Mach5 downpipe and SS exhaust review

[Milk242]

Sounds like way too much trouble or potential trouble for a set and forget type of owner like me that just wants a bit more sound. Who makes a good sounding GPF back exhaust that does the trick without any risk of throwing codes or touching any of the emissions sensors?

The muffler portion doesn’t really improve the sound. The down pipe does all the work and so far proven that the Mach 5 one does not throw codes. The muffler portion you can just keep using your OEM valve controller. You can also get their straight pipe exhaust that others have talked about in other posts and not have to deal with their valve controller.

 

[Yukoncole]

The muffler portion doesn’t really improve the sound. The down pipe does all the work and so far proven that the Mach 5 one does not throw codes. The muffler portion you can just keep using your OEM valve controller. You can also get their straight pipe exhaust that others have talked about in other posts and not have to deal with their valve controller.

If you were to get the Mach5 Downpipe and the straight-pipe exhaust, what would you do with the factory valve controller? Does it toss codes to just set it aside? At least, that's what I assume you do. My track was adding the Miltek Controller and a Mach5 downpipe....would this solution work trouble-free?

 

[Milk242]

If you were to get the Mach5 Downpipe and the straight-pipe exhaust, what would you do with the factory valve controller? Does it toss codes to just set it aside? At least, that's what I assume you do. My track was adding the Miltek Controller and a Mach5 downpipe....would this solution work trouble-free?

They provide a relocation kit, it’s just a bracket that mounts the original valve motor and an 4 wire extension cable for the factory wiring to reach the new location.

The issue is with their non straight pipe exhaust valve motor setup. The valve controller and wiring is just not good. They provide a 2 position valve motor for the new exhaust and a relocation kit for the OEM one but luckily you can still use your OEM valve motor with this setup and forgo their valve controller and motor but I would pair it with a milltek valve controller

 

[lynchy73]

They provide a relocation kit, it’s just a bracket that mounts the original valve motor and an 4 wire extension cable for the factory wiring to reach the new location.

The issue is with their non straight pipe exhaust valve motor setup. The valve controller and wiring is just not good. They provide a 2 position valve motor for the new exhaust and a relocation kit for the OEM one but luckily you can still use your OEM valve motor with this setup and forgo their valve controller and motor but I would pair it with a milltek valve controller

I think Most of the issues I had were down to the low grade cable they used (2 core cable feeding the aftermarket valves was melted and shorted together near the valve). If they had used a proper high temperature cable with additional insulation, I’m sure it would’ve been fine. I’ve now gone with their straight through exhaust and it’s been problem free so far. I think it sounds a bit better than their valved exhaust and it’s lighter. No option to make it quieter with a remote though

 

[Yukoncole]

Most of the issues I had were down to the low grade cable they used. If they had used a proper high temperature cable with additional insulation, I’m sure it would’ve been fine. I’ve now gone with their strait through exhaust and it’s been problem free so far. I think it sounds a bit better than their valved exhaust and it’s lighter.

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Would love to hear sound clips if you have any; I am looking for a modest improvement over stock. I would prefer more, but my better half prefers to keep it non-abnoxious lol. My other fear with being at only 1000 miles is warranty void, which is what changing the downpipe would obviously do.

 

[lynchy73]

Would love to hear sound clips if you have any; I am looking for a modest improvement over stock. I would prefer more, but my better half prefers to keep it non-abnoxious lol. My other fear with being at only 1000 miles is warranty void, which is what changing the downpipe would obviously do.

Honestly, it’s borderline obnoxious with the straight pipe. I do have an Aerie sports cat fitted too, which makes some difference over the stock cat. Also have a decat and that was louder again. Will try to get some clips when I get a chance. My car is at the shop/track.

Don’t see how they could void your warranty with a cat and an exhaust.

 

[Yukoncole]

Honestly, it’s borderline obnoxious with the straight pipe. I do have an Aerie sports cat fitted too, which makes some difference over the stock cat. Also have a decat and that was louder again. Will try to get some clips when I get a chance. My car is at the shop/track.

Don’t see how they could void your warranty with a cat and an exhaust.

I thought I read somewhere that modifying the downpipe was a warranty violation, maybe I am imagining that.

 

[lynchy73]

I thought I read somewhere that modifying the downpipe was a warranty violation, maybe I am imagining that.

You might be right, I don’t actually know, but in my mind an exhaust swap doesn’t seem like grounds for voiding your warranty, other than for related parts of the car. Can ask the dealer if it’s ok to do an exhaust.

 

[Yukoncole]

You might be right, I don’t actually know, but in my mind an exhaust swap doesn’t seem like grounds for voiding your warranty, other than for related parts of the car. Can ask the dealer if it’s ok to do an exhaust.

Yes, they can, or likely would, void anything related to the exhaust, and this can extend to the engine, as you are changing back-pressure and OEM-designed performance load.

 

[Kaz]

I thought I read somewhere that modifying the downpipe was a warranty violation, maybe I am imagining that.

This is completely dependent on your dealer and their relationship with Lotus, how they report individual cars to Lotus, and your relationship with your service department. In the States the service rep inputs parts and service and warranty requests that have to get approved by Lotus UK. Let's say you have an issue that is drivetrain related like a turbo failure, intercooler crack, etc and you have an aftermarket exhaust. Your service rep can choose to note on the warranty request that you have X Y Z parts on the car or they might not. That is a local issue as they all follow different protocols from what Lotus is asking.

