3S-GE ACIS/Beams discussion, Discussion about ACIS, TVIS, VVT-i, etc. applicable to 3S-GE motors Options

[delusionz]

thats alright

how would i go about modding my ACIS?

rather than tell you how to mod it heres a way how not to mod it
http://toymods.net/forums/showthread.php?t...;highlight=ACIS

(also I recommend a new thread for 3SGE ACIS/Beams discussion)

I've been playing around with ACIS recently and I've discovered a few things about it,

The basics ... when the vacuum diaphragm pulls the throttles, the larger diameter in the corner of the inlet pipes open up (under the lid) for high rpm and when there is no vacuum to pull the throttles are free to return to the constricted low rpm position.

A few problems noted with ACIS:

1. When switching between high and low rpm modes, the vacuum diaphragm sometimes get stuck in the high rpm mode
2. The engage point is too late

First experiment was to see how the car behaved with the throttle pull lever tied up with cable ties as to lock the throttles in the high rpm position,

What I observed with the butt dyno was that under full throttle the rpm range where the car would "suddenly get up and go" was lower down, noticed in terms of road speed 65kph before, 55kph after (2nd gear) so in other words 5000-7000 was the get up and go range, without ACIS constriction in the intake the get up and go range was observed from 4000 to 7000.

No loss in acceleration was noticed from idle to 3000 under part throttle, but loss was noticed under full throttle, between 3000 and 4000 I couldn't tell either way in neither part throttle nor full throttle whether ACIS was better in low rpm or high rpm mode....

This suggests to me that 4000 is a better changeover point than 4800 for performance. 4800 is an rpm not reached by normal driving due to speed limits & gear selection thus ACIS seems to exist for the purpose of keeping intake noise down at legal road speeds rather than for improving low rpm torque as midrange torque takes a hit with this setup.

My proposed solution on how TO mod the ACIS, is to gutt the vacuum actuator system and replace it with a motorised cable pulling actuator triggered by a frequency switch relay at 4000 rpm the signal could be obtained by the ignitor right behind there.

[Rusty]

this from Toyota: The 3rd Generation 3S-GE:

The 3S-GE is an in-line 4 cylinder engine with the cylinders numbered 1-2-3-4 from the front. The cranshaft is supported by 5 bearings inside the crankcase. These bearings are made out of alumium alloy.
The crankcase is integrated with 8 weights for balance. Oil holes are placed inthe centre of the crankshaft to supply oil to the connecting rods, pistons and other components.
The ignition order is 1-3-4-2. The cylinder head is made of of [haha they made a typo] an aluminum alloy, with a cross flow type intake and exhaust layout with a pent roof type combustion chambers. The spark plugs are located in the centre of the combustion chamber.
The intake manifold has 4 independent long ports and utilises the intertial supercharging effect to improve engine tourque at low and mudium speeds.
Both the intake and the exhaust camshafts are driven by a single timing belt. The cam journal is supported at 5 places between the valve lifters of each cylinder and on the front end of the cylinder head. Lubrication of the cam journal and cams is accomplished by oil being supplied through the oil port in the centre of the camshaft.
Adjusting of the valve clearance is done by means of an inner shim type system, in which valves adjusting shims are located below the valve lifters. To replace the shims, the camshafts must be be removed.
Pistons are made of high temperature - resistant aluminum alloy, and a depression is built into the piston head to prevent interface with the valves.
Piston pins are the full-floating type, with the pins fastened to neither the piston boss nor the connecting rod. Instead, snap rings are fitted on both end of the pins, preventing the pins from falling out.
The No.1 compression ring is made of stainless steel and the No.2 compression ring is made of cast iron. The oil ring is made out of stainless steel. The outer diameter of each piston ring is slightly larger than the diameter of the piston and the flexibility of the rings allow the to hug the cylinder walls when they are mounted to the piston. Compression rings No.1 and No.2 work to prevent gas leakage from the cylinder and the oil ring works to scrape oil off the cylinder walls to prevent it from entering the combustion chambers.
The cast iron cylinder block has 4 cylinders which are approximattly twice the length of the piston stroke. The top of each cylinder is closed off by the cylinder head and the lower end of the cylinders become the crankcase, in which the cranksaft is installed. In addition, the cylinder contains a wet jacket, through which coolant is pumped to cool the cylinders.
The No.1 and No.2 oil pans are bolted onto the bottom of the cylinder block. The No.1 oil pan is made of alumimum alloy. The No.2 is an oil reservoir made of pressed steel. The dividing plate also prevents the oil from shifting away from the oil pump suction pipe when the vehicle is stopped suddenly.

Maintance
Oil change: takes 4.5L W/ oil filter change or 5.2L from Dry fill

Compression 1,324 KPA (192psi +) Minimum 1,079KPA (156psi)


more later