G8 Exhaust on Caprice?

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lsxJERRY
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Location: NW Indiana

G8 Exhaust on Caprice?

Post by lsxJERRY »

So I've been wanting to do the exhaust on my car, more or less get it redone because it drones terribly.

Problem is I recently started going back to school and money is tight. I found a G8 exhaust on Craigslist for $125 obo and from my research the G8 exhaust is 2.5'' diameter from the cats to the resonator, resonator to mid muffler its 2.25", after that it's 2.5'' again.

This is where I got that info from: G8 Board

Now looking into it, the exhaust for sale looks like a GXP exhaust.

Exhaust for sale:
Image

Exhaust comparison found on Google Images:
Image

Info about this exhaust seems to be inaccurate, but if it's 2.5" at that price, I'm sure it's a good budget exhaust if you modify the mid section. I'm looking to just change the mid muffler and resonators to keep it quiet keeping the stock muffler and just extend the tips.

Anyone know the diameter size?
Does the diameter differ from the Caprice size?
and... what material is it? The guy says it's stainless but i doubt it. Mine on the car is already rusting away on the axle back so might not be worth modifying it again.
CrashTestDummy
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Re: G8 Exhaust on Caprice?

Post by CrashTestDummy »

If it's a stock G8 exhaust system, it'll be stainless. The exhaust system is part of the emissions system, so has to be good for 100K miles. Most OEM exhaust systems these days are stainless because of that. Not all stainless is non-magnetic, and not all stainless will be completely rust-free. It depends on the alloy.
Gene Beaird,
Pearland, Texas
2012 Caprice 9C1
1992 B4C 1LE Camaro
2018 Tahoe PPV (her car)
1995 DGGM Impala SS
1985 Firebird - 310 LS1 C Prepared autocross car.
1980 Bluebird Wanderlodge
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lsxJERRY
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Re: G8 Exhaust on Caprice?

Post by lsxJERRY »

CrashTestDummy wrote:If it's a stock G8 exhaust system, it'll be stainless. The exhaust system is part of the emissions system, so has to be good for 100K miles. Most OEM exhaust systems these days are stainless because of that. Not all stainless is non-magnetic, and not all stainless will be completely rust-free. It depends on the alloy.
Good to know, my exhaust system was hacked up by a local shop and when I was under it, the flexpipes in back were pretty bad and starting to rust. My advice never go to a cheap exhaust shop, they didn't even weld the tips right.

Have any info that can back up exhaust diameter?
CrashTestDummy
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Re: G8 Exhaust on Caprice?

Post by CrashTestDummy »

I have nothing. It looks like, though, from the picture, that the G8 GT exhaust bells out at the rear muffler connection, and they use the same muffler between the GT and GXP. All the axle-back systems I'm seeing for the G8 are 2.5", and they show them to fit V6/V8 G8s, GTs and GXPs. So on a stock GT exhaust system it may be 2" or 2-1/4" to the rear mufflers, then goes to 2.5".
Gene Beaird,
Pearland, Texas
2012 Caprice 9C1
1992 B4C 1LE Camaro
2018 Tahoe PPV (her car)
1995 DGGM Impala SS
1985 Firebird - 310 LS1 C Prepared autocross car.
1980 Bluebird Wanderlodge
And some others
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xcidmigs
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Re: G8 Exhaust on Caprice?

Post by xcidmigs »

That one in the top pic looks pretty similar to the stock camaro SS exhaust which is for the same motor and is 2 1/2" low grade stainless with similar small resonators and a single larger muffler at the rear. I paid $100 for that also on a clist deal, so i would say go for it especially if you plan to cut it up anyway. On the camaro exhaust there is a pinch point in the factory front section but the rest is very smooth and could be attached to the stock PPV mufflers with some adapter pieces. The caprice stuff is definately 2 1/4" and necks down to 2" at some parts. That said I have yet to do it since I'm under warrant for a few more months.
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lsxJERRY
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Re: G8 Exhaust on Caprice?

Post by lsxJERRY »

So I found someone who is going to redo my exhaust for $100, i'm ordering parts for $190, so a total of $290.
Should get the parts Saturday and maybe take it in Monday.
He's also gonna fix the rusted rear section.

My current setup:
Stock headers
Stock catalytic converters
Deleted "pup cats" (I honestly have no idea what they're called)
Deleted mid muffler
Deleted resonators
X-pipe & straight pipes
Stock mufflers
Ugly tips

This is what the underside of a Caprice looks like after 160k miles up in the Great Lakes
Image
Image

I ordered (2) new Dynomax Race Bullets, part# 24215
Flowmaster dual tips part# 15389 & 15390

Resonators are 12", will post up videos of before and after.
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Raunchtastic
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Re: G8 Exhaust on Caprice?

Post by Raunchtastic »

Any update on this? Exhaust will be my next job, as I seem to just be chasing leak after leak and the cabin gets a stench when idling... even if I didn't eat at Taco Bell.
-----------------------------------------------------------
2012 Chevrolet Caprice "The Daily"
1992 Chevrolet Camaro RS 25th anniversary "The Wannabe Racecar"
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lsxJERRY
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Location: NW Indiana

Re: G8 Exhaust on Caprice?

Post by lsxJERRY »

Raunchtastic wrote:Any update on this? Exhaust will be my next job, as I seem to just be chasing leak after leak and the cabin gets a stench when idling... even if I didn't eat at Taco Bell.
I ended up installing a Solo Mach Cat back exhaust kit and had it lengthened to fit the Caprice.
Image
Image

Hear it here:
https://www.youtube.com/watch?v=dPcacKXNfTw" onclick="window.open(this.href);return false;
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