Mach5 downpipe and SS exhaust review

[lynchy73]

Top 3 are valve controller related

Hm yea I’m having a really hard time understanding how your shop did the wiring. The original wiring is a 4 pin connector, I’m assuming that’s still plugged into the OEM valve controller and tucked somewhere hidden? Then I’m assuming they added a 12 volt source to the Mach 5 box and connected the 2 pin wire supplied by Mach 5 to the Mach 5 valve controller on the exhaust so you can at least control open and close but probably no “auto” functionality. Is that right?

The OEM exhaust valve is directly connected to the OEM valve connector, which is why it’s in the middle under the rear plate, rather than off to the left as it should be.

That 3 way cable is now directly connecting the M5 box to a 12V supply, the other 2 connections (valve extension cable) are gone.

Yes, no Auto function. I’m guessing the OEM valve is also not functioning, hence the errors.

Thinking back, when my exhaust valve previously needed calibration, I was able to clear the code, but the error would appear again after a drive. These errors can’t be cleared. The car also felt noticeably low on power when I tested it.

 

[lynchy73]

Also here’s a picture of the fuse, it’s the 5 amp one between the 7.5 and 15 amp one. The lotus Emira handbook labels these positions very confusingly as they include both v6 and i4 so some of the positions listed in the manual is off

The fuse information is in the handbook…. didn’t think to check it. Just had a look and yeah it’s there

I couldn’t for the life of me find that info in the service manual.

 

[lynchy73]

@Milk242 the fuse was blown (thanks again)and the cable has been located

Next to get it working properly and hopefully get some of the errors cleared

 

[Milk242]

@Milk242 the fuse was blown (thanks again)and the cable has been located

Next to get it working properly and hopefully get some of the errors cleared

Awesome that you figured out the fuse.
And lol that they turned the 3 way cable into an extension cable for the OEM valve controller.

I would just use the OEM valve controller at this point and put a heat shield around that cable and get a milltek or ask BG for their valve controller.

 

[675430VME]

Awesome that you figured out the fuse.
And lol that they turned the 3 way cable into an extension cable for the OEM valve controller.

I would just use the OEM valve controller at this point and put a heat shield around that cable and get a milltek or ask BG for their valve controller.

Unfortunately BG's valve controller can only been used on BG's exhaust.

 

[lynchy73]

Awesome that you figured out the fuse.
And lol that they turned the 3 way cable into an extension cable for the OEM valve controller.

I would just use the OEM valve controller at this point and put a heat shield around that cable and get a milltek or ask BG for their valve controller.

Sorry, I don’t understand your suggestion. Why wouldn’t I just get the Mach5 valve controller working as intended with my Mach5 exhaust?

 

[Milk242]

Sorry, I don’t understand your suggestion. Why wouldn’t I just get the Mach5 valve controller working as intended with my Mach5 exhaust?

Oh, I wasn’t sure if the butchered cable was fixable, if it is, then go ahead.

 

[Andrew25]

Finally got the Mach5 downpipe and stainless steel exhaust installed, plus their valve controller.

Overall, super happy with it. The sound is awesome—nice deep rumble. In Sport or Track, you get some drone in the lower gears on the highway, but once you’re in the higher gears it goes away. Inside, it kind of sounds like the fake i4 noise, except this time it’s actually real since I unplugged the wire. No clue what it sounds like outside other than idle and a few revs in the driveway.

As for CELs: none caused by the downpipe. I did cause one myself when installing the valve controller because I plugged the wires in wrong (they come without connectors so you can route them through the trunk). That ended up blowing the exhaust valve fuse in the fuse box behind the left seat, which took way too long to track down. Replaced the fuse, wired everything correctly, did a couple start cycles, and the CEL went away.

Only extra thing I added was a silicone-coated fiberglass heat sleeve for the valve controller wires (basically like the OEM shielding) because my wire routing felt a little too close to the exhaust.

All in all, the exhaust sounds great, no downpipe related CELs, and the valve controller moves the OEM unit away from the exhaust so you’re less likely to end up in limp mode if the OEM controller ever melts.

Edit:
Forgot to mention that the crackles is now really pronounced in sport and track mode when coming to a stop rapidly and the car is downshifting through the gears

Can you share a video of the sound of your setup? If I understood you correctly, you did not decat your system, right?

 

[675430VME]

Can you share a video of the sound of your setup? If I understood you correctly, you did not decat your system, right?

No, he has a 200 cat downpipe from Mach5.

 

[lynchy73]

Oh, I wasn’t sure if the butchered cable was fixable, if it is, then go ahead.

I’m pretty sure it can be patched up and if not I’ll get a replacement cable.

I do wonder how they can determine the OEM valve position (for Auto function) when the M5 controller only appears to have access to the 12V supply for the OEM valve motor

 

[Milk242]

I’m pretty sure it can be patched up and if not I’ll get a replacement cable.

I do wonder how they can determine the OEM valve position (for Auto function) when the M5 controller only appears to have access to the 12V supply for the OEM valve motor

Hm good question, I just assumed auto worked as it’s pretty quiet in tour mode.

Anyways, I ordered the milltek v2 controller during Black Friday event and plan to install that when it gets in because I wasn’t a fan of the Mach5 wiring coming into the trunk using the holes for the carpet liner retaining clips. The carpet now sits uneven because of the wiring.

 

[lynchy73]

Hm good question, I just assumed auto worked as it’s pretty quiet in tour mode.

Anyways, I ordered the milltek v2 controller during Black Friday event and plan to install that when it gets in because I wasn’t a fan of the Mach5 wiring coming into the trunk using the holes for the carpet liner retaining clips. The carpet now sits uneven because of the wiring.

I’m sure Auto mode does work, just not sure how they know the position Of the OEM valve. I want that function, as TBH the car is kind of anti social with the exhaust valve open.

You can run the cables differently into the trunk, not through the holes for the carpet clips. I’ll get some pics if you’re interested, showing how it was routed?

I do think this concept of putting the factory valve on a fake plate is a good one. My OEM valve has signs of melting and the exhaust valve (on my old Ti exhaust with my OEM valve) was no longer closing properly after I’d done a single session on track (could hear the valve rattling when closed).

 

[Milk242]

I’m sure Auto mode does work, just not sure how they know the position Of the OEM valve. I want that function, as TBH the car is kind of anti social with the exhaust valve open.

You can run the cables differently into the trunk, not through the holes for the carpet clips. I’ll get some pics if you’re interested, showing how it was routed?

I do think this concept of putting the factory valve on a fake plate is a good one. My OEM valve has signs of melting and the exhaust valve (on my old Ti exhaust with my OEM valve) was no longer closing properly after I’d done a single session on track (could hear the valve rattling when closed).

Yea that would be awesome if you can show me how you still were able to route it into the trunk.

 

[Milk242]

I’m sure Auto mode does work, just not sure how they know the position Of the OEM valve. I want that function, as TBH the car is kind of anti social with the exhaust valve open.

You can run the cables differently into the trunk, not through the holes for the carpet clips. I’ll get some pics if you’re interested, showing how it was routed?

I do think this concept of putting the factory valve on a fake plate is a good one. My OEM valve has signs of melting and the exhaust valve (on my old Ti exhaust with my OEM valve) was no longer closing properly after I’d done a single session on track (could hear the valve rattling when closed).

Just asked mach5, they don’t have auto mode