Borla Cat replacement pipes


HPGT

GT Owner
Jul 31, 2012
82
Little Rock, AR
I'm going to install Stillen X(H) pipe, and I also had to check on
my half shaft bolts. I have Borla cat replacement pipes. Now
I'm wondering if I need to wait on the Borla pipes until I check on
the loudness of the X pipes. I know a lot has been posted on X pipes
and loudness - I just thought someone might have knowlege on these 2
brands together - or a thought on the sound insulation of the Borla cat replacement
compared to the stock cats.
 

nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,196
It is hard to give you a subjective measurement of "loud", but the Borla Cat Deletes in conjunction with an X/H pipe is going to be pretty dang loud. The only "muffling" that you have going on will be the resonator in the Borla pipes and these are quite a bit less restrictive than the OEM CATs. The stock CATs do I surprising amount of muffling. (Note: Disconnect your negative terminal at the battery to insure that you don't accidentally bump the otherwise hot cable at the starter.)
 

HPGT

GT Owner
Jul 31, 2012
82
Little Rock, AR
Thanks - I think I'll just put the Borlas on the shelf and just do the X pipe for now.
 

Triheart7

GT Owner
Mark IV Lifetime
Apr 3, 2007
2,576
Northern California
My pipes were very loud about two years ago until we discovered a crack in them. A new set eliminated a lot of rattles and noises inside the car. My neighbors love the quieter car. I only feel inadequate when I am around Ed Sims. His make mine sound like a hybrid! LOL.
 

HPGT

GT Owner
Jul 31, 2012
82
Little Rock, AR
My pipes were very loud about two years ago until we discovered a crack in them. A new set eliminated a lot of rattles and noises inside the car. My neighbors love the quieter car. I only feel inadequate when I am around Ed Sims. His make mine sound like a hybrid! LOL.

Were the stock pipes cracked?
 

BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
Were the stock pipes cracked?
I think it was a Heffner H pipe. Mine had a crack in it too on the bracing connecting the left to right side.
 

Triheart7

GT Owner
Mark IV Lifetime
Apr 3, 2007
2,576
Northern California
Black Ice is correct!
 

Wwabbit

GT Owner
Mar 21, 2012
1,259
Knoxville, TN
I just finished that swap today as a matter of fact. Have had a GTG X pipe for long time with cats. Loved the sound and nice pops and crackles. Removed cats and replaced with the Borla cat-delete pipes. I had the cat-deletes ceramic coated yesterday. Sounds a lot stronger, the healthy pops I used to get are replaced with nice manly bangs now. But overall, it's not terribly louder than the stock cats. I didn't want an ear busting car, just trying to free up a few more horses. Here are the pipes (before ceramic) and after installed. Have to bed in new brakes, so road test tomorrow. Will report back.

cat delete.jpg

exhaust.jpg
 
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HPGT

GT Owner
Jul 31, 2012
82
Little Rock, AR
Thanks Wwrabbit for the validation. I was beginning question my judgement on the reasonable limits of sound tolerance. I will probably hold back on the Borla pipes until I get used to the X-pipe sound.
It's possible that the ceramic coating might help with the sound - keep us informed.
 

Wwabbit

GT Owner
Mar 21, 2012
1,259
Knoxville, TN
I gave it a good run today. It is for sure a bit louder with the cat-deletes, I'd say by 25-30%, but it has the same character. The ceramic should not have an effect - I did that for heat mitigation. Interestingly, the sound change is in low frequency and with more sound pressure. More things vibrate. Exhaust pops are stouter.Definitely NOT a ball buster on sound, tolerable. And you can always short shift it for stealth. I think I like it, but we'll see. Going to a track end of the week for 3 days- that will tell the tale. Your'e plan seems like a good one, start with just the X-pipe and move up from there. I'll let you know how next weekend goes.

JS