Where did you purchase yours?

 

It’s been two years since I had a 400 for a loaner car in Dubai while my S was serviced . . . but that was my recollection as well. When I got my Federal 400 I thought the exhaust note was more subdued. But then I started doubting my recall, because it does still sound good. How much of a hassle is it to install?

 

@1swift1 - you can get it through your local dealer, or through LotusGarage.com. It's just over $100.
@ByJoveByJingle - i thought the car sounded OK from the factory, but with the decat it's jaw-droppingly good. On the install, I had my local Lotus specialist install it. They reported that they had to weld on a small extension to the decat pipe and open up the pipe slightly to get it to mate with the exhaust, but other than that relatively straightforward. 100% reversible in any case, and the decat pipe itself is only $100.

 

I just put in an order. I also ordered the clamp which is wider, this should fit right in without any welds.


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USA gets a different downpipe to go with our cat, which isn't immediately apparent when looking at the parts diagram. Plan on needing to weld up an extension.

 

Very interesting! Elitex - please keep us updated on the install when you get everything.

Anyone know how much weight it might save?

 

How does the sound compare to the non-decat car with the "engine protection valve" open (which I think is the default for sport and race modes, or you can just push the dash button in standard)?

 

@Dylan - no exaggeration, a huge difference. With the stock secondary cat, the car only sounded good to me hard on the throttle about 4K, but even still seemed a bit tame/neutered. With the decat pipe, it sounds good between idle and 4K, and unreal 4K-redline. Hard to describe the change in tone at 4K, but i'd say it's a throaty roar, somewhat similar to my friend's Ferrari 355.

I'd say it's about 2x the volume across the range, with a couple of pops here and there on throttle release/coasting, whereas the stock setup i never heard any pops.

 

Thanks for this great bit of info which I will file away for my future 400/410/430 ownership. Is it now similar to an S1 with a Plack exhaust installed?

 

Is there an O2 sensor downstream from the 2nd catalyser?

 

No. The O2 sensors are immediately pre and post the primary cats (which are integrated into the exhaust manifolds/headers). The 2nd cat (which is replaced by this pipe) has no effect on the O2 sensors as both are upstream of the 2nd cat.

 

This is very exciting. Coming from an E92 M3, I have been happy with the Evora's exhaust sound but not blown away (it is worlds better than the new F8X gen M3 which is one of the worst sounding cars I have ever heard IMHO). I do really love the Lotus option to keep things quieter for my neighbors when I am leaving for work early in the AM and to open up the sound at effectively all other times and when I am out driving in general.

So did I get this right - Lotus probably designed the car to be louder and sound much better than the US cars do, but in order to comply with (ostensibly California's) most stringent US requirements, they designed the exhaust for a drop in second cat. They would not have scale to design a Cali-based exhaust (most stringent) and a non-Cali exhaust so just provide a Federal US, most stringent option. We think that by going back to the original, non-US spec we get the originally planned sound. Two questions:

Do we believe that for emissions testing outside of Cali, we should pass with this new setup?
Do we believe that Lotus will not see this as in any way impacting our US warranties? I would be happy to ask directly if no one has...

Sorry for the specific questions but wanted to be clear. Obviously I don't hold anyone responsible for their opinions on these two questions.


Finally - I would really like to understand just how much louder this makes the car. I do want more volume but not a ton more sound (just better quality). Critically, when the car is in default mode (quiet mode), can I assume it is still reasonably quieter than the old "loud" mode (with the second cat)? Of course a youtube video compare would be priceless...

 

...
Two questions:

Do we believe that for emissions testing outside of Cali, we should pass with this new setup?
Do we believe that Lotus will not see this as in any way impacting our US warranties? I would be happy to ask directly if no one has...

Sorry for the specific questions but wanted to be clear. Obviously I don't hold anyone responsible for their opinions on these two questions.


Finally - I would really like to understand just how much louder this makes the car. I do want more volume but not a ton more sound (just better quality). Critically, when the car is in default mode (quiet mode), can I assume it is still reasonably quieter than the old "loud" mode (with the second cat)? Of course a youtube video compare would be priceless...