Long story short it just depends how extreme your case is and what the issues are. I wouldn't sweat the small stuff like an exhaust - I mean I just assume I can be ready to replace the whole drivetrain if I need to but that's just me, everyone has their level of comfort. From current experience Galpin in LA is extremely pro-mod they certainly are not the mod nannies, but your dealer might be.

 

[Yukoncole]

This is completely dependent on your dealer and their relationship with Lotus, how they report individual cars to Lotus, and your relationship with your service department. In the States the service rep inputs parts and service and warranty requests that have to get approved by Lotus UK. Let's say you have an issue that is drivetrain related like a turbo failure, intercooler crack, etc and you have an aftermarket exhaust. Your service rep can choose to note on the warranty request that you have X Y Z parts on the car or they might not. That is a local issue as they all follow different protocols from what Lotus is asking.

Long story short it just depends how extreme your case is and what the issues are. I wouldn't sweat the small stuff like an exhaust - I mean I just assume I can be ready to replace the whole drivetrain if I need to but that's just me, everyone has their level of comfort. From current experience Galpin in LA is extremely pro-mod they certainly are not the mod nannies, but your dealer might be.

Thanks, Kaz! That makes a lot of sense. Now, just figure out my guy a bit more at Lotus of Orange County. He seems like the opposite of your guy; he was flipping out about the idea of the Milltek Valve Controller, even... saying he has seen multiple issues with them being closed, which caused engine failure...I have never seen anything like that mentioned anywhere, but I guess if one were to close it and then start beating on it.... backpressure could be a potential issue!

 

[F1 SML8R]

Thanks, Kaz! That makes a lot of sense. Now, just figure out my guy a bit more at Lotus of Orange County. He seems like the opposite of your guy; he was flipping out about the idea of the Milltek Valve Controller, even... saying he has seen multiple issues with them being closed, which caused engine failure...I have never seen anything like that mentioned anywhere, but I guess if one were to close it and then start beating on it.... backpressure could be a potential issue!

Your first problem is "Lotus of Orange County". Let's be frank here, that's not a Lotus dealership as much as it is a "used car dealership". I wouldn't hold my breath on having them ever be your advocate on anything "grey".

 

[Milk242]

Your first problem is "Lotus of Orange County". Let's be frank here, that's not a Lotus dealership as much as it is a "used car dealership". I wouldn't hold my breath on having them ever be your advocate on anything "grey".

Yea lotus rollout of dealerships in the US was pretty shitty but I understand franchisees don’t really want to take a chance on a niche brand in the US. I’m hoping geely will swing some of their weight and offer incentives and/or try to force Volvo franchisees to also co-brand as lotus dealerships once they get more than one vehicle offering in the US

 

[F1 SML8R]

I’m hoping geely will swing some of their weight and offer incentives and/or try to force Volvo franchisees to also co-brand as lotus dealerships once they get more than one vehicle offering in the US

Talk about polar opposites, but this might actually work to their advantage. Buy the "family car" and by the "cool car" at the same time. Service them at the same shop as well.

 

[Milk242]

Talk about polar opposites, but this might actually work to their advantage. Buy the "family car" and by the "cool car" at the same time. Service them at the same shop as well.

Family car electric/hybrid from Volvo, full electric performance from polestar and hybrid/gas sport performance from lotus. It could work hah

 

[Yukoncole]

Your first problem is "Lotus of Orange County". Let's be frank here, that's not a Lotus dealership as much as it is a "used car dealership". I wouldn't hold my breath on having them ever be your advocate on anything "grey".

Yeah, well, those "used cars" all sell for at least double the price, if not 10-plus times the price of our new cars! The Lotus is the peasant car there!

 

[Kaz]

I thought I'd post some video samples...taken with my phone so the mic and sounds are very subpar. And try and listen with headphones if you can. What is not coming across is the volume and impact of the sound, hard to capture on a phone - it's just way louder than whatever you are listening to when you watch these shrots. It's just my Lotus tech driving the car to hear what it sounds like from the outside. It's probably the best this I4 system will sound like in the platform. I am running an Aerie sports cat/downpipe with the Mach5 straight pipe race exhaust. I tried recording inside the car while driving using Meta glasses but the sound is clipping the volume on full throttle is clipping the mics...will try on a GoPro with actual mics.

 

[675430VME]

I thought I'd post some video samples...taken with my phone so the mic and sounds are very subpar. And try and listen with headphones if you can. What is not coming across is the volume and impact of the sound, hard to capture on a phone - it's just way louder than whatever you are listening to when you watch these shrots. It's just my Lotus tech driving the car to hear what it sounds like from the outside. It's probably the best this I4 system will sound like in the platform. I am running an Aerie sports cat/downpipe with the Mach5 straight pipe race exhaust. I tried recording inside the car while driving using Meta glasses but the sound is clipping the volume on full throttle is clipping the mics...will try on a GoPro with actual mics.

Wait until you do a de-cat for the i4!

 

[lynchy73]

Wait until you do a de-cat for the i4!

I did, It’s LOUD, especially with that burble tune.

Sports cat plus straight pipe is borderline obnoxious. Decat moves the needle to straight up obnoxious

I’m running the sports cat for now, it’s nice to be able to swap to factory ECU when needed and not get a CEL. Will have another play with the decat soon

 

[675430VME]

I did, It’s LOUD, especially with that burble tune.

Sports cat plus straight pipe is borderline obnoxious. Decat moves the needle to straight up obnoxious

I’m running the sports cat for now, it’s nice to be able to swap to factory ECU when needed and not get a CEL. Will have another play with the decat soon

But throttle response with decat is so much better than sports cat