I'm wondering if anybody can give me any feedback on swapping out to a Borla Axle Back Only exhaust. I've found lots of info on the full cat back but not much on just the axle back.

Wondering about drone at highway speeds mostly. I'm not adding headers or deleting cats as this will be a road trip and daily car.

Thanks in advance.

 

Borla never made an axle back for the RCF. The catback has been discontinued for some time and hard to find. When they (cat back) goes up for sale on FB people are getting at least $1,500+ for it. I'd honestly say you have two options. Keep the stock mufflers and replace the midpipe. Or get a quiet cat back exhaust. Depending on the manufacture changing out just the mufflers (axle back) might be much louder than stock. IE: Changing to GT haus/meisterschaft axle back is pretty loud by itself. Someone on the FB group had an Apexi axle back and complained it droned and was horrible until paired with a midpipe. Some folks change the mid pipe to an Apexi (resonated or non resonated) and keep their stock axle back.

One thing to note is that the Borla wouldn't even connect to the stock midpipe by default. See below picture. It's clamped to their mid pipe sections. So if you were able to get a Borla (which would include everything for a catback) you'd have to weld on flanges to their axle back section or cut the flanges off your mid pipe... which if you are doing all that you might as well install the entire catback.




I know you said you didn't want to delete cats or go with a full catback but there are options. Ideally if you change the exhaust you'd like to see some benefits unless you are going for looks only. But the Invidia is a very good option. I and many others have it on their RCF. It's not loud, or obnoxious at all. In fact many people say it's on the quieter side of exhausts. I can honestly say it's perfect for me. It's not loud until you really get on it and even then it's not to the point that I can't have a conversation with my wife beside me in the car, talk on the phone via bluetooth, or listen to music in the car. There is ZERO cabin drone while driving, both city/highway speeds, which was extremely important to me... in fact that was one of the deciding factors of picking an exhaust. It couldn't have any drone, I'm past that crap in my life. I've had a car for 15+ years where I did the exhaust and the drone on the highway was just not fun...

Many people DD their cars with the Invidia exhaust and love it. Cold starts sound amazing and then it just mellows out. Small slight rumble at idle, no where as quiet as stock, but not loud like some of the other systems out there.

-Nigel

 

The only reason why most people choose the Invidia is because of price point, plain and simple. If you can get someone to fabricate the midpipe section for this Borla exhaust, it would sound a lot better than any Invidia offerings.

 

That is absolutely patently false. You don't speak for the owners who make the decision. It is entirely a subjective choice. When I purchased mine, I had both Borla and Invidia available back in early 2019 almost 3 years ago. I looked through both options very clearly before making a decision. I chose Invidia because in my own personal taste and opinion, I did not want to make my RCF sound like a Mustang.. It is not a muscle car so I wanted the smooth, melodic, higher pitch and sophisticated sound that the Invidia clearly had.

Also, Invidia quality is way better.

 

I've heard both of these exhausts in person and driven RC F's with both early on. Choice is subjective and so is sound preference. My observation is most people go with Invidia because of price point. Don't take it personal Faisal.

 

I'd disagree and agree at the same time. I disagree about the price point and why people choose it. Both the Borla and Invdia are roughly the same cost. I could have easily bought the Apexi mid pipe wth Tom's axle back (which I still want), however, the number of people that have that setup and have posted videos and or verified that there is little to no drone is not nearly as many people who swear up and down that the Invidia was drone free. Hence my main deciding factor for choosing one exhaust was the lack of drone. I didn't want to end up buying an exhaust only to be like this sucks, and then have to take it off and go through the hassle of selling it locally.

I 100% agree with you that sound is so very subjective. What someone thinks is awesome because it's super loud and insane, I just shrug my shoulders and say, "been there, done that, not doing it again"... that doesn't mean it's bad, just not for me. As same point where I think the Invidia sound is great while someone else is thinking "this is too quiet".

