TRD exhaust restrictive?
 

Years ago I picked up a TRD exhaust off some kid for dirt cheap. I never expected any performance gains, but I do love the sound of it. Right now I’m upgrading the rest of the exhaust and other parts. I’m wondering if the TRD catback is gonna hold me back from any potential gains. Im going with a Gruppe S catless header + overpipe, Invidia catless front pipe, Injen Evolution intake, and a OFT Tune with E85, so I’m expecting a decent power bump. However I probably am not ever going to go turbo.

I know the TRD is 2.5” except for a section that is 2.25” for some reason. The Invidia is 2.36”. As much I love the sound of the TRD, I’ll likely get a new catback if I would be losing any potential gains here.

No. It's well documented that catback exhaust systems have negligible impact on the naturally aspirated FA20 performance

You will not lose any real performance but it will be freakin' loud and drone like a sonofabitch without the cats.

Ditch the intake if you plan to run OFT. It will throw off the MAF scaling. They recommend keeping stock air box.

I tried a TRD exhaust with stock front pipe and gruppe-s header/OP. It droned like a MF from 1000-3500 rpm. Particularly bad on deceleration around 3000rpm.

Fully catless will likely be worse, maybe a dual resonated front pipe will help with some of the drone, but unlikely to kill it all.

The only catback that doesnt seem to have any drone (according to owners) is the Corsa.

Every one else seems to have various levels of obnoxious drone, volume and sound.

The only real gains you get from an exhaust is going from stock to aftermarket. After that you're likely just comparing an unnoticeable 1-3hp difference between the aftermarket options.

I had zero "drone" with the TRD on the FRS but it was specifically designed for the stock headers and cats. I have heard it on a couple of cars with different headers and no cats and it is like a totally different exhaust. Sounds like a fart can Honda. It is horrific!

The caveat with that catback is that it's designed around the rest of the system being stock. Once you start switching other parts it will be loud and may drone.

I ran one for a couple of years and it's a great system if you don't plan to add headers.

Thanks for the replies dudes!

Really?? Man that’s disappointing, I was really excited about the potential performance of the Injen box that uses the snorkel. Seems to be the ideal intake. There’s nothing that can be done about the MAF scaling?

Oh god, yikes. The front pipe is resonated, as is the TRD midpipe so I was hoping the two resonators combined would tame it a little bit, plus I figured the TRD muffler was a little quieter than other options. I already had the Invidia FP on there and still loved the sound, but I’m sure new headers will have a much bigger impact. I’ll probably fire it up just to see how bad it is, I’m not too worried about droning as its just a weekend car now, but I definitely don’t wanna sound like a farty Honda

Any suggested catbacks for my setup that would actually sound good?

Sorry no recommendations as the different combos are almost infinite.
The only reason I know how the TRD sounds with no cats is that I loved the deep tone on my FRS and was a bit surprised to hear what it turned into on other cars not using the stock cats and header.
@RToyo86 can probably give better suggestions as he has tried a few set ups.

Yes you can/or get the maf scaling right.

A MAF rescale will definitely help. Once dialed you maybe get 3-6whp? Based on information buried inside the forums. Take that for what it's worth.
A high flow drop in filter and a aftermarket inlet tube on the OEM air box will net a few whp with a tune and doesn't need rescaling.


As of right now I'm on gruppe-s headers/OP, HKS dual resonated front pipe and the stock catback.
Catless frontpipe even dual resonated added a touch of rasp down low with the stock catback, but otherwise it's a nice subtle daily setup if you don't want to attract much attention.

You can sort of hear the setup hear via video at the bottom
https://www.ft86club.com/forums/show...0&postcount=65

Depends on what you are looking for from your exhaust setup. I want zero drone and a different tone without being much louder. My next purchase if I decide to pull the trigger is a CSG touring catback. One of the most quiet options for this platform being designed around catless setups. Different headers, front pipes effect things so much it'll be hard to get a straight answer since one different part can change drone/tone a lot.

So with MAF rescaling/custom tune, the Injen should still produce a little more power than the stock box right? Because it’s in shipping right now, I’m not even gonna open it if the stock airbox ultimately produces better power than the Injen in the end.

As for the exhaust, I kinda want loud. Not absurdly loud, but still loud. And I’m not too worried about droning. It’s just a weekend cruiser now, so I’m changing out all powertrain mounts too, the car is gonna be rough and noisy lol. But I really would prefer to keep that low, deep exhaust tone if possible.

Will it make more power? Sure.
According to information available you can make a smidge more power with an aftermarket CAI but nothing is guaranteed.
Whether that is worth the few hundred and data logging required to dial it in is up to you.
A drop in filter and Perrin inlet tube is $150 compared to $300+ for most CAI's.

As far as exhausts go, you generally get what you pay for. Maybe check out vendors like FTspeed and see what is still available.
I have heard UEL setups locally with Magna flow catbacks that sound good and aren't deafening loud. If you have a local club meet ask for ride alongs. First hand is always the best way to figure out what you like.

Look into getting Borla and tomei parts it sounds better than the invidia parts IMO