i wanna remove my stock mufflers and run a straight pipe but keep my cat and res, is this a good idea? i heard how it sounds and i like the way it sounds. would this increase the performance in anyway and void warranty?

It will decrease performance. Our cars (N/A) need back pressure to perform at it's best. Putting too much flow and you start to kill low end torque.

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Why have more money than brains? Cuz RACE CAR :

oh snap not a good idea then ill just wait till next spring for my magnaflow catback. appreciate that thanks!!

Sry to thread jack real quick but im gona get my exaust dualed out at the end of the year should i keep the resonator and just run dual mufflers or delete the resonator and run streight pipe to the new mufflers?

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All sho no go...

Keep the mufflers like Anthony said n/a need the back fire. For speedball keep the resonator str8 pipe sounds like ass and was to much drone

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Ditto, and ditto on the res. Your ears will thank you.

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Dubs:00 VW GTI VR6, Low and Slow 91 VW GTI 8v, Shave the Bay!! 91 VW Cabriolet 8v, bitch Basket
GP's:04 GP GT, Past now G-Ma's Girlfriend's 97 GP GT, "Project Pink Power"

X2 keep the rez and run 2 mufflers.

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GPDIY - For All Your DIY Needs
VS CAM|3.4|HEADERS|FWI|42.5#|HPT|6000k LOWS|8000k FOGS|

I said nothing about any back fire!! Lmao! I said back pressure.

I'm getting ported stock exhuast manifold just cuz my headers and 3" downpipe kill my performance

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Why have more money than brains? Cuz RACE CAR :

DON'T DO IT!!!!

I did this for a cruise I was going on with a bunch of ricers (If you can't beat em, Join em). Prior to hacking off my mufflers, I went to the 1/8th mile track in the spring and was hitting 10.2s all day. I did an HV3 and my "muffler delete" and my best time out of 25+ runs from 2 different nights was a 10.5 something.

Not only did I lose power, but the drone is rediculous, and it backfires all the time! I am getting mine welded back together the first chance I get. Oh, thats another thing, I can't find a clamp to put them back together because of the way the pipes are bent, They will HAVE to be welded back on! I can get you an exhaust clip of mine before I get it welded back together if you'd like.

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Only people that should go with straight pipe are peeps with turbos cuz the turbo creates the back pressure already needed.

-- 7:25pm Sep/11/2010 --


I was apart of a group like that but got bored of them quick cuz most of them didn't know how to work on their own cars and they we all immature. Then I found my current car club SSP . Most of the members are like in their 30's with Z06's, mustangs, Gto's like crazy, and a few imports... And there r only 3 GP's there so far. 2 others with 3800's though.

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Why have more money than brains? Cuz RACE CAR :

Typo Anthony Geeze

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Truth.

I run a cutout and dump right after the down pipe. Sounds nasty, scares the shit outta people, and makes more power.

IMHO a SC or NA car would be better off with just buying a nice Stainless catback for sound. Better than hacking everything up IMHO.

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04 GTT - Retired
Best ET 13.016
Best Trap 115.56 MPH

??? R u talking about that guy in Tampa? - I really don't like him much.

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Why have more money than brains? Cuz RACE CAR :

I will probably get bashed for this.

I run Straight pipe with cat and res back no mufflers, the sound I have to admit I love because its a rumble you dont normally hear, surprising the rasp is not present at all.

As for power loss, I have had this done since 50k ( now at 150k), All scans show no power loss or little of a gain depending of the RPM. Once tuned it was more fuel efficient and the sound was changed once again to a lower rumble. Fuel - City- 25-27MPG Highway - 55MPH - 42MPG, 65MPH - 35-37MPG, 70MPH - 27-31MPG. -- This was per the Laptop running a scan over a 8 hour period of driving ( while I was going from Indianapolis to Kings Island lol ).

Now I have to admit its LOUD but IMO its worth it. If you want I can do video got HD on the new phone

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2004 Grand Prix GT AGGRESSOR
PRJ PCM, Custom Exhaust, 180 stat, FWI Custom Intake, DIC upgrade.

What are your 1/8 and 1/4 times buddy?

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Why have more money than brains? Cuz RACE CAR :

From the whole Tampa meet months back everyone seemed to run str8 pipe personally was way to loud and rasp for me and would drive me insane if I would have to hear that all the time. Exact reason why I kept everything stock except the mufflers saved some money and my ears love it.

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Not sure since the tune, Not expecting good times due to the tune is set for gas mileage for the winter.

Then again the track hasn't been a big thing this year even though its right down the road.

-- Sun Sep 12, 2010 2:03 am --




With having the dynamate in the trunk you dont really hear it. This ^ is what got me interested as I was curious what benefit it had - once I got into tuning and worked with it a little finally stated to make sense, as I was always told back pressure is key to the NA. But from the tune there is a benefit removing some back pressure but that also concerns if your running factory manifolds.

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2004 Grand Prix GT AGGRESSOR
PRJ PCM, Custom Exhaust, 180 stat, FWI Custom Intake, DIC upgrade.

Well, if you still have all the exhaust piping running to the back bumper and it's not 3" in diameter it will still create quite a bit of backpressure so it wouldn't completely kill low end torque, but if you just hacked the exhaust off at the DP or a cutout then goodbye backpressure and low end torque on N/A. Anything boosted doesn't need any backpressure to make power, though it still should obviously have some sort of exhuast manifold/headers to create a scavenger effect.

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Dubs:00 VW GTI VR6, Low and Slow 91 VW GTI 8v, Shave the Bay!! 91 VW Cabriolet 8v, bitch Basket
GP's:04 GP GT, Past now G-Ma's Girlfriend's 97 GP GT, "Project Pink Power"

The Exhaust is 2.5 all the way back.

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2004 Grand Prix GT AGGRESSOR
PRJ PCM, Custom Exhaust, 180 stat, FWI Custom Intake, DIC upgrade.

lets see some videos please

Will attempt to do that today.


Not the best but heres one from my phone.
RPM Ideal - 780 RPM

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2004 Grand Prix GT AGGRESSOR
PRJ PCM, Custom Exhaust, 180 stat, FWI Custom Intake, DIC upgrade.

sounds pretty good