Car should pass non- Cali emission tests without the 3rd Cat, intact would probable pass in Cali too, except maybe not over the 8/10 yr emission performance warranty period that car companies are obligated to. As to Cali regulations, many, many other states (New York for example, there to California emission standards not Federal) so yes the market is very small for a non-cali approved car. Warranty impact, under US law a car company must prove that your part caused a failure. Cat elimination reduces heat loading so mechanical failures would not be caused by its removal, now I hope one has sense to not try to hold Lotus responsible for an emissions test failure.

 

Euro spec cars are a noticeable step louder than US ones - i can assure you!

However with the valve closed they are also very docile and quiet. Still very discreet.

 

Thanks so much JayEmm and Julian73 - all makes sense and it sounds like this is a very viable and exciting and easily reversible US mod! Glad to hear that exhaust volume still very reasonable with valve closed. Thanks too to Texevora for sharing his experience!

 

Thanks so much for the perspective JayEmm and Julian73! Sounds like a great mod option for the US and easily reversible. I think I need this in my life!

 

I am still waiting for the parts. Ordered on the 10th and they still haven't shipped. Can never get a hold of anyone at lotus garage over the phone.

I am thinking about just cancelling the order and getting a custom pipe made.


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I waited several weeks for mine, almost 2 months IIRC. I almost decided to go custom pipe as well, however I didn't think i could find anybody that could do mandrel bent custom piping for the same/lower price as the official Lotus part.

 

Just brought my 400 in to have the second cat removed. pretty excited

 

Did you have to modify the decat pipe (A132S0230F) to get it to fit like texevora did? Let us know how it goes.

 

Keep us posted whether it worked and fit per the diagram previously shown.

 

So, I pulled off my rear diffuser so I could see exactly how the connections worked around the catalyst. The leading edge has a flange that mates up to a similar flange at the end of the exhaust header pipe. These are secured with a V-clamp (that has been loosened in my photo). The other end before the muffler is connected with a slip-on clamp.

It looks like the decat pipe in the diagram (#3) does not have a flange, and even if it did, it would be too short to attach. Even with the wide clamp (#5), the difficulty would be mating the end of the pipe/clamp without a flange like our federal cars have. I'm sure a competent muffler shop could cut off the flange, add some pipe and then either clamp or weld the decat pipe. I was considering this Lotus part if it were something easily done in my garage, but there may be a little more to it.

If anyone does have the Lotus decat pipe and can take photos of it before installation, it might be informative.

 

Thank you for posting that photo. The easiest thing to do might be to pull the cat off and just take it to a muffler shop and have them bend a section of stainless tube in the same length, bend, and ends.

 

@texevora Maybe you can comment as to whether your dealer/tech. used for the install had to modify anything or whether it was a straight bolt-on using factory parts?

 

It was Regogo Racing/Sports Car World in Dallas that did mine. The tech who did the install said he welded an extension onto the Lotus pipe (which was too short), then slightly widened the end of the extension so that it would mate to the manifold/downpipe.

Unfortunately i don't have pictures, but i think that was pretty much it. @DerekOfBass works at the same shop, so he may or may not be able to elaborate.

 

Thanks, sounds like it has to be modified for sure.

 

I work at Sports Car World/Regogo Racing where Tex had his done. The Lotus supplied decat is a simple 90 degree bend with no flanges, and it's too short on the side that goes to the USA downpipes. (so yes.. modifications were necessary).

The exhaust cat is for USA only, and we also get a different downpipe from the headers. I'd guess the non-federal downpipe has a longer extension and no flange on the end.

I think we're going to try to work up an easy bolt-on solution to sell, but I won't have any more info on that for at least another week. Any of you who would be interested, feel free to PM me so we can gauge interest maybe?

 

I'd be interested if you offered an easy bolt-on solution.

 

I was thinking the same thing. You certainly would have first mover advantage! I have to believe it would be easy to manufacture and you’d be able to sell a few to say the least. Thanks again for the insight.

 

Does anybody know what size the mid pipe outside diameter is?

 

@tekkno one method of contact is plenty.. lol! No need to PM me and do mentions in the thread as well.

Like I just messaged him though... sorry for the delay, everyone. Our pipe and exhaust guy is on vacation this week, and I'll try to get him on it when he's back on Monday and email you all when I have some more info.

 

Sorry, I had some issues with my account and I wasn't sure if my messages were going through.

Keep us posted.