VRIS Controller Review....

[Bri94GS]

So will this work with a k8 or not? I'd be interested in a group buy if it was. I'm sure tons of people would be interested, it's not that expensive.

[IanL]

I'm sure someone will correct me if I'm wrong, but I think this is not aimed at the K8 engine. The idea is to be able to set the VRIS points in a non-factory setup (a hybrid), like a KLZE with a US Millenia IM, for which you cannot buy an ECU with the exact VRIS points. If you have a K8, you have the right VRIS points in your ECU, so how is it going to help?

[Bri94GS]

Wouldn't you still be able to adjust when the VRIS kicks in?

[IanL]

That's what they say, but they don't explain why you should expect to benefit from doing so.

[MazdaManiacMx3]

I'm to skeptical lol . I'm just going to spend the money on some side skirts .
I dont think this will benefit me either I will be running a 2.5 with bolt on's .
Kris

[Bri94GS]

I was just curious to see if it would add more power to the car if the VRIS kicked in at diff rpms. That lovely boost towards 5k is nice, would I be able to start that boost around 3k? I don't really know much about the VRIS system or how it functions.

[IanL]

The VRIS works by minimising the impedance to gas flow, using a resonance effect. Its analogous to resonance in an electronic circuit (if you're into that), when the impedance in the circuit can drop to a very low level at a particular frequency - the "resonant frequency". The variable corresponding to frequency in our engine is rpm, and the tuning is done by varying the inlet geometry with the VRIS shutters. For a particular design of engine, there will be a number of values of rpm where the VRIS effect is maintained by switching the geometry through the rev range.<p>The only way those points could be moved (and still get the benefit of VRIS) would be if the physical geometry of the inlet tract were to change (e.g different IM or TB). What you would do is to make the physical change(s), then do four dyno runs, with:<p>#1 Open, #2 Closed
#2 Open, #1 Closed
Both Open
Both Closed<p>You plot the four torque curves, one over the other (see page F2-100) and you'll see where to place the VRIS change points to "ride the high curve" all the way up the rev range. <p>The point I'm making is that the engine determines where the VRIS points have to be; if you just decide you want them to be different, you lose the high curve.

[Bri94GS]

There's a place with a dyno not too far from my house. Do you think the VRIS points would need to be moved in order to attain full power? Or do they come that way stock?

[IanL]

I'd be surprised if you could get any more with a stock engine, but if you want to spend the money on the four runs, we could all be wiser as a result <p>Come to think of it, you really want to do five (one with the valves under ECU control), to get the full story.

[Macen]

So... anyone tried for a longer time? Is it worth the money?
Will the gas usage decrease if you have the VRIS set to other than the default setting? If it is so, then it could be interesting with a VRTuner.

[Talon_66]

I think it would be good for us ZE people running Curved Neck IMs because u can set the proper VRIS points.

[Sam Baker]

OOOH i've heard of this before.. a modded 626 with a klze had one! it's like a vtec controller right? i just heard the benefits of controlling the vris is that not only could you control *where it kicks in, but that you could have it kick in during the entire gear.. that would be sick! that means instant throttle response and hella power at all times (low end and high).. if this is truly what it does, i'm totally in for a GB or even just to buy that sh*t haha

[lakersfan1]

You can only get a VRTuner used. Otherwise, you've got to buy a pair of MSD window switches.

[ZEmadman]

we've got to get a group buy on this!

...too bad rpmtuners.com doesnt exist anymore

<small>[ October 03, 2004, 12:18 AM: Message edited by: ZEmadman ]</small>

[mdavis]

Good luck finding one. I'd pay good money...