DIY: ZL1 exhaust fuse bypass switch

[Mr. Wyndham]

...I'm afraid I couldn't think of a fancy name for this...

After spending the better part of 2500 miles with my car...I decided a whole lot of it was exactly what I wanted, and very little modifications were required...one of the few things I wanted to try, however, was the exhaust fuse pull.....but getting to that fuse box in the trunk was more annoying than I could have ever imagined....

So...that afternoon, I stopped at the auto parts store, picked up two electronic components and set to work bypassing the fuse so I'd never have to tear the trunk apart again!

~$12.00 in parts, and 2 hours worth of work later, and I can "fuse pull" without really doing it. Keep in mind this is just a "remote" fuse pull....and doesn't allow me to open/close the valves on a whim. This modification lets me keep the valves open at all times, or revert to factory operation.

There is no cutting/screwing to do this modification. I used a factory hole in the sheet metal.

Onto the DIY:

Parts from Advanced Auto:

1 - In-line 10A ATM fuse holder (10Ga)
1 - On/Off toggle switch (any on/off switch with a circular collar will work)

Other parts (laying around the house)

24" 12Ga wire
2 - male blade connectors
2 - barrel crimp connector
2 - 1/2" nylon washers
Soldering iron & solder/flux
Wire cutters
Black electrical tape



Step One:

- Remove the deck lid seal...just enough to pull the trim piece from the trunk up and out. Be careful, because there's some sticky sealant underneath that you don't want on your clothes...it is the consistency of dried-up vaseline.

- Remove the cargo net (if applicable), and unscrew the six retaining nuts/cargo net hooks.

- Grasp the trim piece from the lower corners and pull UP as well as inward slightly. It will pop out of place when the retaining clips (metal, they shouldn't break - but be gentle anyways) give way.





Step Two:

- Remove the screw-on carpet retainer from the bottom passenger-side of the trunk, and the push-style retainer from the upper portion of the carpet. The push retainer will be a royal pain to remove....just pull as hard as you can, I used pliers. It may become damaged when it finally gives....I was able to reuse mine, but you can find a replacement at your local auto-parts store.

-Fold the carpet towards the center of the trunk to expose the fuse box area.




Step Three:

- You'll need to place all the electrical components to judge how much of the 12Ga wire to cut. I admit, I didn't measure anything when doing this, I just estimated based on fit...

- Cut one roughly 6" long piece of 12Ga wire to join to fuse-box side of the in-line fuse holder. The standard 10Ga wire does not fit well between the cover of the fuse box and the holder.

- Cut the rest of your wires so you can have the return line (plugged into the other side of the fuse terminal), and an extension on the other end of the in-line fuse holder. These wires need to be roughly the same size, and able to run back to the toggle switch you'll have mounted to the hole in the sheet metal to the right of the speaker.

-Then join your wires using a barrel crimp connector. Tug with medium force to make sure the crimp is solid.




Step Four:

- Using a pair of wire-cutters, trim the blade connectors until they best mimic the width of the fuse prongs.

- Using the flat portion of the wire-cutters, pinch the edges of the now-trimmed blade connector to peen over the sharp, rough edges until you can run your finger smoothly over them.

-Crimp the connectors to the fuse-box side of the 12Ga wires.




Step Five:

- Dry-fit the incomplete harness. Once length has been confirmed, flux the switch and wires in preparation for soldering.

- I twisted and bent over the loose ends (the other ends should have the trimmed blade connectors) of the wire in the holes in the switches terminals.

- Solder these ends, ensuring the metal does not drip or otherwise short the two leads.

-After it's cooled, insulate the terminals with electrical tape. And continue winding the electrical tape down the wires (avoiding the fuse holder) to create a wiring harness.




Step Six:

-Install the F8 fuse into the fuse holder. It's recommended that you test resistance with a multimeter to ensure proper operation when switch is "On", and "Off".

