: Impressions: Gibson Exhaust Installed Today



wake
03-10-13, 01:19 AM
Installed my Gibson exhaust today. Impressions are mixed, love the sound, not so much the appearance.

Sound: Very slight drone but very livable in my opinion, nothing vibrating in the vehicle. Very nice sounding rumble, kinda reminds me of the Flowmaster Force II system on my C4 Corvette.

Appearance: Not real crazy about the appearance of the exhaust. I'm not sure if it's the trend today but why do almost all aftermarket exhaust systems I see have the tips stick out past the end of the bumper? I shoved the mufflers as far forward as possible, enough that I will have to trim some of the plastic splash guard on the driver's side because of interference. With what appears to be the default position the tips stick out about 3" past the end of the bumper, not a good look to me. I may see if there's enough meat for an exhaust shop to take the long tips off and replace them with something a bit milder. It also needs to go into an exhaust shop to have some pipe work done to line up the driver's side muffler. After an hour I gave up and clamped it up, hanging about 1" lower than it should. I don't think it's anything to do with the stock pipe as the stock mufflers sat level, looks more like a slight bend needed in the aftermarket muffler pipe.

Observation: Saw something I've never seen in the 3 months I've owned the vehicle. On my 30 mile drive with the new mufflers on the fuel AVG fuel economy actually ticked up a couple of tenths. I started with 19.8 mpg AVG after my 100 mile work commute, ticked up to 20.0 during my mostly non-highway drive, and was back at 19.8 mpg by the time I put it back in the driveway after I flogged it a few times to get a good feel for the sound at WOT. I've never driven through my town before today and seen the mpg tick upward, only downward. I'm curious how restrictive the stock system is to the aftermarket mufflers. I'll find out next week after a few runs to work to see if I'm finding any real difference. I wasn't expecting it but I'll take it if it's there.

One other comment, the only other thing I was disappointed in was finding cheap pipe clamps included with the kit. Instead of using the supplied U bolt clamps I used a nice stainless strap set I had left over from the Corsa installation I had on my 03 STS (had that system welded together).

Some pics for comparison, excuse the lighting, bad sun angle for the time of day I was working on it.

Update, it was actually pulling pretty hard on the muffler hangers. Going to try some shorter hangers if I can get to Advance Auto before they close for the evening. 1 1/2" stock, going to see if I can find a 3/4" set of hangers. In the meantime, I ended up pulling the hangers off and turning them sideways to see if that bought me any lift, it did.

Stock system from the rear for comparison:
http://i24.photobucket.com/albums/c13/wake96c4/The%20Cars/STS-V/StockExhaust.jpg



Gibson System and the sagging driver's side muffler I'll need a shop to tweak:
http://i24.photobucket.com/albums/c13/wake96c4/The%20Cars/STS-V/GibsonExhaust1.jpg


Gibson system and the protruding tips (not a fan of):
http://i24.photobucket.com/albums/c13/wake96c4/The%20Cars/STS-V/GibsonExhaust2.jpg


Adjusted, still not perfect but getting there.
http://i24.photobucket.com/albums/c13/wake96c4/The%20Cars/STS-V/GibsonExhaustAdjusted.jpg

Dave G
03-10-13, 03:25 AM
I agree. They stick out and hang down. Hmm...

youknooow
03-10-13, 10:33 AM
I'm a fan of how my Gibson tips protrude the bumper.

1BadCadSTS
03-10-13, 11:30 AM
That doesn't look right. My corsa tucks in beautifully that looks like something's aligned improperly.

wake
03-10-13, 01:12 PM
That doesn't look right. My corsa tucks in beautifully that looks like something's aligned improperly.

Corsa always has a perfect fit IMO, I don't think I've ever seen a badly designed system from them.

It isn't aligned properly, the thing is I spent an hour on that side alone and that's the best alignment I could get. The problem appears that the pipe isn't bent quite right in manufacturing which is why I think I'll end up having to go to a muffler shop to have them tweak it a bit. The only adjustments possible are sliding forward and backward and twisting the pipe at the point where it clamps to the stock exhaust.

