3" Corvette Exhaust?
Thread Starter
Joined: Apr 2009
Posts: 6,717
Likes: 24
From: Lafayette, LA
First I want to say we have sent in all our sponsor stuff so mods please don't delete this. Having said that here is my standing. For the 3'' exhaust they all fit like crap to be honest. I have the lg big 3 on my personal high compression c5 and while I absolutely love how it sounds it is without a doubt one of the worst fitting exhaust I have ever installed. The xs is not really any better to be honest. You won't see really any gains unless your max effort like me so save the headache and do a corsa, magnaflow, or whatever brand you like the sound of. Now for the headers we have done tons of testing on c6's with the pfadt's and they flat out perform!! Others mentioned the whole sales price thing and they are correct, pfadt is very serious about the minimum price you can sell their items for because they 1 want to protect their product in terms of value and 2 it keeps dealers from doing the bidding wars deal. Pfadt's truly are the cream of the crop and when you see a set you will quickly realize why. Don't get me wrong kook's and arh are awesome too but no one does v-band flanges except for pfadt 
Do the Phadt's have a bung already installed for a wideband?
Don't agree with sponsors not being able to run sales though. Sales are what drive business... Especially during tax time.
Unless I find a used Big 3, the catback will probably be a XSPower 3". I've read good reviews on them. Lots of folks happy with fit, finish and sound.
I have a 2.5" Corsa now, but I'll be damned if I stay with a 2.5" anything.
Just saw your pm, I sold my XS power exhaust because Im going to try the big 3. The xs sounded like corsa but better like a little deeper tone and the setup I had made it rediculusly not stealthy. The xs flange mates to the stock flange becuase the 3" flange has slotted holes for the bolts so it will fit 2.5" or 3" flange bolt patterns. My biggest complaint was that the xs tip pipe was closer to 2.5" od. Not to many know that and I found out after the fact
I asked why and was told it helped lower interior drone to which I called bs.
Xs power pros: sounds great, cheaper
Xs power cons: didnt like the lack of adjustability and tip alignment, smaller od tip pipe, less flow its a hollow resonator muffler so no continuous perforated pipe
Big 3 pros: all 3" pipe, comes with new flanges to make my necked down kooks mid pipe flange a full and 3" at the flange, complete adjustability, mellow if thats your thing or not (there are ways to fix that), better flow with continuous perforated mat wrapped muffler tubes.
Big 3 cons: cost, had bad clamps in the past (pypes clamps fix that), mellow (but that can be changed lol).
My .2 cents
I asked why and was told it helped lower interior drone to which I called bs.Xs power pros: sounds great, cheaper
Xs power cons: didnt like the lack of adjustability and tip alignment, smaller od tip pipe, less flow its a hollow resonator muffler so no continuous perforated pipe
Big 3 pros: all 3" pipe, comes with new flanges to make my necked down kooks mid pipe flange a full and 3" at the flange, complete adjustability, mellow if thats your thing or not (there are ways to fix that), better flow with continuous perforated mat wrapped muffler tubes.
Big 3 cons: cost, had bad clamps in the past (pypes clamps fix that), mellow (but that can be changed lol).
My .2 cents
Last edited by jobe_ls1; Oct 28, 2013 at 09:56 PM.
Thread Starter
Joined: Apr 2009
Posts: 6,717
Likes: 24
From: Lafayette, LA
I'm the owner of Cordes Performance Racing we are a big lsx shop in AZ www.cordesperformanceracing.com www.facebook.com/cordesperformanceracing joe@cordesperformanceracing.com The pfadt's do have a bung for a wideband. Pfadt does offer sales from time to time but it's when you see the huge bidding wars and the parts value gets tanked by hundreds of dollars is where the issue lies. They don't want that and frankly don't need to as they build a superior product and understand the shops that sell it need to make some $ to keep the lights on.
By the way, welcome as a Sponsor, Joe!!
Thread Starter
Joined: Apr 2009
Posts: 6,717
Likes: 24
From: Lafayette, LA
Just saw your pm, I sold my XS power exhaust because Im going to try the big 3. The xs sounded like corsa but better like a little deeper tone and the setup I had made it rediculusly not stealthy. The xs flange mates to the stock flange becuase the 3" flange has slotted holes for the bolts so it will fit 2.5" or 3" flange bolt patterns. My biggest complaint was that the xs tip pipe was closer to 2.5" od. Not to many know that and I found out after the fact I asked why and was told it helped lower interior drone to which I called bs.
