I know there are hundreds of threads covering best combinations on exhaust brands and setups including resonator deletes, muffler deletes etc but even using the search function and reading 30 plus threads I still don't clear answers, so here I go:

• Will a resonator delete alter power and throttle response (gain, lose or neutral)
• Will a resonator delete cause drone at cruise speeds (if yes at what RPM), I don't mean drone during hard acceleration
• What is the diameter of the stock muffler pipe as highlight in photo?
• 
  

I intend to keep stock mufflers.

 

Others, please correct me if I'm wrong for the following:

I think if you delete the resonators, you WILL HAVE DRONES especially between around 2K rpms.

I think also with the resonators deletes, you will gain power. This maybe minimum depending on setup. In some instances, there maybe even drop in power.

One thing to note is that on the OEM pipes that goes near the rear "axles" has a nasty bend to it where literally the airflow is terribly compromised and restricted. This is in ALL RCF's (for my year 2015 for sure). With my Borla exhaust this is resolved, but the pipes hang a bit lower to the ground.

I have no idea what the diameter is where you had circled.

Please see the following pics of my pre and post Borla exhaust system installation.


OEM exhaust system before Borla exhaust system. Note the bends and restricted exhaust outflows of the OEM exhaust system.

After Borla exhaust system installed. Note the straighter nonobstructed exhaust outflow afterwards with Borla exhaust system.




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The issue of drone is too subjective to be accurately described on a forum. I do not believe the resonator delete produces any drone at all, not at 2000rpms or any other rpms. It slightly deepens the exhaust note of the car, and it is very mild. I occasionally listen to audiobooks in the car, and the resonator removal isn't even loud enough to disturb that listening or affect my ability to talk on the phone over bluetooth. It's a mild difference. When I think "drone" I think Invidia exhaust on a 4cylinder Honda S2000 (which I used to have back in the day). That produced an intrusive, bassy hum at lower rpms. The resonator delete on our V8 RCF does not, at least not to my ears.

As far as adding HP, the resonator removal produces absolutely no perceptible gain in power. I don't know if anyone has ever dyno tested it for proof (it seemingly would be a waste of a dyno) but I can confirm that whatever gains--if any at all--cannot be felt.

All that said, I think it gives that 10-20% increase in sound that the car needs and should have come with from the factory.

 

i had resnonator delete before i got my Borla. If anything it was too quiet and 0 Drone.

 

Great feedback, 10-20% increase in volume would be fantastic to awaken the V8 rumble as it's very quiet under 4,000 RPM. I have watched clips on resonator delete setups but YouTube clips don't to the sound waves justice, need to hear it in person.

Agreed that "drone" is subjective as what some would consider drone, others would think it sounded like "V8 symphony"

Based on your descriptive feedback I am going to proceed with a resonator delete, asking the exhaust shop to wield in bolt-on flanges so I can interchange the straight pipe with the resonator if needed. In addition going to replace the cheap looking OEM exhaust tip (pre-2016) with titanium blue exhaust tips but going to source longer in length tips to hide the cheap looking OEM setup of where you can see the inner pipe!

I was quoted $550 USD for the job, do you think this is reasonable?

 

Everyone has very different tolerances to drone. Resonators help with vibrations, and drone is caused by those resonant frequencies.

Will you gain power? Even if it is half a horsepower, let's just say no.

Straightpipes do in fact reduce backpressure and may lose performance from doing that alone. At this point, you can easily get a catback that will actually remove the secondary cats and exhaust restrictions. The OEM axelback has disgusting narrowing that I really cannot fathom how it made it from engineering to production. Might as well double the cost, and at least get 12-15 HP with a better sound. $550 for 0 horsepower is money down the drain IMO.

 

Thank you - to be clear I am considering a resonator delete NOT for the power gain as the primary reason, it's pure audio.

But if I was ever to consider a catback on the 2UR, it certainly wouldn't be pushing an additional 12-15 HP from a simple diameter increase and a couple mandrel bends. There are plenty of before and afters videos on catbacks performance on Youtube that yield no HP gains for an investment of $1,500-$2,500 USD. So if we wanted to go power for power, I would say $500 USD isn't a bad deal considering there are zero HP gains as well . Power gains would come from the headers and removal of cats, nothing else.

My questions is; is $550 USD for resonator delete a reasonable ask?

 

What YouTube video? Are you referencing another platform? As mentioned, the OEM is severely restricted. Why would an appropriate exhaust not yield more power?

To answer your question. A resonator delete should be under $200. $550 is a very unreasonable ask.

