Noticed that some 7M-GEs had a single tube intake:
...while others had the ACIS intake:
Has anyone ever tried converting from the regular to ACIS intake? Or vice versa? If so, how big of a difference would it make?
Oh wow, always thought the ACIS butterfly was at the spot where the intake splits into two, at least from what I read from other forum posts about it. Always assumed that plate in that spot was the butterfly valve. These are indeed non-US engines that don't have EGR, Australia got them too so our engine bays are nice and clean
But anyway, when you say air box I'm guessing you're referring to the upper intake manifold? That rectangular plate with the cold start injector right below it, is that the ACIS valve?
Yes, the ACIS flapper is just below the cold-start injector inside the tank/box. The flapper changes the air surge tank (17129) from one big chamber to two smaller ones. 17061A is the vacuum actuator that moves the flap. The VSV is under the surge tank. This control has a vacuum reservoir (25719) because it still needs to move under low vacuum conditions.
Oh wow, actually a fair bit of stuff that has to be changed. Wiring harness too by the looks of things. Would be cool if the ECU already had the programming for the ACIS VSV and all that needed to be done was wiring it up heh. Hoping toyota's fondness of parts commonality would help out here. But at this stage it seems like I'd just be better off advancing the cams a bit for more low end torque and getting a bigger catback for better flow.
Seems like if anyone were to take on this, the main challenges would be wiring up the VSVs and hoping that the ECU already has ACIS programming built in; throttle and (if applicable) trans kickdown cable length; vacuum tank, mount and hosing; and PCV plumbing (although having your own welding tools would make short work of this),