Xs power pros: sounds great, cheaper
Xs power cons: didnt like the lack of adjustability and tip alignment, smaller od tip pipe, less flow its a hollow resonator muffler so no continuous perforated pipe
Big 3 pros: all 3" pipe, comes with new flanges to make my necked down kooks mid pipe flange a full and 3" at the flange, complete adjustability, mellow if thats your thing or not (there are ways to fix that), better flow with continuous perforated mat wrapped muffler tubes.
Big 3 cons: cost, had bad clamps in the past (pypes clamps fix that), mellow (but that can be changed lol).
My .2 cents
I asked why and was told it helped lower interior drone to which I called bs.Xs power pros: sounds great, cheaper
Xs power cons: didnt like the lack of adjustability and tip alignment, smaller od tip pipe, less flow its a hollow resonator muffler so no continuous perforated pipe
Big 3 pros: all 3" pipe, comes with new flanges to make my necked down kooks mid pipe flange a full and 3" at the flange, complete adjustability, mellow if thats your thing or not (there are ways to fix that), better flow with continuous perforated mat wrapped muffler tubes.
Big 3 cons: cost, had bad clamps in the past (pypes clamps fix that), mellow (but that can be changed lol).
My .2 cents
I want it loud. Not stupid, but not Magnaflow FBody quiet either.
I'm curious to know what the inside of each muffler actually looks like. Apparently Stainless Works has a 3" Turbo Catback as well. They have pics on their site of what the muffler looks like on the inside. Curious though on a Vette Application.
This thread got me curious, so I looked at Kooks website. I find it odd that they make a full 3" true dual system for the F-body but not the C5. Why?
I'm also surprised to see the 1-3/4 vs 1-7/8 debate again. I thought it was proven that even on a stock LS1, 1-7/8 gain you more power everywhere and therefore there is no reason to use 1-3/4 unless you find some really cheap. You did decide to go with 1-7/8" primaries, correct?
I'm also surprised to see the 1-3/4 vs 1-7/8 debate again. I thought it was proven that even on a stock LS1, 1-7/8 gain you more power everywhere and therefore there is no reason to use 1-3/4 unless you find some really cheap. You did decide to go with 1-7/8" primaries, correct?
Thread Starter
Joined: Apr 2009
Posts: 6,717
Likes: 24
From: Lafayette, LA
This thread got me curious, so I looked at Kooks website. I find it odd that they make a full 3" true dual system for the F-body but not the C5. Why? I'm also surprised to see the 1-3/4 vs 1-7/8 debate again. I thought it was proven that even on a stock LS1, 1-7/8 gain you more power everywhere and therefore there is no reason to use 1-3/4 unless you find some really cheap. You did decide to go with 1-7/8" primaries, correct?
I've been talking to Kooks. They have no plans as of now for a C5 system, but said they can do a custom one, starting at 1850.
I'd do the ARH headers. The build quality is great.
And remember what I said about primary design?
Power from headers comes from 4 variables:
1) Length of the collector and type (HVMC, stamped, etc)
2) Primary size
3) Primary length
4) Exhaust valve size
LGs put up big numbers for years because they have a much longer length primary (and if you read Vizard's book on exhausts, a 346 is ideally equipped with a 32" long primary that is 1.75" in size for upto 7000 RPM). When you move to a 1.875" primary that is 24" long, it is much better than a 1.75" primary that is also 24" long. Which is why you see absolutely no downside in the F-Body world.
The other thing to remember is the collector length/type. I've seen it with Kooks here. The older style Kooks vs the newer HVMC collectors (ala ARH or QTP), which are also longer, walk the stamped collectors at all RPMs. The LG Pros had really nice HVMC on them before Kooks started doing it or ARH came into the picture. So LG had a few years of producing a much better designed header than the rest of the industry from say 01-05 and that's where the folks on CF are stuck.
And one other thing: LG routinely paired their headers with AFR 205s. Guess what the 205s have? 1.60" exhaust valves and very large, high flowing exhaust ports. When I've talked to vendors about this, the testing shows the 1.60" valve in the AFR heads tends to perform better with a 1-3/4" header, especially one that is 32" with a tuned collector. Almost all other heads show better power from 1-7/8" headers with 1.55 or 1.575" exhaust valves. The thinking is the larger exhaust port/valve has less velocity, so the tuned LG headers help scavenge it more efficiently.
