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I am looking to replace my failing catalytic converters on my 987.2 Boxster. Do any of you have experience with Topgear’s manifolds & cats? My main goal is to avoid emission concerns and CEL’s. I live in Oregon, USA. They are much cheaper than Fabspeed or Soul cats but lack the HJS German 200 cell. Any input would be great! I have a completely stock car with OE systems.
Yes. I just put them on my 2007 Cayman S. I had a variety of old and new on the car when it came to me and wanted to baseline back to a new setup, soup to nuts. Brandon at SRD said that Hartech recommends them.
The workmanship is georgeous. People talk about drone. I think we all have different expectations of what that might be but I do not find them offensive in that regard. But there is definately noise that makes it into the cabin, both at cruise and hard acceleration.
All of this assumes your 987.2 is similar to my car. Here are some issues.
1. The hardware kit did not include the pieces I felt were necessary to support the mufflers off the rear of the transaxle. I had to fabricate my own support system. The first article linked below has some discussion about that.
2. The cats are 200 cel and they did throw a CEL. The second/third articles linked below describes how I dealt with that.
Yes. I just put them on my 2007 Cayman S. I had a variety of old and new on the car when it came to me and wanted to baseline back to a new setup, soup to nuts. Brandon at SRD said that Hartech recommends them.
The workmanship is georgeous. People talk about drone. I think we all have different expectations of what that might be but I do not find them offensive in that regard. But there is definately noise that makes it into the cabin, both at cruise and hard acceleration.
All of this assumes your 987.2 is similar to my car. Here are some issues.
1. The hardware kit did not include the pieces I felt were necessary to support the mufflers off the rear of the transaxle. I had to fabricate my own support system. The first article linked below has some discussion about that.
2. The cats are 200 cel and they did throw a CEL. The second/third articles linked below describes how I dealt with that.
Just read the articles, nice work. My 987.1 just started throwing P0421 as well, so the timing is great. New OE downstream sensors didn't correct it in my case, so I assume the cats are aging.
Which o2 sensor bungs/spacers did you buy, and I assume you only installed them on the downstream o2 sensors?
Yes. I just put them on my 2007 Cayman S. I had a variety of old and new on the car when it came to me and wanted to baseline back to a new setup, soup to nuts. Brandon at SRD said that Hartech recommends them.
The workmanship is georgeous. People talk about drone. I think we all have different expectations of what that might be but I do not find them offensive in that regard. But there is definately noise that makes it into the cabin, both at cruise and hard acceleration.
All of this assumes your 987.2 is similar to my car. Here are some issues.
1. The hardware kit did not include the pieces I felt were necessary to support the mufflers off the rear of the transaxle. I had to fabricate my own support system. The first article linked below has some discussion about that.
2. The cats are 200 cel and they did throw a CEL. The second/third articles linked below describes how I dealt with that.
Thanks for the reply. I’m really hoping Topgear would suffice as their price is much more affordable. You have a 3.4L engine correct? I have a 2.9L with all OE parts. Could one assume a CEL would be less likely if i’m putting out less CO2 with my engine? I will most likely use new OE gaskets and hardware. Not too familiar with how these systems work but i enjoyed your write up.
The 2nd article tries to explain how the downstream sensors work, with respect to the upstream sensors. Yes, only on the downstream sensors. I got the bungs from Amazon. They are nothing special. Start out with the straight extensions. That might solve your problem. It's a pretty simple job once you take off the wheels and some of the splash shields.
I doubt that the engine displacement has any affect. As discussed in the article, they are using an algorithm to compare the upstream and downstream gas streams.
I don't know about OR. In some jurisdictions, a knowledgable inspector may spot the bungs and gig you but they are pretty well hidden up in there.
The 2nd article tries to explain how the downstream sensors work, with respect to the upstream sensors. Yes, only on the downstream sensors. I got the bungs from Amazon. They are nothing special. Start out with the straight extensions. That might solve your problem. It's a pretty simple job once you take off the wheels and some of the splash shields.
