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YOUR RESEARCH996 3.4 Exhaust Options
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One of the best muffler modifications I have used on the 996 is to have the stock mufflers cut in half, remove the enternals and re-weld the mufflers back together.
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Seriously considering but would doing what you recommend the same as a muffler bypass but weigh a bit more????
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Thus, I have two options: 1) repair the PSE by having an exhaust shop open and repair loose parts in the PSE muffler or 2) replace the mufflers.
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Thus, I have two options: 1) repair the PSE by having an exhaust shop open and repair loose parts in the PSE muffler or 2) replace the mufflers.
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Would new mufflers combined with their matching cats from the same Mfg improve performance or just the "sound" as compared to the repairing the PSE mufflers?
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Would new mufflers combined with their matching cats from the same Mfg improve performance or just the "sound" as compared to the repairing the PSE mufflers?
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But I discussed changing the stock exhaust with both my Indy mechanic (Porsche certified) and the a friend who has raced cars and both strongly recommended against it given the number of people who they have seen change a 911 exhaust only to regret it.
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But I discussed changing the stock exhaust with both my Indy mechanic (Porsche certified) and the a friend who has raced cars and both strongly recommended against it given the number of people who they have seen change a 911 exhaust only to regret it.
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Hello everyone
What do you get the most benefit from in changing either the manifolds or the "end boxes", there is a german outfit selling Stainless manifolds on the bay �580 claiming 8-10% power increase , sounds good to me !
a) power
b) sound
c) weight
Budget, at the moment, doesnt stretch to the full works !
Appreciate views from those of you who've upgraded the exhaust, seems a shame to have a 911 without the full sound sensation !
Rick
10% of 300 HP would be 30 right? May sound good - but all the post I have seen on Rennlist would seem to say it would take a lot more money to get that kind of improvement in a NA M96 motor - and far more that just one part of the exhaust system.
Two articles, replies to letters, in Excellence have stated that there are very few proven full exhaust systems on the market that they have tested and seen a "noticeable" improvement in power. I happen to have one of those - a full TechArt Header System. But even that @ $3500 is only claimed to get 28 HP - With a DME Remap and intake air-cleaner filter mod.
HP improvements on most E-Bay ads are like "Snake-Oil" sales at the Carnival - but you can believe it and spend your money. I suggest you talk to a good Indy before you run your charge card.
As a rule of thumb, always take HALF the HP that the manufacturer of an aftrrmarket claims. In this case, 4%. 12hp at the crank, on a 300hp engine will not be noticable. Buy it for the sound.
Well, be very careful because most times you will actually lose power from some of these aftermarket exhaust componets, especially low-end. Most of the time, the power curve just gets moved around, meaning you may get a little more power at the high RPM range but you will lose low-end torque. I know of two companies that actually design, build and "performance test" their exhaust system components specifically for performance. These companies are Cargraphic and AWE. There may be others that I am unaware of.
I have some related questions as I have a damaged "Cat." I am considering Cargraphic and Fabspeed replacements with 200 cell Cats.
I also have OEM, PSE with a rattle on one side. Thus, I have two options: 1) repair the PSE by having an exhaust shop open and repair loose parts in the PSE muffler or 2) replace the mufflers. Would new mufflers combined with their matching cats from the same Mfg improve performance or just the "sound" as compared to the repairing the PSE mufflers?
Lastly, what about the headers? Are the Stock headers good enough or would it make sense to replace them along with the Cats? ...and possibly the mufflers?
Basically, the question comes do whether or not all three parts together are required to reap any real benefits as compared to just changing the cats.
Also does it require other parts or ECU programming to truly get a performance benefit of any or all of these exhaust mods- as compared to just some volume and tone changes?
Thanks!
Stock exhaust manifolds are good enough. Headers will not add much if anything to performance and---you run the risk of snapping exhaust manifold bolts, especially on an older car. I would replace the Cats (Cargraphic or AWE) and go with the 200 cell. As far as mufflers---do you want to retain the PSE?? If so get them repaired. Aftermarket mufflers will not really increase performance but will sound better. Best muffler modication--IMHO, is to gut the stock mufflers and add 200 cell cats. Great sound and performance enhancement..
