2009 Infiniti g37s Coupe exhaust help
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2009 Infiniti g37s Coupe exhaust help
So recently I had a borla catback installed and I’m enjoying it so far but was wondering what my options are to make it louder/deeper.(keep in mind cost efficiency) I don’t want it toooo loud but loud if that makes sense. I’ve been looking into resonated/nonrs test pipes or maybe headers but I’m not sure. Suggestions ? My main concern is raspyness or not being worth the money I paid for the upgrade
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I replaced a catback stock exhaust that had a Top Speed muffler delete on it that sounded way too loud and pitchy when I bought my ‘08 Coupe S a month ago. I do not have a Borla but I do have a Stillen catback that I installed and It sounded good but a bit too subtle. Recently, (last weekend) I installed the Z1 Motorsport high flow catalytic converter kit ($398) to replace the stock cats. The sound is very deep and a bit louder at idle but really “comes alive” at WOT. And I’m very pleased with the sound.
If you look at stock cats from underneath your car, you’ll actually see 2 cats on each bank. I’m not sure why Infiniti has this setup but I’d like to know myself if anyone can chime in on the reason why.
So to answer your question, I would suggest if you still have the stock cats, to replace them with whatever brand of HFC’s you would prefer. Maybe you’ll have the sound you’re seeking. My 2 cents.
If you look at stock cats from underneath your car, you’ll actually see 2 cats on each bank. I’m not sure why Infiniti has this setup but I’d like to know myself if anyone can chime in on the reason why.
So to answer your question, I would suggest if you still have the stock cats, to replace them with whatever brand of HFC’s you would prefer. Maybe you’ll have the sound you’re seeking. My 2 cents.
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I replaced a catback stock exhaust that had a Top Speed muffler delete on it that sounded way too loud and pitchy when I bought my ‘08 Coupe S a month ago. I do not have a Borla but I do have a Stillen catback that I installed and It sounded good but a bit too subtle. Recently, (last weekend) I installed the Z1 Motorsport high flow catalytic converter kit ($398) to replace the stock cats. The sound is very deep and a bit louder at idle but really “comes alive” at WOT. And I’m very pleased with the sound.
If you look at stock cats from underneath your car, you’ll actually see 2 cats on each bank. I’m not sure why Infiniti has this setup but I’d like to know myself if anyone can chime in on the reason why.
So to answer your question, I would suggest if you still have the stock cats, to replace them with whatever brand of HFC’s you would prefer. Maybe you’ll have the sound you’re seeking. My 2 cents.
If you look at stock cats from underneath your car, you’ll actually see 2 cats on each bank. I’m not sure why Infiniti has this setup but I’d like to know myself if anyone can chime in on the reason why.
So to answer your question, I would suggest if you still have the stock cats, to replace them with whatever brand of HFC’s you would prefer. Maybe you’ll have the sound you’re seeking. My 2 cents.
As for anyone else responding a loud idle would be a great bonus .
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I originally was going to have cats replaced at a local muffler shop but they suggested that it would be “tampering” with the emission system by replacing the double cats with a single cat (a $5,000 fine if they were caught). But, they did offer to break loose the nuts and bolts for $100. I didn’t want to drive my car back to my house with a loose exhaust so I went home and got on YouTube and found several good videos on how to remove them and then install new HFC’s.
I bought some PB Blaster and soaked all of the attaching hardware. 2 bolts and nuts on each cat to mid-pipe. All 4 O2 sensor bungs and the 3 bolts/nuts attaching the top part of the cats to the exhaust manifold. For the “demon bolts” at the top of the exhaust manifolds, you’ll have to remove the air intake hoses on each side to squirt them from the top thoroughly.
I had the time so I soaked them 3 separate times over 1 1/2 days (gave me time to install my new brake upgrades) and it was worth it. They all broke loose and with the kit I bought from Z1, everything bolted together nicely. It was relatively simple to do and of course, the satisfaction of doing it myself gave me more skin (flesh) in the game.
If you have the garage, floor lift, jack stands and tools this is a good project to take on. You can do it!
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I originally was going to have cats replaced at a local muffler shop but they suggested that it would be “tampering” with the emission system by replacing the double cats with a single cat (a $5,000 fine if they were caught). But, they did offer to break loose the nuts and bolts for $100. I didn’t want to drive my car back to my house with a loose exhaust so I went home and got on YouTube and found several good videos on how to remove them and then install new HFC’s.
I bought some PB Blaster and soaked all of the attaching hardware. 2 bolts and nuts on each cat to mid-pipe. All 4 O2 sensor bungs and the 3 bolts/nuts attaching the top part of the cats to the exhaust manifold. For the “demon bolts” at the top of the exhaust manifolds, you’ll have to remove the air intake hoses on each side to squirt them from the top thoroughly.
I had the time so I soaked them 3 separate times over 1 1/2 days (gave me time to install my new brake upgrades) and it was worth it. They all broke loose and with the kit I bought from Z1, everything bolted together nicely. It was relatively simple to do and of course, the satisfaction of doing it myself gave me more skin (flesh) in the game.
If you have the garage, floor lift, jack stands and tools this is a good project to take on. You can do it!
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From: Olympia, WA
No, not yet with about 15-20 starts but from Z1’s website, they quote this about their HFC’s:
Z1 Motorsports cannot guarantee that any of the different brands of high flow catalytic converters we sell, including our own, will not cause a CEL (check engine light). From our experience it is not a problem on 90% of cars.
So in the future if my car throws codes or a CEL, I’ll post up separately on the forum to inform all what actions I took to remedy any issues.
Z1 Motorsports cannot guarantee that any of the different brands of high flow catalytic converters we sell, including our own, will not cause a CEL (check engine light). From our experience it is not a problem on 90% of cars.
So in the future if my car throws codes or a CEL, I’ll post up separately on the forum to inform all what actions I took to remedy any issues.
Last edited by CJ1957; Feb 8, 2019 at 01:07 PM. Reason: Add quote
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From: Olympia, WA
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