I spent a lot of time researching catted downpipes and I quickly learned that they aren't cheap. I also read time and time again that you shouldn't cheap out on a downpipe because cheaper ones have bad welds, they rust quickly, or that they don't fit well. But I'm an impatient teen with a low budget, so I searched for a cheaper catted downpipe. I found the PLM Downpipe on eBay, and I recognized the brand from friends and YouTubers with Honda's, Subaru's, and other Japanese cars. After digging through the forum, I found just a couple of posts about the catless PLM downpipe, but there was no mention of the catted one. There was only one YouTube video of the PLM downpipe, but it too was catless. I decided to go ahead and purchase the catted downpipe because I trusted the manufacturer. I went to thier website, ordered the part, and they gave me a number to track my order through a Shopify app called Shop. I ordered it on a Friday afternoon and it shipped from San Francisco to North Florida in 5 days.

Upon opening the package, I was shocked by how heavy it was. All of the welds looked good, and the lower mounting brackets were rock solid. I did notice that the welds around the O2 bungs, the brackets, and either end of the pipe were colorful and very precise. I assume that they were done by hand, as compared to the welds on the cat itself, which were thick and less precise. The welds are not bad at all, but they're not going to blow you away like the HDT or Akrapovic Downpipes. The inside of the pipe looks alright, but the transition from the cat to the ends of the pipe aren't completely smooth. The catalytic converter definitely looks less restrictive when compared to the stock cat; I'd say it's half the density. It is a 200 Cell cat, according to PLM. The downpipe also came with two o2 sensor spacers and a new downpipe gasket.

I had my neighbor help me with the install because he's put downpipes in WRX's, Jettas, and more. The install went smoothly, but one problem we did run into was getting the thing past the exhaust manifold. I can't remember if it was the flange or the cat that got stuck, but we had to use a jack to push the pipe up far enough that we could get the bolts in with an impact driver. Other than that, the V-band was a pain to get on, but that's probably the case for any downpipe. The O2 sensors fit perfectly and we did use a spacer for the bottom sensor in hopes of avoiding a CEL.

Before I get into the sound and function of the PLM Downpipe, I would like to make it clear that the rest of my exhaust system is fully custom. It uses full 2.5" piping and a Vibrant Performance "Ultra-Quiet" resonator (Part 1141). So there's no secondary cat and no muffler. It already sounded great with that setup, but I wanted a deeper tone, more volume, and louder/more frequent backfires.

Upon starting my car with the PLM Downpipe, I noticed that it was only a little louder, but the tone was considerably deeper. Revving the engine revealed that it was far less muffled than before. You can hear a bit of turbo noise in the exhaust, but not as much as a catless setup. My neighbor and I hopped in my car and took it for a ride, and I could tell that it wanted to burble and backfire even before the engine was up to temperature. The first backfires were no different than normal, but I floored it in second gear and it backfired like crazy. It burbles a lot more than it used to and the big backfires are far more violent. Driving through a busy residential area, the exhaust turns a lot more heads than before. I guess that's a good thing considering that it sounds like there's a shootout in my trunk. Old people seem to hate my car even more, but I've already gotten a handful of compliments in the few hours that I've driven with the new downpipe.

As for the performance of the downpipe, I can tell that it's a little more responsive, but it's nothing major. The car feels less sluggish under boost, and I can tell that the downpipe flows much better than the stock one. I don't care about making more horsepower or torque and I can't say that I noticed a major increase in either, but I'm satisfied with the results.

One last thing: I did get a CEL, even with a spacer for the o2 sensor

So, in conclusion, I'd say that the PLM Catted Downpipe for the R-series Minis is well worth the $300 that I paid for it. It greatly improved my exhaust sound, even with a custom setup, and the fit and finish seems perfectly fine. The ordering and shipment process was fast and easy, which is a bonus.

I'll post some pictures below and I will update the thread if I have any issues down the road. Feel free to ask questions here or through DM's.