- Using the nylon washers (remove the component-side collar from the switch), install the switch into the hole and tighten the threaded collar, being careful to avoid cross-threading/stripping the plastic threads.

- Feed the harness carefully downwards behind the existing wiring harness tied to the side of the trunk.

- Plug the trimmed blade connectors into the F8 "exhaust flapper" fuse. Double and Triple-check to make certain you are in the correct slots.

- Gently fold the wires to the rearward side of the fuse box and replace the fuse box cover. Push until it clicks into place. If there is resistance from the wires, troubleshoot the problem - Do Not force the cover closed.





Step Seven:

- Start the ZL1, and rev the engine to about 3000 rpms, letting it fall back to idle. When the switch is "ON", you should hear the metallic click of the exhaust valves as the tach drops past 1000 rpms. When the switch is "OFF", you should hear a noticeable difference in the low-rev sound when you blip the throttle, and no metallic click as the engine speed returns to idle.

- Replace the carpet, carpet retainers, trunk trim piece, cargo net retainers, and deck lid seal.

- Enjoy!

[JMAN311]

Awesome write-up. Thanks Dragoneye!

[mlee]

Nice alternative to M2W...

[Silverguardrail]

Nice job !

[DangerZL1]

This is a great write-up and I like the location you chose for the switch. I wouldn't want to route the wires into the interior either. I had problems with the same plug you did, but I was able to remove it with a trim plug removal tool.

[JoeP@TeamBeckyD]

Nice DIY....
Great job!

[Troyb]

That is awesome. I can't wait to get mine to do it. I will have to wait to break it in properly of course.

[Joebot8484]

Nice!

[Fat_Nick]

Very cool.

[radz28]

EXCELLENT DYI!!! KUDOS!!!

[hognutz]

any reason you did not bring the switch up driver accessable? I only ask because my plan is the same thing only bring the switch farther forward.

on vett's I have always though people were crazy for spending $100 on M2W but the fuse box is right up front. In this case I guess the one advantage is you will have have to run wires the lenght of the car.

[Camarowguy]

If you put a relay in the place of the switch, you could just run one wire up to the front to a switch do you can control it from the drivers seat.

[Mr. Wyndham]

Thanks for the compliments, guys!!

I was dying to do this fuse pull after a while.....and once I saw how much of a pain it was to access it....I HAD to do something to make it easier!

Originally Posted by hognutz

any reason you did not bring the switch up driver accessable? I only ask because my plan is the same thing only bring the switch farther forward.

on vett's I have always though people were crazy for spending $100 on M2W but the fuse box is right up front. In this case I guess the one advantage is you will have have to run wires the lenght of the car.

Originally Posted by Camarowguy

If you put a relay in the place of the switch, you could just run one wire up to the front to a switch do you can control it from the drivers seat.

I might be kind of a wiener for saying it....but I have absolutely zero intentions of pulling up the carpet, etc on the interior to run a wire for this. I just don't have the stomach for it. And I haven't felt the need to keep switching between "modes", yet...to where it would be much more convenient from the cabin...

It might just be me. In the future - I can definitely see myself installing something that allows me to control the exhaust via the home-link button...but this works very well for now.


On a related note....I didn't notice a HUGE difference in sound...obviously, there's more volume at lower revs...but idle doesn't change, nor does WOT above...~3000 rpms. Opening the valves also allows for a kind of annoying resonance (not drone) when accelerating in the overdrive gears. I've got to say, Camaro team did a tremendous job with this exhaust system, imo.

(Still...it's nice to have that extra volume when playing around. )

[DangerZL1]

Originally Posted by Troyb

That is awesome. I can't wait to get mine to do it. I will have to wait to break it in properly of course.

Troy, there's no need to break it in before installing the switch or Exhaust commander. It isn't used under full throttle, just above 1000 even in crusing around you get the enjoyment of a louder exhaust, if that's your thing. I've found that sometimes I want the extra volume, but other times not. Like Dragoneye said, you may come to appreciate how good the stock system is.