Acis valve and supercharging
Acis valve and supercharging
hi all.
I did some research about the acis valve and intake manifolds and found some interesting topics.
here some explainations what the acis and tvis from toyota does.
http://turbomr2.com/MR2/Reference/TVIS/TVIS.htm
here some interesting dyno measurings with diffrent opening timings.
http://www.tercelreference.com/articles/...tions.html
Now i am still curious. I now that with the acis valve in the intake manifold. below the 4200 rpm and with 60% or more open throttle the valve is closed. The rest of the time the valve is open.
So when the valve is closed the intake manifold is split in 2 halfs. The air has a longer path to travel through longer runners so the air has more speed and this will result in more torque in the lower rpms.
When the valve is open the air goes through a shorther path and this will give better torque in the higher rpms.
Now this works all very well with naturally aspired N/A engine but since i am running a supercharger setup on my is200 i am wondering if it would be better to leave the acis like oem or lock the valve to permanently open.
The thing is and this is really whats confusing me is. I have been experimenting with this valve. I locked the valve to permanently open just with a tiewrap.
With the oem setup my peak boost was 0,6 bar near the rev limit.
When I permanently open the valve my peak boost is 0,7 bar around 4500 rpm and then goes to 0,6 bar till the rev limit.
So in the end with just locking the valve to permanently open is 0,1 bar increased boost. I cannot really feel the diffrence when i am driving but I found this very interesting.
On one side when i read all the articles it looks like the ACIS still works under boost but on the other side when i disable the ACIS I get 0,1 bar more boost.
So are there some people who has experimented with this. Or someone who has some dyno results with this.
I am gonna have my car mapped on september the 26th and i am gonna ask them if they could do a run on the dyno with the valve permanently open and a run with oem setup. I am very curious if this does affect the dyno results.
forgot this website. Also nice infotmation
http://www.autozine.org/technical_school...haust.html