 

https://privatelabelmfg.com/products...xoC-eMQAvD_BwE

Here's the link to the downpipe. Please note that you have to select the catted option. And I think you can ignore the "retail price"; I've been looking at this downpipe for months and it, just like most stuff from PLM, has always been listed as on sale.

 

Inside upper section

Inside lower section








o2 sensor spacer

 

That looks pretty good.

 

That doesn't look like a cat converter, it looks like a "cat converter"...that is, I suspect it's just some expanders welded together to look like a cat and there's no actual catalyst matrix in there. That would probably explain the CEL.

 

There's a cat in there, I promise. It looked very similar to a roll of cardboard, like this picture. The CEL is because The o2 sensor readings aren't within the tolerances set by Mini.

 

Where in Florida are you located? I live in Panama City Beach. Would be nice to have more local or semi local Mini owners near by. There is only one other that I know of on here.

 

High flow cats seem to always throw a CEL, I use to just run a cat less downpipe and swap it back to stock before bringing it to get a state inspection. When I use to swap it often I could get it done in about 30 minutes. Did you remove the heat shield on the front of the block and studs from the turbo before installing it? Those would always hang it up if you didn’t take them out unless you just forced it in there.

 

I removed the studs but I didn't remove the lower heat shield. I had to use a car jack to force the new downpipe into place lol

 

I'm just south of Jacksonville. I haven't taken the time to find a Mini club around here yet but I see tons of modified Minis in my area.

 

Yeah you really should have taken that off, it’s just 4 bolts, all 8 or 10mm on the sides of it and makes the whole process a lot easier.

 

When I did mine, I left the studs in the turbo, took the top heat shield out, unbolted the bottom one but left it hanging out down there while I swapped the pipes out.

 

Yeah, I agree. I got my downpipe install instructions from various YouTube videos and none of them removed the lower heat shield, but a couple of them did have the same issue. Luckily, my state doesn't have inspections, so I shouldn't have to do that again any time soon.

 

Day 2 Update: I'm loving this downpipe! My exhaust is burbles a lot more, and the burbles are much deeper. The moderate backfires are about the same as before, just louder. There are a lot more of those super-loud "gunshot" backfires compared to before, and they are LOUD. The overall tone is deeper, and it sounds so much better under acceleration. The engine sounds a lot bigger than it is, and I've seen some people do double-takes when the hear my exhaust and then see my car. 10/10 would recommend going resonator-only with high-flow downpipe, as long as you don't mind a loud car. There's a difference between a loud exhaust setup and one that sounds great, but this exhaust setup is both.

 

Update: my car hasn't been running right for the past month or so. Laggy throttle, rough startup/idle, reeks of exhaust in the cabin, not backfiring loud enough to startle the police... I honestly thought the cat in the downpipe finally got clogged. The A/F ratios have been good and it's still making good power up top so I didn't think it was a big deal. I finished my finals yesterday so I finally had time to take a look at it. First off, the turbocharger is literally covered in soot. Like, matte black. I unbolt the heat shield and you won't believe what I see. Not one, not two, but ALL THREE studs on the turbocharger are missing, along with the gasket and part of my sanity. I have no clue how this happened because I used an impact to tighten them when Installing the DP. But I also noticed just how corroded and nasty the DP looked.

I could just order the studs and gasket but I think I'm going to order a catless downpipe while I'm at it. The PLM downpipe did okay but it's not great. Any recommendations on sub-$300 downpipes? So far I like WMW, Milltek, And CTS's options. Should I go with something like the $200 ebay pipes instead?

Tl;DR: All three DP studs fell off and the PLM DP is already a rust bucket.
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Can't say I ever heard of the turbo studs working themselves out. Get a new set, along with gasket and nuts.

I have the Way Motors cat-less downpipe. Bought it used, and have had it installed for ~100k miles or so? Still looks like the day I bought it, and haven't had any issues with it.

 

Did it throw a cel?

 

I had the car tuned to turn off the CEL

 

Oh got it
From my readings it looks like all the downpipes throw a cel,i'm I correct in saying that?