Went with a true straight pipe... good bye torque ;/

Brandonscarinfo

Member
Established Member
Joined
Jul 7, 2015
Messages
145
Location
Bay Area, CA
Well, I ended up going with a true straight pipe exhaust. The stock cats were removed and replaced with a custom O/R midpipe, because racecar, and the stock x pipe was left intact. The car already has SLP Loudmouth straight pipe ABs on it...

All I can say is... damn. I will try and grab another video that does them justice.... they are nascar loud. A lot louder than I expected. I couldn't find many posts or videos with GT500s with o/r straight pipes...but the few I found sounded amazing.

Unfortunately I lost a ton of back pressure...I have to rev extremely high to get moving, and it's just obnoxious....

When I turn on the car it roars to life...it's amazing... the idle almost sounds slightly cammed out and resembles that of the old school muscle cars. I got a lot of thumbs ups from people while idling at red lights...and even had an old cammed out challenger give me an approving head knod and wave.

Once the light turns green it's terrible. No back pressure and loud exhaust is a recipe for failure. There is also no real tone to it. Just kind of chugging away, for lack of a better description. The exhaust barks at 2k rpms so I shift st 1900 every time so I dont make people deaf. I let it get up to 3.5k rpms and it was just ridiculous... I feel like it's too loud and will attract unwanted attention...I also can't drive the car too late at night now out of consideration for my neighbors.

I really don't want to put the cats back on... so I'm trying to figure how I can keep the amazing burbly idle, regain back pressure and torque, and have a slightly less nascar tone while cruising... if I go WOT I'd love a nascar tone...but for daily driving speeds it isn't suitable.

I never thought I would ever say my exhaust is too loud...but it really is. I'm trying to figure out the most cost effective solution to my problem. I'd love to find someone's old KR mufflers for a couple hundred and throw them on. I think that would help out immensely.... I'm open to other suggestions though.
 

Brandonscarinfo

Member
Established Member
Joined
Jul 7, 2015
Messages
145
Location
Bay Area, CA
Here is the custom o/r midpipe. It was done for the purpose of aesthetics and retaining a "stock-like" look.
7ddef73a8eece48f6060e96892174e03.jpg
 

SCGallo2

Balanced performance
Established Member
Premium Member
Joined
Mar 4, 2014
Messages
1,204
Location
Southern MD

devilish64

Active Member
Established Member
Joined
Dec 31, 2012
Messages
297
Location
Fremont CA
need a chambered muffler.... no cats and stock mufflers work well. no cats and straight through muffler just sound awful to me. my car is longtubes no cats and JBA chambered mufflers and is much quiter than my off road buddies. All in the muffler
 

Brandonscarinfo

Member
Established Member
Joined
Jul 7, 2015
Messages
145
Location
Bay Area, CA
Just not sure if the stock OEM take offs are the way to go, you know?

I still want an authoritative muscle car sound...

I had KR mufflers on my v6 and they were deep and throaty until you got to WOT them they were race car status, which I didn't mind.
 

devilish64

Active Member
Established Member
Joined
Dec 31, 2012
Messages
297
Location
Fremont CA
i felt the same way when i originally did the off road mid pipe.... i felt the car was slower. maybe i just didnt get fully into it because it was so damn loud. a buddy has off road and stock axle back and i love he sound.... other than stock all I can say is chambered muffler. I know ford racing has a nice muffler(svt1 i believe) but its not cheap but it sounds great. good luck
 

SuperFly03

Member
Established Member
Joined
Jul 18, 2009
Messages
620
Location
Tulsa, OK
Shit. That seems louder than mine and I thought mine were a bit ridiculous.

Yeah, putting something on that bad boy to tame it would be a good idea unless you plan for it to be a track only car. Sounds like you loosened up the exhaust too much.
 

Brandonscarinfo

Member
Established Member
Joined
Jul 7, 2015
Messages
145
Location
Bay Area, CA
i felt the same way when i originally did the off road mid pipe.... i felt the car was slower. maybe i just didnt get fully into it because it was so damn loud. a buddy has off road and stock axle back and i love he sound.... other than stock all I can say is chambered muffler. I know ford racing has a nice muffler(svt1 i believe) but its not cheap but it sounds great. good luck
I thought maybe I wasn't getting into it enough...but even at 4k rpms it is still gutless...I don't want to go much higher since the clutch is still breaking in.
Shit. That seems louder than mine and I thought mine were a bit ridiculous.

Yeah, putting something on that bad boy to tame it would be a good idea unless you plan for it to be a track only car. Sounds like you loosened up the exhaust too much.
Yeah...it's nascar loud... definitely going to get pulled over if I leave it like this.

Trying to figure out my cheapest and quickest options.

Had a friend tell me to add a resonator on each side and it should do the trick...but I am not sure if that will work.