 

Gains around 20 whp (around 25 CHP) similar in all types of catback exhausts for the RCF. It has been consistently on before/after dynos because the stock piping is too restrictive dropping to even 1.5 inches in some parts. A nearly 100 HP/Liter V8 breathing from a snorkel at high rpms is choking the life out of the power due to stringent emission standards. After resetting the ECU, I immediately felt a significant difference in power over 5500 rpm It is very noticeable from my experience.

Biggest restriction is mid pipe diameter and the nasty 90 degree bend in the axle back section. Aftermarket cat backs remove the nasty 90 degree bend and also increase the mid-pipe diameter depending on the brand. Borla has been discontinued, but Borla increases it to 2.5 inches while Invidia increases it more to 2.75 inches. Borla is louder because it is constructed of thin piping while Invidia has thicker piping and the resonators on Invidia have more refined noise. The secondary cats are also removed which also make the exhaust flow more smoother and with faster velocity at high rpms. Overall quality wise, the Invidia with the Titanium burnt blue muffler tips is unbeatable for around $1200. It looks extremely high quality and maintains it over time (I had mine for almost 2 years now and it looks brand new).

All in all, resonator delete is absolutely not worth the money. The car sounds exactly the same over 5500 rpm in high rpms as opposed to a more pronounced scream with a ful exhaust. You will only notice a difference at idle and slightly louder up till the mid ranges. Also, you will get drone around 2000 rpm under high load situations in tall gears while you get zero gains. For $550, you are getting only slightly more mid range noise, drone and no gains.

 

And see, this is what I meant by subjective. When it comes to sound--just like music--it is totally up to the listener as to what pleases them. If someone had a dB meter and actually measured the difference in sound between totally stock and stock with resonator removal my guess would be in the range of a 10-20% sound gain. It is most noticeable at start up (when my car was started up in the garage after the resonator delete, I immediately noticed the sound increase) and while cruising around town, taking off from a stop. At highway speeds and wide open throttle, no, you won't be able to notice the difference. As you know, under load our cars have a lot of intake noise. It sounds mean, but the sound is coming from up front, not out back. When you add an aftermarket exhaust (headers, catback, axleback or all three) you will get an increased sound from the exhaust, not the intake. That is a more "traditional" performance car sound and what a lot of us are seeking. But to say the resonator delete is not worth the money isn't a factual statement... it is opinion.

Now, is the resonator delete a $550 job? Heck no! It literally took the exhaust shop maybe 15 minutes to do once it was on the lift. Parts are negligible for any exhaust shop. If they have a laser cutter, as most will, they can do it very quickly and easily. $250 would be the absolute max I could see spending on this. Some will do it for under $200. Now welding flanges on may be a little more work, but still, not $550. Find another shop.

Lastly, you will probably end up wanting just a little more sound after awhile. That's how it always goes, right? Just a little more! A cat back exhaust adds power AND sound. You have to make sure the gaskets are good, as more than a few people have had CEL issues that have had to be addressed due to the removal of secondary cats. It isn't a major issue, but it is something to be aware of. And of course you may end up paying between 5x and 10x more for a catback as opposed to the resonator delete. Only you can decide if that extra money is worth it to you. Another option to consider is an axleback exhaust, which many will also say is a waste of money because it adds no HP, but it does add even more sound, especially when paired with a resonator delete. A muffler delete is your loudest, cheapest option, but it is extreme.

 

So funny you say that about an Invidia exhaust on an S2000......I used to have that exact setup, incredible sound, but terrible drone at cruising speeds! It was a love/hate relationship with that exhaust on my S2000! Haha

 

True. Mine was $190 labor + $30 material. However, the OP said his $550 job would include flanges in case he decides to put back the resonators. It also includes better looking tailpipes, so it sounds reasonable. Not sure it's necessary though.

 

Me again, I hit another exhaust shop yesterday. They are recommending X pipe to delete secondary cats & resonators - they said it will increase volume vs. just resonator delete and improve exhaust flow, possibility small HP gain. I will be using stock mufflers.

Does anyone run this set up? What is the sound levels like in cabin at low RPMs?

 

It will sound close to this. It is secondary cats delete and resonator delete. I believe he still has OEM piping, but X-pipe diameter will mostly be influential at higher rpms so it will sound very close to this around idle. Since the mufflers are still there so there will be no drone.

It is a much better option than just going with resonator delete. Sounds great.

 

Thanks 05RollXRS... it does sound more aggressive than just resonator delete, keen to gone done through route. It sounds a little more raspy than just resonator delete but the volume step up is a plus!

At high RPM's it would allow for more exhaust gas flow in 5,000 RPM plus