Electronic Bi-Modal Valves

[stooge]

yeah they still work fine, it will sound better once I find a better mid section or I get this center muffler delete welded in

the afm sounds like ass but that's something to tackle another day.

the only thing I had a problem with the bi modal mod was the wire I ran to the switch did not have very good shielding on it so sometimes the valves would change state so I just put a relay down the back in the box and had the switch trigger the relay.
I could not be bothered re running a new wire so it was the quickest fix lol but if you use wire with decent shielding it should be fine.

the better way would still be to build the pwm circuit but finding that information will be hard because most people look to profit off things like that instead of sharing the info.
there is one thread where a guy that has built a circuit he is selling but he also shared all the information involved(awesome guy imo)
https://www.corvetteforum.com/forum...full-open-close-non-factory-npp-retrofit.html

it is complicated though and it can be simplified using Arduino, oneday I will find myself near a wrecker in perth and snag a few more controllers then I will take a stab at building the pwm circuit but for now my hacked up set work perfect.

 

[Tripxit]

I've looked over posts regarding pwm but it just looks like a lot of work and I can't see any advantage over what you have come up with (for what I want, simple on/off). I may be wrong but your solution only uses power for short periods to open and close the valve (spring disconnected) whereas the pwm option uses voltage to hold the valve closed and springs back when no voltage.

Just picked up a HSV E3 mid section to go with the bi modals. Hopefully it'll sound good.

 

[Mattricho]

Here's a link to my series 1 SSV with a GEN F mid section and series 2 bimodels.

Im also looking for a set of 340kw headers aswell but im thinking about a set of 4-1 headers instead of the HSV ones

I also got the bimodels working by changing the bimodel valve and motors for some i got off eBay there's a write up in another bimodel thread on here

 

[stooge]

I may be wrong but your solution only uses power for short periods to open and close the valve (spring disconnected) whereas the pwm option uses voltage to hold the valve closed and springs back when no voltage.

Yes that is correct, the way i set mine up is to just pulse the motor for about 800ms with 12v to change the valve state and unhook/disable the spring so the valve remains closed while the vehicle is off.

I did experiment with making a full pwm or stepper circuit with arduino but i found when i started the vheicle the fluctuation in voltage from starting caused the motors to move to a random position so it was an instance where "keep it simple stupid"(KISS) was required.

For around $40 it did what i wanted so i am happy enough.

 

[Tripxit]

Here's a link to my series 1 SSV with a GEN F mid section and series 2 bimodels.

Im also looking for a set of 340kw headers aswell but im thinking about a set of 4-1 headers instead of the HSV ones

I also got the bimodels working by changing the bimodel valve and motors for some i got off eBay there's a write up in another bimodel thread on here

Sounds great. 340kw headers with aftermarket cats or Pacemakers was going to be my next purchase. Will see how the mid section will go first. Did you have to weld in bungs for the o2 sensors on the gen F exhaust? Ones I looked at didn't have them so settled for the E3.

Did you use a bi-modal vacuum valve off a hsv?

Is that Avalon Rd near Brisbane you were driving on?

 

[Tripxit]

For around $40 it did what i wanted so i am happy enough.

Yeah price is good. Just purchased the bits from Jaycar today.

 

[Mattricho]

@Tripxit
Yer I had a local exhaust shop weld in some new O2 bungs.

I honestly don’t remember where I shot that video as it was like 7-8 months ago lol

Here’s the link to thread of what I did with the bimodels (post #5)

https://forums.justcommodores.com.a...bimodal-exhaust-on-vf-s1.272536/#post-2985199

 

[TimjamisonSSV]

HEY GUYS AND GIRLS HAS ANYONE COME UP WITH A SIMPLY PLUG IN WIRING SCHEMATICS TO JUST HAVE THE VALVE OPEN OR CLOSED??

 

[John Revill]

HEY GUYS AND GIRLS HAS ANYONE COME UP WITH A SIMPLY PLUG IN WIRING SCHEMATICS TO JUST HAVE THE VALVE OPEN OR CLOSED??

Unfortunately it's not that simple. The values have 3 wires. +12V, GND, and a signal wire. The signal wire is not a simple power on, no power off setup. It is a +10V 200Hz PWM signal with 20% duty cycle for off and 80% duty cycle for on. Why that made it this complicated I have no idea. I have been working on a wireless control for a few months now, but there as been a cost blow out and mass producing them.

https://forums.justcommodores.com.au/threads/vf-bimodal-pin-diagram.256454/page-3

 

[TimjamisonSSV]

What sort of cost are we talking??