I doubt that the engine displacement has any affect. As discussed in the article, they are using an algorithm to compare the upstream and downstream gas streams.
I don't know about OR. In some jurisdictions, a knowledgable inspector may spot the bungs and gig you but they are pretty well hidden up in there.
I’m hearing that most aftermarket cats can cause CEL’s on 987.2s since their emission system is very sensitive. My question now is if the Fabspeed or Soul HJS cats from Germany are practically the same. Or maybe they have more precious metals and is why they are twice the price of Top Gear.
It is of course a difficult thing to predict (duh). BTW, if you haven't picked up on it, there are warm-up cats, the small ones just downstream of the engine, and their are main cats, downstream from there. The only cats that get evaluated by the ECU are the small warm-up cats. Anyway, if you currently have a stock system and are just getting the one code, I would try the extension bung and see if that fixes the problem. That is by far your lowest cost solution. Like $20 plus your time. If that doesn't work, I would contact some local independent Porsche shops, anywhere in OR, and see if they have real time experience. Nothing against forums but there can be a lot of mis-leading info thrown around.
BTW, when I purchased my 2007 Cayman, the PPI showed problems with a cat on one side. The seller agreed to replace it. He found an aftermarket one for < $700. It worked. So although the Top Gear kit is very nice, you are looking at serious money to go that route. It just depends on what your goals are.
BTW, I don't know where you live in OR, but @Zirconocene in Portland might be a good guy to chat with. He is just an enthusiast so not trying to sell anything. Also, I bought my Cayman in Portland and probably could find the name of the shop that did the PPI. They seemed like good folks. Let me know.
It is of course a difficult thing to predict (duh). BTW, if you haven't picked up on it, there are warm-up cats, the small ones just downstream of the engine, and their are main cats, downstream from there. The only cats that get evaluated by the ECU are the small warm-up cats. Anyway, if you currently have a stock system and are just getting the one code, I would try the extension bung and see if that fixes the problem. That is by far your lowest cost solution. Like $20 plus your time. If that doesn't work, I would contact some local independent Porsche shops, anywhere in OR, and see if they have real time experience. Nothing against forums but there can be a lot of mis-leading info thrown around.
BTW, when I purchased my 2007 Cayman, the PPI showed problems with a cat on one side. The seller agreed to replace it. He found an aftermarket one for < $700. It worked. So although the Top Gear kit is very nice, you are looking at serious money to go that route. It just depends on what your goals are.
BTW, I don't know where you live in OR, but @Zirconocene in Portland might be a good guy to chat with. He is just an enthusiast so not trying to sell anything. Also, I bought my Cayman in Portland and probably could find the name of the shop that did the PPI. They seemed like good folks. Let me know.
I appreciate the info. I’m probably going with Top Gear cats but then using a Softronic tune to deal with sensitive CEL’s. Even with the tune, the price i’ll pay is much cheaper than the alternatives.
Now that I check, I actually bought the extensions from Walmart mail order. I see Summit Racing also carries them. Just google Oxygen Sensor Extension and a lot of options come up.
There is no need to weld on a new bung. The extension go in the bung where your downstream O2 sensor goes and then the O2 sensor screws into the extensions.
BTW, if your warm up CATs have truely failed, these extensions aren't going to make the CEL go away.
Just read the articles, nice work. My 987.1 just started throwing P0421 as well, so the timing is great. New OE downstream sensors didn't correct it in my case, so I assume the cats are aging.
Which o2 sensor bungs/spacers did you buy, and I assume you only installed them on the downstream o2 sensors?
I went through this a few months ago, Bank 1, or passenger side. I solved it by buying a pair of cats/manifolds off a guy converting his car to dedicated track. If your issue is Bank 2, driver side, PM me and we can discuss the left over cat/manifold sitting in my garage.
02-08-2024, 02:43 PM
Topgear Exhaust Manifolds & Cats
