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YOUR RESEARCHExhaust Sound on a Budget
Leading reported evidence
Replace 4 o2 sensors at the same time
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Performed · outcome unconfirmed
I also replaced all 4 O2 sensors at the same time.
Leading evidence: 'Replace 4 o2 sensors at the same time' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace 4 o2 sensors at the same time' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed · Original poster
Purchased used a Fabspeed Cold Air Upgrade Kit on Craigslist for $100,00 - Fabspeed cost $245 - Did not get the BMC filter although I see one available on Craigslist
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At 1st I used some JB Weld to fill in the slot I cut to install the butterfly.
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Suggestion
I may be looking at replacing my cats in the near future and "Porsche sticker price" has left me speechless.If you don't change the headers is this a reasonable DIY?
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Suggestion
i am going to buy their 200 cell cats but got scared away on their headers (plus I'm not sure that really changes much vs.
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I may be looking at replacing my cats in the near future and "Porsche sticker price" has left me speechless.If you don't change the headers is this a reasonable DIY?
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Suggestion
Reminds me of being a teenager in 1974 and taking the exhaust off my first car, 1971 Dodge Charger with a 318 V8, and running straight pipes from the exhaust manifolds to exit in front of the huge (L60) rear tires/wheels, bitchin!
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Suggestion
At first I felt like my exhaust felt more restrictive and then when I chopped it down to less inserts it felt like the nose wasn�t any better(and some unsophisticated testing with my phone decibel meter showed the same).
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Performed · outcome unconfirmed · Original poster
Purchased used a Fabspeed Cold Air Upgrade Kit on Craigslist for $100,00 - Fabspeed cost $245 - Did not get the BMC filter although I see one available on Craigslist
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26 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
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Generation: 20261026T105141Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
We all know you can go thousands of dollars deep on a great exhaust system. Some do it for the sound. Some do it for performance. Some do for fun, etc. etc.
This is my budget setup:
1. Stock exhaust with the Fister mode. I purchased a pair on Craigslist for $250. Had them modified and installed and then sold my original set back to Fister for $250
2. Top Gear 200 Cell Cats - I was getting an intermittent Cat CEL. Ordered from Top Gear; delivered for $638 to Virginia in about four days
3. Purchased used a Fabspeed Cold Air Upgrade Kit on Craigslist for $100,00 - Fabspeed cost $245 - Did not get the BMC filter although I see one available on Craigslist
The sound has come alive!!! At 3 to 4K there is no doubt heads are turning to see me coming. I wish I would have done a before and after sound track. I friggin love it!!!!
My BUTT Dyno driven by Aural Sensations tells me I have:
Increased horsepower
Increased torque
Increased throttle response
Permanent grin reaction
Eargasms when no one is looking
Just having a little fun here. I do wonder, what the three, four, five thousand dollar systems do that my El Cheapo system doesn't do
Again, just having a little fun here - no need to let me know how stupid, ill-informed, etc. etc. etc. I am - this forum can be brutal.
Ron
911STYL
IMO, the Fister D mod should be standard for all 996s! Couple them with high flow cats and you have the best exhaust mod for the money, especially since OEM cats fail fairly often.
Whoever allowed the 996 to leave the assembly line sounding the way it did should never be allowed to work on premium cats ever again!
I did pretty much the same. I never had a CEL before or after the Topgear parts. I have their headers and 200 cell cats. I also replaced all 4 O2 sensors at the same time. I've put over 10k miles with no issues so far.
I found my Fister style conversion too loud for my tastes. I managed to come up with my own manual butterfly valve in the bypass pipe which I can rotate for sound (fully closed to fully open).
Here is a link to the post to give you an idea how I did it. It works awesome! At 1st I used some JB Weld to fill in the slot I cut to install the butterfly. I later welded it up and it looks much better. You can see the pics of this at the end of the post.
https://rennlist.com/forums/996-foru...-pse-hack.html
I just finished installing the top gear mufflers, considered cats but figured I would save the money for now. I am happy with the sound for the budget, I would rather save money to spend on other aspects of the car.