Per Alpine003, "And more importantly for a street car, I would rather have more improvement "under the curve" rather than all out peak hp."
I was all gung-ho to change to the Afterhours Sport primarily for the sound (not too loud, but a nice growl when you get on it) and because it did not appear to negatively effect low end rpm performance (see dynocharts on their website). But I discussed changing the stock exhaust with both my Indy mechanic (Porsche certified) and the a friend who has raced cars and both strongly recommended against it given the number of people who they have seen change a 911 exhaust only to regret it. I'm still tempted given the "wife friendly" design of the Afterhours Sport, but haven't pulled the trigger yet. BTW, I have a Cabriolet, so definitely am sensitive to too loud.
One of the best muffler modifications I have used on the 996 is to have the stock mufflers cut in half, remove the enternals and re-weld the mufflers back together. This makes them extremely light, gives a great sound (not loud supprisingly) and good performance. Hergesheimer MotorSports in Lake Forest, CA used to do this modification, but I would think it could be done by others with the right tools (welder, grinders, etc.). We are currently running this setup with AWE 200 cell cats on my friends track car and it works very very well. And again, it is not loud and there is no drone. Has a great sound!
As we talked about today.... The stock Headers are the best (unless you really plan on going racing... then you would see the most benefits from a remap to maximize the system), upgrade to set of 200 cell cats and go with the Super Sound version. The system will work across the full RPM range without low end torque loss and no remapping needed to see about 7 to 10 hp gain.
Drop me an email and I can work up the cost for you.
PmKazz I know you talked about the gutted mufflers before but just wanted clarification that there is no drone even with the 200 cell cats and the mufflers were FULLY gutted with no baffles or insulation whatsoever? TIA
Correct. Completely gutted. No drone... The best way I can describe it is, it sounds very Ferrari-ish.. The mufflers by themselves sound incredible, but much better with the 200 cell cats. And----There was NO low-end loss of torque with this setup and we have experimented with a a number of combinations. PM me if you want to discuss more...
Regarding using 200 Cell cats, Do you need to replace the oxygen sensors?
...should they be replaced at the same time or just use the existing ones?
...both "before" and "after" sensors?
Thanks!
Reviving this old thread....the gutting is an interesting option that I had not considered. My 996 is pretty much a dedicated track car with some aftermarket exhaust that I don't like the sound of but it is lightweight. SO I have been considering other options to maximize the following benefits:
1) Great sound with no drone
2) Lower weight
3) More horsepower (though I am concerned about low end torque)
I have been considering the following:
1) Gundo hack my current low weight after markets
2) Just spend the dough and go for Fabspeed Maxflo
3) Muffler bypass - Low cost, low weight and loud probably bad for low end torque
Thoughts?
S
Seriously considering but would doing what you recommend the same as a muffler bypass but weigh a bit more????
What did it cost you to strip the internals?
I would not do muffler bypass. There are a few things that are required in exhaust systems and your car. One is some back pressure. Long story but trust me.
Cost depends. the company that did the original set charged $700. because there some labor involved. You can probable do them yourself if you have some some cutting and grinding tools and a good welder. And of course you know how to weld well.
You could always do the exhaust that is guaranteed to give you serious power. You know the one with the turbine attached to the exhaust... LOL Tpc turbo kit
For the money, you can't beat the Fabspeed cans if you're looking for a good mix of sounding pissed off while remaining refined enough for daily driving.
Capt. I agree, however if I go the Fabspeed route its got to be the Fabspeed Supercups and those are a little steep on price.
My original cans are just laying around collection dust and I think it will be fun experimenting with them, but if I'm going to do all that work I don't want it to sound just like a muffler bypass.
Steepsnow:
I have added the FisterD Stage III Titanium Sport mufflers and Speed Venture X Pipe with 200 cell high flow cats. I noticed immediately the improvement in performance, and sound and continue to do so every time I drive my car. The speed venture system is equal to the fabspeed system, IMHO. My buddie has the same setup as mine except that he paid about $500 more for the Fabspeed X pipe and high flow cats. I drove his car before he did the upgrades and I have driven it since the upgrade. My car feels stronger and it just feels solid. Again, just my opinion and I like to share with my fellow RL'ers
Good luck on whatever you decide
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