What's the power/sound difference with a catback?

[wrapfee]

Hi everyone. Just picked up a 21 3.0 Premium and am jealous of the 20 exhaust note. I'm here to ask stupid questions since I did zero research on this car before buying it (have a 21 NSX on order and recently sold my Evora 400, which left me without a toy car and I couldn't pass up $6K off on this car).

Anyway, a lot of cars (including the NSX) get most of the power/sound gains from a high flow cat or catless downpipe, since with the valves open is basically bypasses the mufflers.

Is it the same with the Supra? Or will a catback system + downpipe be noticeably better (either power or sound, or both)?

It's always tough to tell by YouTube videos...but the ones with the HKS system seem to be my favorite (and it got the most votes on this forum's poll). Also intrigued by the module Magnaflow system....

Any thoughts or advice? I'm looking for mostly sound at this point. Will hold off on a tune to see whether or not the 21 ECU ends up being unlocked.

Rambling...similar subject...I'm sure power gains are almost zero with a CAI...is there an improvement in sound? Any recommendations on intake, exhaust, or both for what I'm looking to do would be awesome.

Oh, already have the Active Autowerks catted DP ordered.

TIA.

Sponsored

 

[Rocksandblues]

They really pick up sound and power with catless downpipe.

Why did you sell Evora? I was just looking at one this week

 

[wrapfee]

They really pick up sound and power with catless downpipe.

Why did you sell Evora? I was just looking at one this week

Thanks man, I appreciate the feedback. I was just looking at the Remus unit. Valves open makes it basically straight pipe / bypasses the muffler. This is the type of setup I'm looking for, but Remus requires cutting and I don't want to do that.

Do you know of any valved exhausts that do that (open valve = muffler bypass)? Preferably controlled by factory Comfort/Sport modes, rather than with a separate fob.

On the Evora...I had a 17 Evora 400 6 MT. It was a fun car, especially on winding roads. I didn't have a specific reason to get rid of it, I was just antsy for a change. I happened to stumble upon a buyer and Acura is currently doing $20K rebates on the 21 NSX, so it was just the right timing. I've wanted an NSX since they were relaunched, but I always expected their values to plummet because of weak sales, but that hasn't been the case. So I pulled the trigger on the deal.

If you are looking at an Evora 400/410/GT, I think you'll enjoy the handling. It's comfortable around town, and a beast on back roads (handles much, much better than the Supra). Sounds pretty good too if you eliminate the extra cat on USA cars (GRP has the pipe for like $300).

It's fairly well built for a Lotus, but nowhere near the build quality of the Supra. You can tell they are hand built. The infotainment and stereo is a joke (it's literally an Alpine head unit that you can get at Best Buy, 4 (crappy) speakers, and a (also crappy) sub).

If you go with a pre-owned Evora, you can buy an aftermarket warranty from Fidelity. I did once my factory warranty expired last year (I bought it from Audi of Coral Springs...I didn't buy the car there, but I had a relationship with them from an R8 I bought there years ago, and they were happy to sell me one). Platinum (exclusionary) coverage with a $250 deductible for $3,700. 4 years and 48,000 miles. Would highly recommend for peace of mind.

If you have any specific Evora questions, I'm happy to help (or PM me directly).

 

[Rocksandblues]

I have a titan catless with jb4. The jb4 has an option to keep valve open all the time. With about 7 track days it seems to me that has gotten even louder. I don’t have any proof but it feels like the long hard track days are packing down whatever insulation is in stock mufflers Dunno. As cars keeps sliding more and kore into just track toy I will probably just go straight pipe

Don’t have any actual experience with which valved kit. I would go AWE if you want the loudest.

No way I should be looking at a third track toy. Lol. Was in a dealership with family member suv shopping and they had this sitting there. Really looked hot in person

New NSX are really cool with the 3 electric motors. I can’t believe you will be disappointed
Good luck

 

[Benjilis]

I have a titan catless with jb4. The jb4 has an option to keep valve open all the time. With about 7 track days it seems to me that has gotten even louder. I don’t have any proof but it feels like the long hard track days are packing down whatever insulation is in stock mufflers Dunno. As cars keeps sliding more and kore into just track toy I will probably just go straight pipe

Don’t have any actual experience with which valved kit. I would go AWE if you want the loudest.

No way I should be looking at a third track toy. Lol. Was in a dealership with family member suv shopping and they had this sitting there. Really looked hot in person

New NSX are really cool with the 3 electric motors. I can’t believe you will be disappointed
Good luck

How do you keep the Callie open with the jb4?

 

[Rocksandblues]

How do you keep the Callie open with the jb4?

It’s an option

 

[Benjilis]

It’s an option

Where?

 

[Rocksandblues]

Where?

It’s a simple left stalk button control. If you hold it it the blinker will flash
Hold and right flash and it follows sport button
Hold and left blinker flashed it’s forced open.

From memory. Google it to be sure

 

[wrapfee]

I have a titan catless with jb4. The jb4 has an option to keep valve open all the time. With about 7 track days it seems to me that has gotten even louder. I don’t have any proof but it feels like the long hard track days are packing down whatever insulation is in stock mufflers Dunno. As cars keeps sliding more and kore into just track toy I will probably just go straight pipe

Don’t have any actual experience with which valved kit. I would go AWE if you want the loudest.

No way I should be looking at a third track toy. Lol. Was in a dealership with family member suv shopping and they had this sitting there. Really looked hot in person

New NSX are really cool with the 3 electric motors. I can’t believe you will be disappointed
Good luck

Thanks man, I appreciate the insight. I definitely want to go with a valved exhaust if I can (optimally straight piped with the valve open). I had my R8 straight piped, no valves...and it was MEAN sounding. My neighbors surely didn't like me very much. I liked the option to be church mouse quiet once I enter my neighborhood.

Good info on the JB4. I'll probably end up picking one up at some point unless an OBD flash becomes an option.

Looking forward to the NSX. It takes a lot of heat online, but I've really liked it since it debuted. I have SoS downpipes sitting at the Acura dealer already. Told them to not even tell me when the car arrives until the pipes are installed and it's ready to roll.

With my luck, I'm sure a few weeks after I take delivery, prices will fall off a cliff, haha.

 

[jonesxlv]

AA Catted DP + AWE Resonated Touring and it sounds really mean without the wild rasp from catless. It’s a 7.5/10 in terms of volume from 3500-6000 RPM. Here’s a vid:

 

[wrapfee]

AA Catted DP + AWE Resonated Touring and it sounds really mean without the wild rasp from catless. It’s a 7.5/10 in terms of volume from 3500-6000 RPM. Here’s a vid:

Sounds awesome! Does it retain the factory valve system for comfort/sport modes?

 

[jonesxlv]

Sounds awesome! Does it retain the factory valve system for comfort/sport modes?

Unfortunately not. But wasn’t important personally.

Sponsored