For those with the 3 Stage Manifold swap

[Taskmaster]

Can you feel the power bump at 2.8-3K?
Does it feel like it levels off and/or stays the same after that?
Is there a huge jump at around 4500rpm?

I'm asking because my powerband AND dyno were screwy.

[TheSt|G]

The noticeable bump for me is the 4k-4.5k rush. You should be able to hear the manifold flaps adjusting, and then a power change right after.

[631twentyeighteye]

Short answer, yes. I noticed a big difference 2-4.5k RPM. I don't know when the DISA flaps open/close or when they change although i could hear them working prior to catless headers(too loud to hear now). There is way more torque and usable power around town. Up top it pulls very similar to stock fashion albeit with more power overall.

Post up your dyno sheet, i'm curious to see what you mean. I don't really notice any dips in power that i thought i'd get when swapping to the DISA. I don't notice any on the dyno graph either but the scale is a bit off so it could be hiding them.

[Taskmaster]

I don't hear them at all, but I feel the torque bump at around 2500RPM-3000RPM, it levels off and then I feel a small dip around 42-4500RPM and the Rush afterwards.

The dyno (which I'll post in a few) shows looks odd -There is a torque hump at 2800rpm, then it flattens out and finally peak torque is at 4600rpm and is a straight line until the power peak at 6200rpm.

I uninstalled the tune and the feeling is the same (less poweful obviously) so I think there might be an issue with the DISA valves/oring gaskets.

[Taskmaster]

Anyone have Winpep and want to post it up for me? I'm at work.

[kobeballer96]

I feel the dip on power but I'm not tune yet, I know exactly what you mean.

[Taskmaster]

Notes:

Done on a different (lower reading apparently) dyno than the others
Not done in the same gear
RPM hookup/ignition hookup could have been wrong (they admitted they weren't too sure, they specialize in American cars)
No A/F reading

[Taskmaster]

This doesn't look right at all, especially where my mid range power is missing. I've seen this one time before this, when I dyno tested my M52TU Z3 (with a 2 stage DISA)


The huge increase is after I replaced the DISA valve (the small increase in high end hp is from underdrive pulleys)

[Taskmaster]

Anyone? What does the DISA sound like when it activates?
I think mine is broken, I'll try removing it and seeing what is up.

[TheSt|G]

Originally Posted by TheAxiom

Anyone? What does the DISA sound like when it activates?
I think mine is broken, I'll try removing it and seeing what is up.

A click and a hiss as the airflow pattern changes.

[Taskmaster]

Well at least one of them seems to be working, you can see the power fall off after the first torque peak at about 3K - after that, there should be another hump - and instead there is a large flatspot, until about 4200rpm and then the car gains power all the way until 6200RPM.

So which DISA is responsible for the Middle power hump? I think it's the one by the throttle body, but I can't be sure.

Anyone know how to test them?

[TheSt|G]

Volt meter would be a good starting point.

[Taskmaster]

Originally Posted by TheSt|G

Volt meter would be a good starting point.

Do you think it's possible to mix up the DISA wires?

[TheSt|G]

Originally Posted by TheAxiom

Do you think it's possible to mix up the DISA wires?

I didn't try swapping them, so not sure frankly. You could cross check the length of the wire with my install thread. There is a picture of them side by side in there IIRC.

[Taskmaster]

Found the problem I believe - DISA #1 is stuck in the open position.