I'm as far forward as I can go. I contemplated cutting another 1/2" off the stock pipe to see if I could get the muffler slid forward a little more but I don't think I have a lot to work with, I already have to trim the plastic fender liner because the muffler is right up against it and it would also bring the muffler very close to the sway bar bushing. The 3 muffler hangers are lined up correctly and not stretched. It just looks to me like the fit isn't quite right for the driver's side. The passenger side went on in about 5 minutes.

Compared to the stock mufflers these are a much different dimension, the stock mufflers are shorter and fatter while these are more narrow and longer, looks a lot like a Flowmaster muffler. I've seen a picture of the Gibson installed but it was on a regular STS which is a different part number, the STS and the V version have their own dedicated kits so I assumed it would have been designed to work the same way. Who knows though, maybe slightly different car dimension as I believe the V has it's own bumper cover, different than the standard STS.

I'm going to get under it again today and see if there's anything left to tweak.

On a side note, cutting the mufflers off was very easy with one of those chain cutter style tools. I ended up installing a Magnaflow system on my Escalade yesterday and it made very quick work of the 3 cuts I needed to get the stock system out. Fast and clean with no jagged edges that you'd get with a saw.

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I'm a fan of how my Gibson tips protrude the bumper.

Ah, so yours sticks out as well. That answers one question for me. Did you install it yourself, or do you remember if a shop had a hard time getting the alignment correct or required any tweaking?

Ludacrisvp
03-10-13, 02:40 PM
There is a thread about exhaust sound in the regular STS section with talks about the Gibson exhaust might get you more info.

Edit:
http://www.cadillacforums.com/forums/showthread.php?t=252508

wake
03-10-13, 06:55 PM
There is a thread about exhaust sound in the regular STS section with talks about the Gibson exhaust might get you more info.

Edit:
http://www.cadillacforums.com/forums/showthread.php?t=252508

Thanks, interesting read. Gotta love the Corsa vs. anything else discussions. It does appear I was incorrect earlier, Gibson only makes one kit for the STS and it is for the V model. I'm kinda surprised that they would invest the time and resources for such a limited production vehicle. It might be the audio but it does sound a little different on the 4.6L NA versus our 4.4L SC cars.

Well, after another attempt at adjusting the system I was able to get it closer. Still not perfect but much better than what the initial install looked like yesterday. Going to see if I can find some shorter muffler hangers from the auto parts store.

Ludacrisvp
03-10-13, 07:12 PM
Did you keep or remove the resonator?

wake
03-10-13, 07:19 PM
Did you keep or remove the resonator?

Keeping the resonator. I'm still a bit of a kid at heart at 42 but don't want it too wild. LOL

todrules
03-11-13, 12:05 AM
I had the same issue installing a Gibson, the left side sat noticeably lower than the right side. I ended up bending the factory hanger a bit to get it closer. Then of course a month after I installed it, I scored a Corsa system on ebay for a really great price, I must say the Corsa definitely has a better looking fit. I did like the idle sound a bit better of the Gibson, but I definitely like Corsa as well.

wake
03-12-13, 12:37 AM
I had the same issue installing a Gibson, the left side sat noticeably lower than the right side. I ended up bending the factory hanger a bit to get it closer. Then of course a month after I installed it, I scored a Corsa system on ebay for a really great price, I must say the Corsa definitely has a better looking fit. I did like the idle sound a bit better of the Gibson, but I definitely like Corsa as well.

Interesting, so I'm not the only one.

beyerch
03-15-13, 09:34 PM
I agree that I don't like how that looks at the rear end either.

On a separate note, I'm looking for some stock exhaust stuff. Did you keep stock mufflers and did you have to replace the X pipe that is after the cats? Inquiring minds want to know? :)

wake
03-16-13, 12:51 AM
I agree that I don't like how that looks at the rear end either.

On a separate note, I'm looking for some stock exhaust stuff. Did you keep stock mufflers and did you have to replace the X pipe that is after the cats? Inquiring minds want to know? :)

I did but I'm going to hold on to them, if the look doesn't grow on me I might decide later to return it to stock. The Gibson is an axle back system so the stock X pipe stays in place.

youknooow
03-31-13, 08:30 PM
106038

I thinks it compliments the car well.