Exhaust-ed, Need Sound Advice
 

My current setup is:
JDL 4-2-1
2.5" stainless OP
Factory FP
3" resonated Perrin CB

(What I'm looking for is some personal accounts of what would be effective to reduce dB's, below is my context)

I originally opted for a 2.5-3" transition FP but was entirely too raspy. So I reinstalled the factory FP which helped tremendously but is still too loud for longer sustained trips.

The crossroads I'm at is chopping up the 2.5-3" FP and welding in something that will be quieter than stock. I'm just not sure what that would be. I'd prefer to avoid a cat to keep it free flowing for the sake of the SC, but I'm open to the idea if there's some first hand accounts that a resonator/s won't have the desired effect.

The option I've been looking at is some Corsa resonators. The length of the FP would allow for as many as 2 full sized and 1 stubby resonators if it took that much. The long 3" is rated at a 6-8db reduction, long 2.5" at 4-6db, and a last resort addition the stubby 3" 2-3db.
My question is how would this compare to the factory FP, or to using cat/s? The last thing I want is to spend a few hundred dollars in resonators just to be equal to or worse than the factoy FP.

Could weld resonator in the oem front pipe. That will give you the "Ultra Quiet" frontpipe effect. Also, try to trade in 3" CB for 2.5" CB. Other than that is catted header

JDL EL 4-2-1, Ultra Quiet FP (with GESI cat), 2.5" Perrin CB. Not loud at all, other than startup. I think sizing down the CB is your best bet.

I have the exact same exhaust and am very happy with it.

I had an exhaust shop weld this into the stock FP and remove the stock resonator but left the cat alone. Worked very well. Had a 4-2-1 header as well stock FP with mod, stock mid pipe and an axleback with good results

Vibrant 1140 2.25" Ultra Quiet... https://www.amazon.com/dp/B000E3VHW8...p_mob_ap_share

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As others said, ditch the 3" Perrin catback. Greddy Supreme SP catback would be a logical choice.

Or, the factory midpipe and the Fujitsubo Authorise S axleback muffler.

It's funny, in my one tracked mind I hadn't really considered adding something to the factory FP. I love the tone of the Perrin 3" and I hate the thought of ditching it. So I will try adding a ultra quiet resonator to the FFP and see if that does the trick. I'm thinking that it will it's not too far off as is.

I had a similar setup (JDL 4-2-1, Stock OP and FP) with the Invidia R400 - was great for a few years when I was doing more city driving, but over the last few years with a move, if I am driving for work/pleasure, it's been all highway.

The combo was boomy, drony and fatiguing overall right in that sweet spot at 125-135kph. The catback on its own was great, but as soon as you add a header onto these cars, you need to be much more careful with exhaust selection.

I ended up reinstalling the OEM catback - it's a night and day difference. I can actually hear my own thoughts on the highway now! I do miss the tone of the Invidia a bit for sure, but having a much more comfortable highway driving experience is worth the trade off - if I get bored of this setup I may just go with a mild axle back like a Fujitsubo Authorise S.

https://youtu.be/GFNPIROddoY

Good luck, should be interesting. I just don't think you're going to be able to tame a 3" exhaust, but in for updates.

I've got a decent mic I'll do some before and after clips and post them in here.

I suspect you’re right. Just to add one data point, about 6 months after after I bought my car in 2015 I installed a Yonaka CB. It’s been on the car ever since, with several 1000 mile plus road trips. If you listen closely you can hear it on the highway, but mostly during throttle tip-in.

I haven’t seen them for sale in years, but mine is exactly what I wanted.

I forgot about that brand! Nice! Looks like they're still for sale, FWIW: https://www.yonaka.com/FR_S_BRZ_GT86...p/ymcb-frs.htm

Yeah, the single entry dual-exit canister/suitcase style mufflers are really the only way to quiet down this car/engine. Anytime you go to dual canisters (or 3" piping for that matter) you're just doubling your exhaust's audible volume level basically.

People get catbacks and complain but in reality they need axleback. The stock Midpipe have long ass resonator and it can quiet down any catless header.

That company is local and I've eyeballed buying it for a year now.