Not to brag or anything, however, my DIY 996 muffler delete cost me all of like 36 American dollars! Removed the factory mufflers, was able to re-utilize the hardware because it was in decent shape. Purchased two 90 degree elbows ($4 each) and two chrome sport tips ($13 each) plus the tax for a total of about $36. The chrome sport tips exit where the original tips exited, and the sound is music to my ears, not loud at all at idle, but howls like a banshee when accelerating. Yes, I imagine it would drone at a steady highway speed, but the majority of my trips are short, so the modification has been enjoyable so far. Did pretty much the same thing with my 986 Boxster, but had to buy two additional lengths of exhaust pipe to get the tips to exit in the middle as per original, so the cost was maybe 45 American. Same result, quiet rumble at idle, but nasty howl upon acceleration, I love it! Reminds me of being a teenager in 1974 and taking the exhaust off my first car, 1971 Dodge Charger with a 318 V8, and running straight pipes from the exhaust manifolds to exit in front of the huge (L60) rear tires/wheels, bitchin!
Which Top Gear mufflers did you go with? I bought the "mild" version since I thought the "Sport" version was too loud, but now I feel like it is a bit too quiet. I also have the Top Gear headers and 200 cell x pipe cats. I'm very happy with the performance but wish it was a bit louder.
With my old exhaust setup I never had much success with the car chemistry inserts. At first I felt like my exhaust felt more restrictive and then when I chopped it down to less inserts it felt like the nose wasn�t any better(and some unsophisticated testing with my phone decibel meter showed the same).
now I�ve got stock mufflers with Design Tek 200 Cell cats(which I�m 92% sure are the same as the Top Gear). I was surprised at how much the sport cats add. I actually think the noise is pretty good now but could see gundo sounding good without being too much. I�m just so happy to not have the wicked drone between 2,100-2,700 that I had with my old setup.
For those that bought the top gear headers, did you have any fitment issues? There was a user not long ago that bought them and the holes did not line up correctly and last i heard, no response from top gear on why that happened. i am going to buy their 200 cell cats but got scared away on their headers (plus I'm not sure that really changes much vs. oem). I have the sport exhaust.
I had my Top Gear exhaust system installed by an independent shop who recommended by an exhaust shop in Toronto about a year ago (they didn't want to work on the 996). No fitment issues on the headers at the time of install, but I will say that the quality of the hardware (gaskets, bolts, clamps etc.) provided by Top Gear was not up to OEM standards IMO. I stored the car over the winter and when I first took it out this Spring I had an exhaust leak. I took it to the Indy who does all my engine work and he said the leak was coming from the header gasket. I got him to reinstall the exhaust with OEM parts and it has been perfect since.
I did this to mine too and unless the rpms are near redline, the engine sounds like $hit. Doesn't sound like a flat six at all but more like a V6 with a rusted out muffler. Anything above idle is very loud, there is no way to take it easy and be quiet until you leave your neighbourhood, it's loud as soon as you start driving it, regardless how easy you are trying to take it.
Not to hijack this thread, but can someone explain the advantages of the 200 cell cats over stock? I may be looking at replacing my cats in the near future and "Porsche sticker price" has left me speechless.If you don't change the headers is this a reasonable DIY?
My car has the Fister mod exhaust, which I agree should have been stock. My car sounds like it should, esp with a 3.8L Stage II engine.
The 200 Cell cats should in theory increase power as they should flow more air than stock. They are slightly louder from most reports. And as you have noted; they are way cheaper than trying to source stock new cats. As long as you�re state doesn�t have super strict Smog rules you would be fine with them.
Aftermarket converters if daily driven, rarely last more than 4-5 years. That's the main reason CA doesn't allow them without CARB certification. So if you buy a set and need to drive your car every day, make sure you save up for another set too.
