Hooking up TVIS - rpm or vac based?

[cat007]

Hey all,

I'm going to attempt to hook up TVIS on my 1G-GTE as I disconnected it since switching to the Stinger ECU.

The ECU can control the little solenoid - but my question is - how should I activate it?

Should it be RPM activated, or vacuum/boost activated?

Or should I just use a toggle switch and test various ways?

Cheers

Hunt

[mjrstar]

i suggest rpm as you'll be needing the extra airflow above a certain rpm, whereas if it was boost switched and you were at light throttle and hi rpm you'd have the butterflies closed.

[cat007]

What about this - you can set it so its activated when below a certain RPM AND a certain boost.......

http://www.supras.co.nz/pics/ecu/relay.jpg

[loose_unit]

Rpm only based would be best and easiest. Ideally you would want to do dyno runs of each closed and open and then have it switch at the point where it intersects.

[cat007]

Rpm only based would be best and easiest. Ideally you would want to do dyno runs of each closed and open and then have it switch at the point where it intersects.

yeah I guess you're right.

I'll hook it up this week and have a play - although I'm going to be taking the gearbox off and rebuilding that - so maybe I'll wait

[loose_unit]

I had my acis switching with an air con solenoid and just triggered it with the rpm switch on the link. Easy to adjust and worked a treat.

[cat007]

I had my acis switching with an air con solenoid and just triggered it with the rpm switch on the link. Easy to adjust and worked a treat.

acis?

[xsspeed]

Similar but different to tvis

[loose_unit]

Has the same solenoid setup anyway so switches in the same way. has 2 different length runners instead.

[cat007]

OK help - I'm confused.
How the bloody hell does this stuff get hooked up.

A is open when there's no power to the solenoid and goes to C
B is closed until you put power on the solenoid and then it goes to A but never goes to C
I can suck through E but cant blow through it - and of course the opposite goes for D

I think D and C link together, as in the picture. Which would mean E goes to the actuator diaphram thing on the manifold. But then does that mean I put A or B to the vacuum part of the manifold?

arrrghhhh - silly inventions that are so simple yet I can figure out LOL

[QikStarlie]

from what i can figure:


a goes to tvis actuator
b can leave this open or plumb it back air intake. it vents air and lets butterflys open
c as connected.
d as connected.
e - vac reso intlet. to inlet manifold. has 1 way valve built in so stores vac.


use your rpm swich from ecu to put power onto the solenoid at desired rpm you'd like them to open....


ive only worked with acis not tvis. but if the butterflys are nomaly open (correct?) when nothing is connected. the above should work.

[cat007]

Thanks for that - I found this:

http://www.turbomr2.com/MR2/Reference/TVIS/TVIS.htm

Very good write up. I've set it so its on below 4200rpm, and off when above....

Will do testing tomorrow and data logging with it on and with it off - should be quite informative - even if I'm the only one that cares hehe

[cat007]

OK so I hooked it up - set it to be on below 4200rpm and did some before and after trial runs. Here's the results.

The ECU logs 10 times every second - so the "readings" are every time the ECU logs data (i.e. 10 times a second)

Without TVIS
Reading: 205 = 2003rpm @ 0.43PSI
Reading: 479 = 4225rpm @ 7.46PSI

With TVIS
Reading: 161 = 2098rpm @ 0.43PSI
Reading: 381 = 4234rpm @ 7.83PSI

So - I managed to gain 0.4PSI from just having TVIS on.

It may not sound like much - but bare in mind, both tests were done with the car at the same temp and on the same stretch of road (up a hill of course). And if you work out, the difference without TVIS took 274 readings (27.4 seconds) to get from basically 2000rpm to 4200rpm but with TVIS it only took 220 readings (22 seconds).

Thought someone on here might find all this interesting

[pc]

What do you mean when you say TVIS is 'on'?
normally the TVIS butterflies would be closed in the rev range from 2000rpm to 4200rpm... and TVIS would be 'on' (butterflies open) above 4200rpm.

[cat007]

What do you mean when you say TVIS is 'on'?
normally the TVIS butterflies would be closed in the rev range from 2000rpm to 4200rpm... and TVIS would be 'on' (butterflies open) above 4200rpm.

No normally the butterflies are open - TVIS closes them up until 4200rpm, then releases the vacuum thus opening the butterflies. The diaphram makes the system a N/O arrangement.

So when I say, TVIS is 'on' I mean that the I had set the ECU to close the butterflies before 4200rpm....