How to BiModal exhaust

[monstar]

Hey Monstar,

Do you mind posting links on what I need to buy to get this up and running? Do I need to cut or solder any wires? I hope not because electrical wiring and me don't mix and never ends well

Sure, replace "NPP" with "HSV Bimodal":

The instructions are here. Most of that stuff is about routing the vacuum hose from back of engine to the rear of a corvette, which doesn't apply.
All you need do is run the vacuum line from the engine to the rear diffuser on the drivers side of the car and follow two important rules,
1. 100% make the line is away from any exhaust components.
2. Make sure when you secure the line but do not over tighten the tie wraps and crush the line or you don’t kink the line, both restrict the vacuum flow. The best place to run the line is on top of the tunnel plate, use a wire snake or a metal coat hanger to snake the line through the tunnel.
Undo the scrivets holding up the rear diffuser in place and tuck the control box up there.
Connect the vacuum hose.
Connect the muffler hose (which has a t-piece to each side) to each spigot on the diaphragm actuator of each muffler.
Run the power wire up near the spare wheel well and through one of the rubber grommets (mine is sportwagon so prollly different).
Zip up the diffuser neatly by replacing the scrivets.
Run the power line under the trim to the battery compartment, choose a fuse to piggy back on and plug it in.
Voila.

 

[v-petn]

Awesome thanks Monster I'll look into this

 

[v-petn]

Hey Monstar when you get a chance can you take a photo of which vacuum you connected to from engine? Also which fuse did you piggy back off?

Also does it matter which model hsv bimodal as I've seen a few different models

 

[monstar]

Hey Monstar when you get a chance can you take a photo of which vacuum you connected to from engine? Also which fuse did you piggy back off?

Also does it matter which model hsv bimodal as I've seen a few different models

Regarding which fuse it was on the left, bottom one I think. Check amperage and instructions provided with unit.
It has to be the vacuum operated original style, and not the ute / long wheel base ones that have an extension on the tips. Else you need to trim that off. So HSV E3 sedan bimodal.

 

[v-petn]

Thanks Monstar

 

[Xplaya]

The main thing here is the bit before the catback, properly sized and tuned section between headers and catback (3" rising to 4" megaphone diffuser).

Can you explain this a little more or post links what this is? I have never heard of a megaphone diffuser before, what does it do? And does that mean you have no cats?

 

[monstar]

Can you explain this a little more or post links what this is? I have never heard of a megaphone diffuser before, what does it do? And does that mean you have no cats?

Yes, is basically a type of tuned secondary collector that promotes exhaust flow from the header primaries.
You still retain cats, the design features use of retained heat in the cat substrate at running temps to propel gasses out of the tuned expansion chamber.

 

[VE Mik]

Guys,
I bought a set of vf bimodal electric valve mufflers and fitted them to my Ve series 2 calais. They seriously are the best exhaust mod I have done. Fully open they have a nice mild sound. I have sourced an remote electric kit complete with remote and cutout valves that I am going to get an exhaust shop to cut off the original ones and replace them with the new ones. Then I will have a bimodal system. Easy.

 

[monstar]

Guys,
I bought a set of vf bimodal electric valve mufflers and fitted them to my Ve series 2 calais. They seriously are the best exhaust mod I have done. Fully open they have a nice mild sound. I have sourced an remote electric kit complete with remote and cutout valves that I am going to get an exhaust shop to cut off the original ones and replace them with the new ones. Then I will have a bimodal system. Easy.

Keen to hear that! DO you have a link for the remote electric kit?

 

[VE Mik]

Keen to hear that! DO you have a link for the remote electric kit?

Hi mate,
You buy the kit on eBay from wild industries. Comes with 2 electric valves, control box and remotes. Easy as install. Just cut out the originals and weld these guys on. Connect wiring and all done. Instant bimodal.