[Nummeister]

Originally Posted by oldman

I don't but you can order a full 3" with twin center resonators and NPT exhaust. IMO it will be too loud. The car does NOT need 3" exhaust with your build... and the minimal IMO power is not worth the increase sound level.


Put it this way say the 3" is worth 10 topend HP over the 2 and 3/4 (I don't think so but lets say), and the 2 and 3/4 with resonators will be stock or even quieter than stock cat back that you have. That is an awful lot of money to pay for 10 top end HP. Even the 2 and 3/4 if you ask me is worth say 5 to 7 HP over the stock cat back and we know how ugly the stock system is.

Maybe we should clarify, are you doing an exhaust from HP, if you are I think you will be disappointed. Are you doing it for a quality sound and a little HP and just because the stock cat back is SO ugly? In that case I'd go 2 and 3/4. If you are doing it because of HP, then my friend I'd just put QTP cutouts and that sucker is going to give you zero restriction and be as loud as your want, but quite otherwise.

If you just need to quite what you have down, we have near identical cars and builds, just put the Borla 60608 mid stream problem solved. Don't look under the car don't think about the crush sections. The factory X pipe BTW is actually a nice piece and as long as you don't look or remember how ugly the factory stuff is.... you will be super happy... Remember even the HIGH dollar Lingenfelter / Hennessy bulbs keep the factory cat back upto and over 1000 HP... I'm so lazy, I was going to slide hammer out the factory crush pipes and tig up the holes, but said nay, it ain't gonna give me any HP.

So I ended up getting the 3 inch Borla catback exhaust. Holy hell!! This thing is super loud!! And don’t get me started drone on low rpm. Drivability in low speed is horrible. It was driving me crazy! I def. will have to get the Borla 60608 to quiet this thing down or hope to. My question is, will the 60608 interfere with flow as it’s 2 3/4 diameter and rest of my exhaust is 3inch?

[oldman]

There are no flow issues, the 3”is too big; but I already said you would be unhappy with it, I don’t think the 2.75” 60608 mid is going to fix that. The stock header is only 2.1”ID with a lot hotter gas (gas law) so the 2 and 3/4 presents no restriction till you are say 800 up engine HP and even then it ain't huge. I further restriction and 3” is just too big for your power level. Hope you got the S type muffler? Your still thinking flow and even the stock system with 1/2 the flow was good enough.

[Nummeister]

Originally Posted by oldman

There are no flow issues, the 3”is too big; but I already said you would be unhappy with it, I don’t think the 2.75” 60608 mid is going to fix that. The stock header is only 2.1”ID with a lot hotter gas (gas law) so the 2 and 3/4 presents. I further restriction and 3” is just too big for you power level. Hope you got the S type muffler? Your still thinking flow and even the stock system with 1/2 the flow was good enough.

I did get the s-type muffler. What would be your suggestion to quiet the noise and drone?

[Nummeister]

Originally Posted by oldman

There are no flow issues, the 3”is too big; but I already said you would be unhappy with it, I don’t think the 2.75” 60608 mid is going to fix that. The stock header is only 2.1”ID with a lot hotter gas (gas law) so the 2 and 3/4 presents. I further restriction and 3” is just too big for you power level. Hope you got the S type muffler? Your still thinking flow and even the stock system with 1/2 the flow was good enough.

Maybe put stock X-Pipe mid pipe back on and keep the S type muffler in the back?

[oldman]

the factory X pipe is just slightly smaller than the Borla that is not going to do anything. You will find zero change in sound. I have a question as almost everyone has the attack Borla. The S muffler is straight through correct? Best do the 60608 and make sure your valves are closed when you drive from your home.

[oldman]

This is why I went to the resonators (Borla 60608) mid-stream combined with the factory chamber muffler at the back. The youtube does a very good job explaining why any straight thru system does not make the best over-all sound.

https://www.google.com/search?q=cama...GcIhQ8xajAE4M:

https://www.camaro6.com/forums/attac...1&d=1445853610

[Nummeister]

Originally Posted by oldman

This is why I went to the resonators (Borla 60608) mid-stream combined with the factory chamber muffler at the back. The youtube does a very good job explaining why any straight thru system does not make the best over-all sound.

https://www.google.com/search?q=cama...GcIhQ8xajAE4M:

https://www.camaro6.com/forums/attac...1&d=1445853610

Thank you for all your advice. One of the pipe came loose that cause the loud noise and drone issues. Tighten it all up and most def. made a huge difference. I took your advice and ordered the 60608. Thanks for all the advice!