Another buddy said to find ANY muffler for ANY car and just have the exhaust guy custom weld it into the exhaust...not sure how that would work.

Any input?
Video clips? Personal experience with cat delete and stock axlebacks even?
 

99SSls1

Member
Established Member
Joined
Mar 28, 2014
Messages
735
Location
Raleigh, North Carolina
No resonator, you have to change the muffler. You get 13/14 dual tips or used and make them fit. I run stock 11 mufflers off-road x and it is loud enough to rock the neighbors at 6am. Race car sound at wot for sure.

do a search on here all the sounds and info are posted already.
 
Last edited:

Brandonscarinfo

Member
Established Member
Joined
Jul 7, 2015
Messages
145
Location
Bay Area, CA
No resonator, you have to change the muffler. You get 13/14 dual tips or used and make them fit. I run stock 11 mufflers off-road x and it is loud enough to rock the neighbors at 6am. Race car sound at wot for sure.

do a search on here all the sounds and info are posted already.
Have any sound clips of yours? Any idea how they compare to a catted slp loudmouth set up (my previous set up).
 

99SSls1

Member
Established Member
Joined
Mar 28, 2014
Messages
735
Location
Raleigh, North Carolina
Not as deep but just as loud. Taking cats out will always create rasp but you have to live with it. Check you tube and I have a in car posted somewhere on here from the 1/2 mile race in Florida.
 

Brandonscarinfo

Member
Established Member
Joined
Jul 7, 2015
Messages
145
Location
Bay Area, CA
Not as deep but just as loud. Taking cats out will always create rasp but you have to live with it. Check you tube and I have a in car posted somewhere on here from the 1/2 mile race in Florida.
Not as deep as a catted SLP loudmouth :/?

I feel like I screwed up then.

Also your previous comment on quad tip exhaust... the 13/14 gt500s come with quad tips oem? How hard is it to make them fit our 07 - 09 valance?
 

Brandonscarinfo

Member
Established Member
Joined
Jul 7, 2015
Messages
145
Location
Bay Area, CA
Yep, that is nascar loud and obnoxious. So those aftermarket cats are hollow? If so, OEM mufflers are probably what you want. Straight through mufflers will do little to quiet it down. I linked a couple of sale items in the market place you should check out.

http://www.svtperformance.com/forums/showthread.php?1079590-Axle-back-systems

http://www.svtperformance.com/forums/showthread.php?1070793-For-sale-08-09-GT500-KR-Mufflers-used-4000-miles

I still don't see the answer to this question.

They are hollow, but there is a straight pipe through them. These go on for the off-road use...and the stock cats go on for the street use
 

RedVenom48

Let's go Brandon!
Established Member
Joined
Sep 29, 2014
Messages
7,973
Location
Arizona
Id just honestly run your offroad pipe and a set of stock GT500 mufflers. I run a similar setup (ORH and stock catback) and its loud as hell at WOT but a little louder than stock when I drive it like a granny.
 

Brandonscarinfo

Member
Established Member
Joined
Jul 7, 2015
Messages
145
Location
Bay Area, CA
Id just honestly run your offroad pipe and a set of stock GT500 mufflers. I run a similar setup (ORH and stock catback) and its loud as hell at WOT but a little louder than stock when I drive it like a granny.
Does the year of the gt500 muffler matter? Someone mentioned the 13/14 and I love the look...but when I search for a 07 to 09 with it I am coming up with nothing... can it be done... or am I better off with going and finding an 11/12 oem muffler?
 

99SSls1

Member
Established Member
Joined
Mar 28, 2014
Messages
735
Location
Raleigh, North Carolina
If you want deeper sound your going to have to get borla touring or something similar. The Oem will work but have a tad bit more rasp. Not sure if 13/14 bolt right up but it looks like you have access to make them fit.
 

Brandonscarinfo

Member
Established Member
Joined
Jul 7, 2015
Messages
145
Location
Bay Area, CA
If you want deeper sound your going to have to get borla touring or something similar. The Oem will work but have a tad bit more rasp. Not sure if 13/14 bolt right up but it looks like you have access to make them fit.
I'm hunting on my local craigslist right now... found a pair of 2012 gt500 mufflers...

No borla, found a corsa extreme... that's about it.
Corsa will be too loud right?
 

brian98svtsnake

Active Member
Established Member
Joined
Mar 21, 2007
Messages
4,618
Location
Monroe township, NJ
I have Kooks LTH's, off rd X and Corsa Extreme and I got warned at a track rental that I was too loud. I believe he said 103 decibels and the max allowed was 98 so Corsa Extremes probably won't help lol. I love the sound but if I have any more problems at the track I might put the stock axle back on.
 

Users who are viewing this thread



Top