N/A tuning 20V, VVIS, something diffirent.

[razorx]

rozorx
Great write up. I have a quiestion. Were you able to retrofit the VVIS monifold on an engine that didn't have it before or did you simply over ride control on a car that already had it? In the US, Volvo put VVIS on 850s made in 93 and early 94. All cars that had 4 stud wheels. All 5 stud wheel cars don't have VVIS. I want to retrofit a VVIS manifold on my 96 850. Does it bolt up to the engine the same? Do you know if that is possible?
cheers
Justin

I built it on a late '93, so it had a VVIS inlet manifold.
I am not sure if the mountings are the same as for the newer manifolds without VVIS. If it fits, you will also need the solenoid. Check the vacuum diagrams. Exept vacuum hoses you will need a non return valve and a T coupling piece.

Regards,
Y.

[polskamafia mjl]

So essentially this is will have no effect on my 96 GLT

[drsugg]

Hello; First I must say,very interesting! I drive a 97 850 na 5 speed. I also happen to have a complete extra 850 motor with the VVIS manifold. I have been thinking of trying to install it on the 97, but knew it would need a stand alone controller. I know the VVIS can really affect engine performance from past and present applications of the concept. Let us know when we can procure one of your controllers.As far as it bolting on,they use the same manifold gasket and it looks to have all the usual attachments. The vacuum solenoid is also mounted on the manifold.

[tjts1]

As far as it bolting on,they use the same manifold gasket and it looks to have all the usual attachments. The vacuum solenoid is also mounted on the manifold.

Thats great! I'm going to pick up one of these next time I'm at the JY.

[razorx]

Nice these enthousiast reactions.
Saterday 28th of this month I hope to have performance data on paper.
Done by a company which can do partial load tests.

All the CAD/CAM work for the electronics is done.
I'll keep you informed about the results.

To keep a long story short , I want to come with complete data.
Kind regards,
Yits.

[t5rrr]

Very interesting! A+ for effort and brain cells put into this exercise.
Can't wait for the preliminary test results

*subscribed to thread

[razorx]

Good day everybody.
For me it was a very exiting day.
Finally a possibillity to do some partial load testing.
I had an appointment with a good tuning company that does some serious race tuning as well. So I did not had to explain that it will not emprove te maximum power but only the availability of power at low revs (below 4100rpm).
They have the equipment to do partial load testing, to compensate for transmission losses, e.t.c..

Ok enough talking lets go to the graphs.
The first graph is with 30% throttle opening.
The red diagram is the resulte of the original Volvo VVIS system.
The blue one is the result of my controller.


Now a test with 50% throttle opening.
The blue one is the original Volvo one
The red one is the result of my system.


So at non full throttle opening a power increase of approximately 9bhp, and a torque increase of 20Nm.
This increase is probably, not completely tested yet, availibe till about 75% throttle openingeg

I am very happy with the results. Of course I felt the difference, but finally I have it in hard numbers. AFR no worry by the way. Still OK.

Conclusion: On partial load about 9hp increase and 20Nm,
Quite happy.

Over here it is midnight, so I wish you a nice sleep

Kind regards,
Yits.

And Yes, I would like to sell this. But I dont know the forum rules.
Simply said, I havent read them yet. I will do and contact Matthew.

P.S. Thanks to FastTech for all the time!

[tjts1]

Very cool. Thanks for posting this. I really need to look into swapping the VVIS manifold on my 96.

[razorx]

Thank you.

I am very happy with the results of the tests (previous posts).

I have noticed that with this analog approach. Next to an inprovement of 9hp and 20Nm under partial load (just where you need it), there is also an inprovement during accelleration. It seems not a lot, but concidering what the car is giving you at partial load, it is a serouous improvement.

An other thing:
During heavy accelleration (with my mod), the air runs at high speed, only small long inlet channel open, high speed of mixture. As soon as the second short inlet channel opens, the fast incoming mixture forces the mixture of the just opened channel to get the same speed.

This was not behaveour by design. Just a little extra.
During testing with various variants we noticed the following:
-AT behaveour, less nervous
-20V 2.0 Engines, Italian models, finally a nice drivable car.

Cars running on LPG
-OMVL milennium, system: Same increase
-Vialle liquid injection system (best LPG system ever) the same
-Vialle, how do you name this in English, evaporating system: a gain, but not as it should be.

I am very glad to have data on paper.
20Nm and 9bhp reletively cheap.
So it is possible to do some N/A tuning.

So N/A tuning is possible without spending a fortune.
Don't expect miracles, but this is a serious improvement.
Kind regards,
Y.

Please feel free to Pm for more information

[renns]

Very nice work! I wonder why Volvo chose to configure the system in the way they did?

What is the normal state of the VVIS valve? If it's normally in the closed position, I suppose one could test the low-speed improvement by simply unplugging the actuator?

Did you happen to log air-fuel ratio for the runs you posted earlier? Does the stock ecu correct automatically for changes in the changes in volumetric efficiency?