03-01-2005, 05:36 PM
I have a question to all of those who know quite a bit about the SVTF. How would I know if there is a prob with my DSI. Right now my car has 5555 miles on it and it seems like the DSI never kicks in. Like when I pass 5200 there isnt a spike in power or a rush of power or anything. The only reason I am asking is becuase ever since I have owned the car it seems like the DSI has never worked. I have heard its like a mild VTEC type of pull. So what should I feel a big pull? How would I see if the DSI is working? Please let me know ASAP becuase this is getting REALLY annoying.
03-01-2005, 06:02 PM
The 03's kicked at 6000ish and you could feel it because the power level was starting to dip, with the YRFO reflash the DSI switched at 5000ish and it produces a more linear power band. The 04's also switch around 5000 so its not as noticable since the engine is still making power instead of starting to loose power.
^^^Correct on all points^^^
If it's working properly, you really won't feel it that much, if at all.
To see if it's working...http://stewartcomputer.com/focusdsi
He provides instructions on how to check it.
I didn't have a 2nd person to help me, so I hooked up my engine analyzer.
I throttled the engine by hand, and checked the tach on the analyzer when I saw the cable move.
03-01-2005, 06:11 PM
should it feel more like a vtec or what because i hear everyone always talking about how they "feel" the dsi kick in??
03-01-2005, 06:15 PM
No because the vtec is a wild agressive style that the cam changes to when the pin is ingaged from oil pressure, the dsi is just a switching from a long runner to short runner, really has nothing to do with cams. For my car it is just a noise and not really a feeling. If you want to really check where the DSI ingages unplug the throttle position sensor and then you will definately hear it. I accidently did this when I put on the throttle body and reved the engine!
While I have no idea what VTEC feels like....
I do know I can't really feel the DSI when it switches at all.
Actually, that's why I finally checked mine like I did.
Have you removed the silencer from the airbox?
If you do, you can hear when the runners switch, though that too is rather subtle.
The intake note takes on a slightly lower "growl" when it kicks in.
03-01-2005, 06:20 PM
yeah i have removed my resonater i dont know i just wish i guess i had more power up top
03-01-2005, 06:24 PM
It's kinda noticable for me, but it's all audible (not felt). I have a Steeda intake and it changes tone at 5000 rpm.
Did a little searching on SVTOA, since I knew there was a good discussion about this.
This is the best explanation I've read yet:
Our two stage intake has two independant torque curves.
When the DSI switches, it jumps between the two torque curves.
You won't feel the jump because the switching point occurs where the two torque curves intersect (an equal T vs. RPM point on each torque curve).
That way, torque is always optimised.
However this assumes you are driving wide open throttle.
If you crossed the threshold at part throttle, maybe you would feel something.
Here's the thread...>>>Clicky (http://www.svtownersassociation.com/svtoaforums/showthread.php?t=4937)
It's a bit long, and "wanders" off topic at one point, but you'll get the picture.[;)]
03-01-2005, 09:41 PM
wow good to know...i recently bought the metal DSI clip being offered on the JET, I plan on putting it in when i get a TB or when the plastic one breaks. Good to know how to check it.