CallawayOwnersGroup.com

Hi Group,

I'm a new owner of a 2013 Callaway Grand Sport that I purchased a few months ago. It is a manual transmission and I'm very happy with the performance of the car so far. One thing that I would like to improve is the sound of the car. Currently the car is stocked with CATS and Callaway DD mufflers. My question is how can I make my car more bolder and deeper in sound? I also have a 67 427 big block with side pipes which sounds great. I know I cannot duplicate that sound with this car but I would like to get as close as possible. Does anyone have any experience with changing the DD mufflers out to Borla or Flowmasters? Has anyone installed headers and straight pipes on a 2013? I would like to keep my drone to a minimum if possible. I'm looking for any ideas on how to improve the sound of the car.

I appreciate any feedback that you guys might have and thanks ahead of time for your help.

Before I changed the mufflers, I’d do long tube headers and high flow cats.

Thanks SurfnSun!

The Callaway double D should sound good already

I have the same car -- 2013 SC606 -- and was in the same boat as you, i.e. wanting more sound. I changed out the DDs for Borla ATAKs (axle backs). My understanding from speaking with Callaway was changing the axle backs was ok, i.e. wouldn't affect the tuning, but once you start in on the mid pipe and manifolds, now you're impacting the tuning. Maybe Callaway Chris can confirm please? I've never noticed an change in performance running the Borlas.

In any case, I'm considering either going back to the DDs or finding a different set of used axle backs, perhaps Corsa Extremes or Billy Boat PRTs. The Borlas sound good but they are loud when cold and I think they drone a bit at times/certain RPMs. I do like the look of my Borla setup though -- I'll try to post a pic later.

I've also considering getting a different x-pipe, like a Corsa or Borla non-catted x-pipe to cut down on some of the heat from the cats. But that brings me back to the tuning issue, so I always drop it there.

I think I've come to realize one will never be able to replicate the sound of long tube headers, etc.. with just a change out of the axle backs. So might as well just keep the Callaway fully intact, rather than start "cutting and carving" on it. Might as well just get a Z06 and start there.

Sorry for the rambling post -- just my thoughts on my situation at this point in time!!! Hope it helps!

SurfnSun wrote: ↑Sat Dec 28, 2019 12:26 am Before I changed the mufflers, I’d do long tube headers and high flow cats.

Does that impact the Callaway tune? My understanding from Callaway is that it does impact the tuning.

Long tube headers would likely impact the tune a little bit. Probably best to at least dyno and check AF ratio

Here is what another owner told me who added long tubes.

It got louder and it has some resonance. With new headers the cats r also gone. I wanted to save the double d exhaust. If u don’t have one u could just change the mufflers and be good.
Or
You could add the larger injectors and a little smaller pulley don’t bother with headers and get a good bump in power. That way it would stay nice on the highway for you.
Just use a trusted tuner to keep the car safe and u should be good. I can do a sound clip for you if that would help. Just tell me what u want to hear.

Fletch wrote: ↑Fri Jan 03, 2020 10:42 am

SurfnSun wrote: ↑Sat Dec 28, 2019 12:26 am Before I changed the mufflers, I’d do long tube headers and high flow cats.

Does that impact the Callaway tune? My understanding from Callaway is that it does impact the tuning.

It does. Car will need to be recalibrated. This, primarily due to the changes in manifold pressures from the different cats, if any.

Thanks for the info guys!! Really appreciate it!!
Fletch, I was thinking of the Borla's ATAKS, how much drone do you get, too much?
Really don't want to do headers, high flow's, tuning right now, hoping for a simple way out.
Thanks Vetteman

Vetteman wrote: ↑Sat Jan 04, 2020 3:39 pm Thanks for the info guys!! Really appreciate it!!
Fletch, I was thinking of the Borla's ATAKS, how much drone do you get, too much?
Really don't want to do headers, high flow's, tuning right now, hoping for a simple way out.
Thanks Vetteman

Honestly, I'm not sure if it is drone or if it is just how loud they are. They are definitely loud and "seem" to drone when cold but again not sure if it is drone or loudness. I notice it more when windows are all up. When windows are even slightly cracked, it seems to let the resonance out that comes from the rear hatch area. I'd say there is some drone when at highway speeds and RPMs are low and I need to accelerate slightly going up a hill. Otherwise, just cruising around town with the windows down when warmed up, it is just loudness and popping and burbling upon deceleration, which I definitely like. So, long story short, I'm torn!!!

I with you on wanting a simple way out. At the end of the day, it comes down to personal taste and simply trying different axle backs to find the one that you like. Buy used on the various forums is a good way to sample around.

Here’s a pic of my Borla Atak setup.

If no drone and loud is the goal...Corsa is the answer.

Callaway Chris wrote: ↑Fri Jan 03, 2020 4:31 pm

Fletch wrote: ↑Fri Jan 03, 2020 10:42 am

SurfnSun wrote: ↑Sat Dec 28, 2019 12:26 am Before I changed the mufflers, I’d do long tube headers and high flow cats.

Does that impact the Callaway tune? My understanding from Callaway is that it does impact the tuning.

It does. Car will need to be recalibrated. This, primarily due to the changes in manifold pressures from the different cats, if any.

Thanks, Chris. Would the vehicle need to be brought back to Callaway to do the recalibration? Thx.

Thanks Fletch for the info and picture of the car, looks great!!
Yea, think I will try and find something used, Borla's sound like what I am looking for, as like loud, but we are going to take the car on trips so drone will be a problem maybe.
Corsa's are nice, have them on my 2000, wish they had the deeper tone I like.

Vetteman wrote: ↑Sun Jan 05, 2020 1:05 pm Thanks Fletch for the info and picture of the car, looks great!!
Yea, think I will try and find something used, Borla's sound like what I am looking for, as like loud, but we are going to take the car on trips so drone will be a problem maybe.
Corsa's are nice, have them on my 2000, wish they had the deeper tone I like.

Yep that was the main reason I went with Borla was the deeper tones vs the more “exotic” tones of the Corsa.