I will note that the borla mid pipe section that connects to the headers IS superior because it has the recessed area (just like the OEM midpipe) for an OEM crush gasket (which I think ALL exhausts should be, but sadly they are not), where as the Invidia and most others (even Apexi midpipe) uses a flat gasket... which in my opinion the OEM gasket is superior and I would have loved to have been able to use that reliably with the Invidia. However, with the borla I am not a fan at all of "clamp"style connectors all throughout the exhaust. I'd much prefer a bolt on like the Invidia. I like that the tips are both welded on both borla/invidia, where as the Tom's (still really like this exhaust!) is clamp on. I get why they did that because of different diffusers, but paying $3k+ for an exhaust is ridicluous that the tips are clamped on like Pepboys/AutoZone tips and not welded...

I wish we did have more clear video's and or user experiences of different exhaust setups. If money was unlimited I'd buy them all and try them out..lol, well probably not the meisterchaft,, $10k for an exhaust system is silly when we aren't talking P-car, Ferrari, Lambo..etc.

-Nigel

 

I've been looking everywhere and can't find any sound clips of what I was looking at.
I'm aware that Borla didn't make JUST an axle back, however I was talking with a guy at a shop that does lots of Lexus projects and he was cleaning out some left over parts-- to include just the axle back sections of what was once a cat back system.
I've built enough really loud exhausts on other platforms to be cautious this time about overdoing it and/or creating a droning situation. I absolutely do not want any drone with this car.

I appreciate you guys input on this as this platform is completely new to me. The resonator pipe seems to be a pretty big deal with these cars so it's good to learn this now before I buy something.

I may be leaning towards an Invidia or a valved system---if I can find one that's under 2k.

Thanks again.

 

The invidia is amazing. If you want a great sounding RCF, great price for what you get, no drone and all the bark you want when you bean it, you would be making a HUGE mistake to go with any other exhaust. Anyone who knocks the invidia is just bummed they paid twice as much as they should have for their exhaust and it has drone. The only nuisance is that you, personally with your own eyes, have to make sure the install of the front gaskets is sufficient enough to create a good seal. I did my own install and it was easy peasy and I was easily able to see what would cause the problem and layed a nice layer of copper exhaust gasket seal there to be sure it was mint.
Trust us, that have it and advocate for it. You don't hear any Tom's owners on here saying it would be a mistake to not spend 6k. Yeah, the brand name is cool, they sound amazing, but I drive my car everyday and the other options are just too loud for a daily.
Check out my insta for some sound clips @throttle_therapy_nh. There are a few clips of idle, tunnel, and highway pulls.

 

If the Borla was still a choice, that one be one of my top picks for the RC F. Two reasons, the sound and the reputation. If price was not an issue, Meistershaft/MUSA and TOM's would be my top picks. My personal favorite is the Apex'i N1-X with non resonated for the RC F and most likely what i'll end up with on my RC F. Not sure why this turned into an Invidia exhaust ad. I personally think it's too tame for what you're paying for.

 

You cannot use an axle back part of a Borla exhaust because it simply won't be compatible with the OEM mid pipe. The length of the OEM axle back and mid pipe is totally different from the Borla. I just installed (I did the install myself) an RR Racing Valvetronic Bazooka which is basically the Borla with different mufflers and valves or at least is made to be compatible with the Borla but looks to me pretty much the same... The OEM axle back (muffler part) goes all the way to the mid hangers in the system and the Borla system has the hangers in the midpipe section, these connect at a different point compared to the OEM system so if you were to use the Borla axle back, you'd need to get somebody to weld or attach an extra section to include the hanger legs and be able to reach the OEM midpipe and hanger points, not to mention that the Borla uses the clamp system so you'd need to also weld the flanges to connect to the OEM....... I think the Valvetronic Bazooka system is probably the best option out there as far as sound, price and performance. It's not cheap by any means, at almost $3k, but you do get the valve system that can quiet it down almost to OEM (a bit louder and deeper but close) or have it loud as the Borla with the push of a button. GT Haus is another option with valves but at about $5k, I think it is too much for what it is imho.