Switchable exhaust valves from cockpit on standard exhaust

Bit of a pain running 2 sets of wires from the rear.
Could try one of my wireless remotes ?

http://www.ferrarichat.com/forum/ferrari-parts-collectibles/398632-ferrari-430-remote-control-exhaust-valve-system.html

 

Yes. It's easily done. However, interrupting the electrical connection with a switch rather than just disconnecting the vacuum pipe and plugging it will set error codes in the motronic units, so it's best avoided.

 

I've done this. You need one six pole switch. You use only four of the poles but what it means is that you don't "join" the two circuits.

I never paid any attention to which wire I interupted but now that you ask the question it would be better to cut the earth than the positive. I did blow a fuse when my wire got snagged by the handbrake cable once upon a time so I guess I definitely spliced into the live on one side or the other.

I used twin speaker wire and eased it through the engine access opening. It would be better done by following one of the main looms and trying to get it into whatever passage is used but I only did it on a temp basis and it's stayed there ever since. For what it's worth the switch generally stays in the "auto" mode but I do also have a rather loud rear box so might be inclined to leave open more frequently if I were using the OEM 'box.

I've never had any codes thrown on my car as a result of this.

 

Codes "thrown" and codes pending/stored are two different things...

 

None that light the CEL or register on my OBD. Maybe some spurious codes held in a deep dark place only an SD machine can read but certainly no ill effects.

 

The jury is still out in pro-circles. Back pressure changes on standard systems are an unknown quantity.

 

A few years ago a guy posted here about an extra switch on his new 360 console - it took a while to figure it out but he had an exhaust switch wired into the blank (on a US car) where the Euro has a foglight switch - it then turned out lots of people had done that or something similar - I'm sure full details are in that thread or others like it

 

valve control » Ferrari 360 » Ferrari » Car Models » Capristo ExhaustSystems

 

No pics handy I'm afraid but I used a small toggle switch not unlike this one....

Google Image Result for http://www.elecdirect.com/images/pageheaders/6terminaldpdt.jpg

I drilled a small hole in one of the two blank plates I have just behind the petrol cap / bonnet release buttons. Solder one pair of your speaker wires to the centre pole and either the forward or reverse poles on the same side and do the same with your second speaker wire. When the switch is in one position you are making a circuit between the two wires, when in the other position you're breaking it. Yes, I just went out the back of the centre console, under the carpet and through the inspection hatch, I brought both wires out on the one side and went across at the back of the car to pick up the solenoid on the opposite side. Select wire to cut and simply join the two ends of your broken solenoid wire to the two ends of your speaker wire. Repeat on other side. In on position the circuit is "made" and the valves operate as normal, in the other they stay open.

I respect Rusty's posts above but this hasn't caused my car any trouble whatsoever (save only when one of the wires got caught up in my handbrake which caused a short and blew a fuse.

Earth / Neutral / Negative - all the one buddy!

 

Also, if you are concerned about the possibility of codes being stored, another option would be to install a second solenoid valve in-line on each bypass valve (after the OEM one).

Something like this might be suitable.... Electric Solenoid 1/4 Brass Valve Air Water Gas 12v DC Volt NPT w/ 1/4 Hose Barb | eBay

With this you would eliminate any risk of causing your ECU any confusion as it would continue to open and close the OEM solenoid but you would control whether or not to allow the vacuum to reach the bybass valves with this separate valve. It would be just slightly more difficult to install but still only a small fraction of the quite ridiculously priced "kits" that are available.

 

The valves are powered by a two wire connector (one per valve) - one wire is permanent +12V, the other is Ground which is switched by the ECU.

If I was going to do this would insert a relay on each of the ground wires and use them to open and close the contact to the valve. That way there can't be any any issues with additional wiring connected to the car's loom.

 

Ding ding! We have a winner! Aldous is spot on. At least use a relay to stop unnecessary loading of the ground from the Motronic. You are running that earth point all the way from the motronic to the front of the car, through a switch and back again which is unwise, to say the least. The more expensive kits such as the Capristo offering are not just a switch. They won't generate an open circuit code. The cheap remote fob kits will open and close the valve, but consider this; have they been NVH tested? Are they water/heat proof? I fear not. Therefore, if one were to fail, the likely hood of a 12volt spike being transferred to an (unprotected) earth output of your motronic unit is high. The consequences of that don't need an explanation.

 

I have done exactly as you are attempting and have no problems using two relays. I have posted full details in the other Ferrari owner / enthusiasts forum ... Ferrari Life. Details include full electrical schematics on installing the relays and routing the wiring to the passenger cockpit. I used a "fog light" switch to install in the panel to the left of the steering wheel. I have been running with this setup for several weeks now and have absolutely no problems at all.

Unfortunately Ferrari Chat rules do not allow insertion of links to Ferrari Life ... a bit of jealously I guess.

Go to Ferrari Life forum and do a search on "Converting 430 Exhaust for 360" in the "Modern V8s" topic area.

Regards,

Steve

 

After giving this a bit of thought, I have come to the conclusion that there are significant issues in switching either the ground or the 12V wires to the solenoids.

If the ground wire is switched then, since it is connected directly to the ECU's, you risk damaging the Motronics if the wire is accidentally shorted to anything live.

If the 12V wire is switched then you need to be aware that there are other circuits directly connected to this wire without the protection of a fuse or diode. On a 360 these circuits are:

Variable Length Inlet Manifold Valves
Plenum Chamber Compensation Valve
Fuel Injectors
Lambda (Oxygen) Sensors
Mass Air Flow Meters (MAF)
Secondary Air Solenoid Valve (USA Only)

If the 12V wire is accidentally shorted to ground or if a current surge occurred then there is a real risk of damaging these other circuits/components.

Protection using good quality relays is the way forward.

 

Good points, Voicey. When I did mine, I installed the relays immediately adjascent to the vacuum solenoids that control the bypass valves. So the length of the my "switched" connection (I used the ground connection) is only about 3 or 4 cm so the risk of shorting to any live circuit is minimal.

Steve
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It's a long time since I did this switch so I'm vague as regards the detail and reasoning of my installation. Switching on the positive is safe. A short to ground blows a fuse and the circuit is protected. If you think about it, the OEM installation also has the potential to ground out accidentally and so it is already already suitably protected.

However, if one wanted to do this as safely as possible and with the minimum amount of intrusion the answer is surely to put a couple of additional 12 volt switchable valves on the pneumatic line. Power from a suitable source to a fuse to the switch to the valve. Disconnect OEM vacuum pipe from exhaust valve and connect to new valve and then run a new pipe from there to the exhaust valve. No cutting of original loom, completely separate from all electrics, completely reversible and safe.

That said, I'm happy with my solution, three years and counting.

 

Sounds good to me, I like the idea of having the best of both worlds... 👍

 

What is the default valve state? (no power, car off)
Are they open or closed?

 

The default valve state is valve open ... i.e., the exhaust has free flow from the cat to the exhaust tips, bypassing the muffler.

Car running below 4000 rpm or so, the ECU signals the bypass valve solenoids to close the valves and the state changes to closed, which forces all exhaust through the muffler. Above 4000 rpm or so, the ECU will open the valve. The actual parameters for opening the valves depend a bit on the programming in the ECU. E.g., the Stradale is different than the stock 360.

Regards,

Steve

 

Thanks Steve, what you posted (diagram) is the perfect $5 solution! Who ever heard of a Ferrari mod costing $5 ?? Love it! Great reason to keep the stock exhaust and just change the headers to Capristos.