

[AWJ]

So it's really not so great but...

well, great for a motor on oem tune.

[SKperformance]

oem mapping ,yes

forced forget about it unless you made a new map to compensate to increase spool rate of a turbo then it would reduce the lag greatly but it would have to be mapped and tuned properly if possible

[AWJ]

Click on the links ... the mechanical action creates a hitting at stop from open and close that is picked up by the knock sensor and timing is pulled. That's a bad thing. The car thinks it's detonating every time that butterfly actuates. You could map it all day long. Even then, to do that would require a complete standalone to even catch that as the cause. It really has nothing to do with spool. But could have everything to do with getting nice smooth curve. My concern was with restriction and loss/gain of torque down low. But with a perceived knock, it's pointless. The last link illustrates this clearly.

[on_chrome]

ahhh...yes, the little flapper, anyway, a guy I knew welded it closed to equilize pressure b/w runners, but hey what does he know... he just has 1000+hp supras all over the place and has directed me to my current 576 hp sc. Anyway, any q's? just ask away or email him at boostlogic.com, his name is chris.

[jzz30]

hehe the guy with the IS is my friend, he came to the shop where i work at to do the turbo, the car is stand alone and that PFS turbo kit costs 10G's! but not worth the money, the kit had all kinds of fitment problems and bad tech support from PFS but after everything got worked out the car was fast! it made 370hp to the wheels and the torque was right there too. its one of those cars that make you go holy sh!@#t as it boosts. but the sad thing is he just sold it a few weeks ago for a big loss, i think he sold it for 28k or something like that. anyway alittle side tracked, he just disconnected the vacume hose and all was fine i dont see haw removing it would hurt if not help.

[AWJ]

Good stuff fellas. jzz30 - I might not mind catching up with that cat on the IS. Did he do his install? I'm not familiar with his build aside from that link to his thread on the mysterious knock issue.

[jzz30]

no our tuner did it, i helped on bits of it but wasnt really the main installer he almost bought a water/methonol injection kit to try and get rid of the knocking but he found the problem.