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]

thats not true, the gen 4 is not a gen4 type with variable cam timing, its a completely different head, nothing between them is compatible, the cam angle is different, the conbustion chamber is completely different , the valves in the beams are bigger as are the buckets. I have one sitting here in bits if an illustration is needed.

There are tuning options for the redtop, i see the name gbooth mentioned, he is the guy to talk to, you can get hold of him through the beams redtop forum and he will supply you with anything you need to tune a redtop or blacktop beams. Cams are not compatible between the red and blacktop though. Its well worth retaining the vvti when tuning it aswell. Theres a 240whp redtop in a gen 5 celica that mr booth built, peak power is at 8600rpm . Theres a lot to be gained from just an aftermarket ecu aswell, my freinds mr2 is putting out 183bhp@7000rpm at the wheels with just intake + decat and ecu.

just wondering if you ment "thats not true, the gen 4 is not a gen3 type with variable cam timing"
I know what your saying, (its just not a gen 3 head painted red) yes it is differnet, but I think what they were simply trying to say was its similar to the 3gen but close up there are quite a few difference as you point out.

by all means post up pics really need more info on here, as there isn't too much floating around, (I can hopfully find the 3gen sizes etc to compare) one thing I really would like to know are the camshaft sizes (duration and lift)
and if you have any more info on the redtop beams ive missed please post it up


delusionz im not to sure, NA require it as this is how they make their power (which is why a 3gen can run up to +300deg cams)

[Edophus]

just wondering if you ment "thats not true, the gen 4 is not a gen3 type with variable cam timing"
I know what your saying, (its just not a gen 3 head painted red) yes it is differnet, but I think what they were simply trying to say was its similar to the 3gen but close up there are quite a few difference as you point out.

by all means post up pics really need more info on here, as there isn't too much floating around, (I can hopfully find the 3gen sizes etc to compare) one thing I really would like to know are the camshaft sizes (duration and lift)
and if you have any more info on the redtop beams ive missed please post it up


delusionz im not to sure, NA require it as this is how they make their power (which is why a 3gen can run up to +300deg cams)

yeah sorry i wasnt having a go at anyone, i'm really not like that its hard sometimes to not sound like that on a forum, i spend a lot of time correcting information about the beams There is of course many similarities between the gen3/4 as in the bucket setup etc

The head i have here is actually from a blacktop beams, but they are the same casting, the only difference being the blacktop has some extra machining done in a couple of spots one of which is the exhaust side vvti solenoid, and the other difference is the machining on the last cam journal on the intake side, both of which is just left undrilled on the redtop, maybe if someone has a gen 3 head we can compare the differences. The only other head i have here is a gen 2 3s-gte which maybe someone is interested in comparing, if so let me know.

Here is a link to some of the tuning parts available, those are the best cams you can get for the redtop, throw out any idea's of using cams similar to those used in the gen3 or other 3s engines as the vvti makes for a very different animal, and you cant use blacktop cams.
http://www.beams-redtop.com/redmods.htm

Gen 4 3S-GE (Redtop) :
Power - 200ps (197bhp) @ 7000rpm
Torque - 21kg-m (152ft.lb) @ 6000rpm
compression ratio - 11:1
Cam duration (IN/EX) - 256°/244° ( timing is -2~43/78~33 thats the vvti range)
Cam lift (IN/EX) - 10.5mm/9.2mm (53/11)
Valve diameter (IN/EX) - 34.5mm/29.5mm
Throttle body diameter - 65mm
Injector size - 340cc (going by the book, flow testing puts them at 315cc)
Notes - VVTI

top of the head - i think overall it is a lot narrower because of the valve angle.


Intake side.


Exhaust side.


Underside.


another shot of the underside, the combustion chambers are about 20cc smaller than those of the previous gens


if you want more pics let me know, the rest of the head is sitting in a box.

This post has been edited by Edophus: Aug 16, 2009 - 6:35 PM

[Rusty]

yeah sorry i wasnt having a go at anyone, i'm really not like that its hard sometimes to not sound like that on a forum, i spend a lot of time correcting information about the beams There is of course many similarities between the gen3/4 as in the bucket setup etc

nah your alright, I know what you mean when you say stuff, the way people interpret what peple say can be different on a forum.

Gen 4 3S-GE (Redtop) :
Power - 200ps (197bhp) @ 7000rpm
Torque - 21kg-m (152ft.lb) @ 6000rpm
compression ratio - 11:1
Cam duration (IN/EX) - 256°/244°
Cam lift (IN/EX) - 10.5mm/9.2mm
Valve diameter (IN/EX) - 34.5mm/29.5mm
Throttle body diameter - 65mm
Injector size - 340cc (going by the book, flow testing puts them at 315cc)
Notes - VVTI

awesome thanks for the specs I was missing, I'll add those to previous info so we dont confuse anyone.

3.gen 3SGE M/T
In: 252deg, 9.8mm lift (timing 7/65)
Ex: 240deg, 8.2mm lift (timing 53/7)
compression 10.3:1
4.gen 3SGE M/T
In: 256deg, 10.5mm lift
Ex: 244deg, 9.2mm lift
compression 11:1

only a slight increase between them, but that would explain the 19BHP difference



http://www.trdparts.jp/english/parts_engine-3s-ge.html
that one off hole (oil hole) inbetween cylinder 1 & 2 is for controling vvti right on the blacktop? same on the redtop or is it that extra machinering your talking about?

[Edophus]

that one off hole (oil hole) inbetween cylinder 1 & 2 is for controling vvti right on the blacktop? same on the redtop or is it that extra machinering your talking about?

thats there on both, i assume on the blacktop it just feeds both solenoids, whilst on the redtop just feeds the one. The extra machining i'll highlight on those pics at some point but busy at work right now!