Just another piece of info to consider. But the old LG G5X3/AFR 205 combo with LG Headers and a FAST 90 was good for 480-500rwhp with 440-450tq all the time.
And remember what I said about primary design?
Power from headers comes from 4 variables:
1) Length of the collector and type (HVMC, stamped, etc)
2) Primary size
3) Primary length
4) Exhaust valve size
LGs put up big numbers for years because they have a much longer length primary (and if you read Vizard's book on exhausts, a 346 is ideally equipped with a 32" long primary that is 1.75" in size for upto 7000 RPM). When you move to a 1.875" primary that is 24" long, it is much better than a 1.75" primary that is also 24" long. Which is why you see absolutely no downside in the F-Body world.
The other thing to remember is the collector length/type. I've seen it with Kooks here. The older style Kooks vs the newer HVMC collectors (ala ARH or QTP), which are also longer, walk the stamped collectors at all RPMs. The LG Pros had really nice HVMC on them before Kooks started doing it or ARH came into the picture. So LG had a few years of producing a much better designed header than the rest of the industry from say 01-05 and that's where the folks on CF are stuck.
And one other thing: LG routinely paired their headers with AFR 205s. Guess what the 205s have? 1.60" exhaust valves and very large, high flowing exhaust ports. When I've talked to vendors about this, the testing shows the 1.60" valve in the AFR heads tends to perform better with a 1-3/4" header, especially one that is 32" with a tuned collector. Almost all other heads show better power from 1-7/8" headers with 1.55 or 1.575" exhaust valves. The thinking is the larger exhaust port/valve has less velocity, so the tuned LG headers help scavenge it more efficiently.
Just another piece of info to consider. But the old LG G5X3/AFR 205 combo with LG Headers and a FAST 90 was good for 480-500rwhp with 440-450tq all the time.
Thread Starter
Joined: Apr 2009
Posts: 6,717
Likes: 24
From: Lafayette, LA
Certainly good points, and things to take into consideration.
After talking to several people, vendors, everyone is saying the 2.5" Corsa I have will be plenty. They've even went on to say that switching to a 3" wouldn't even show any gains. Just strikes me as odd.
I guess the hell with it. I'll get either ARH 1 7/8" or the Phadt 1 7/8" that step to a 2.1" secondary. 3" off road X, and mate it to my Corsa and see how it is.
After talking to several people, vendors, everyone is saying the 2.5" Corsa I have will be plenty. They've even went on to say that switching to a 3" wouldn't even show any gains. Just strikes me as odd.
I guess the hell with it. I'll get either ARH 1 7/8" or the Phadt 1 7/8" that step to a 2.1" secondary. 3" off road X, and mate it to my Corsa and see how it is.
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Verdad Gallardo This post in itself has me torn now. I wanted to go with the XSPower, but I simply can't grasp the concept of making, and advertising, a 3" exhaust, only to lop it off to 2.5" on the exit pipes out of the muffler. What the hell? What have the sellers of this product had to say about that?
I want it loud. Not stupid, but not Magnaflow FBody quiet either.
I'm curious to know what the inside of each muffler actually looks like. Apparently Stainless Works has a 3" Turbo Catback as well. They have pics on their site of what the muffler looks like on the inside. Curious though on a Vette Application.
I want it loud. Not stupid, but not Magnaflow FBody quiet either.
I'm curious to know what the inside of each muffler actually looks like. Apparently Stainless Works has a 3" Turbo Catback as well. They have pics on their site of what the muffler looks like on the inside. Curious though on a Vette Application.
The stainless works 3" is the same as the LG big 3".
Check out Matt's videos here and a quick zip in a 416 here
Certainly good points, and things to take into consideration.
After talking to several people, vendors, everyone is saying the 2.5" Corsa I have will be plenty. They've even went on to say that switching to a 3" wouldn't even show any gains. Just strikes me as odd.
I guess the hell with it. I'll get either ARH 1 7/8" or the Phadt 1 7/8" that step to a 2.1" secondary. 3" off road X, and mate it to my Corsa and see how it is.
After talking to several people, vendors, everyone is saying the 2.5" Corsa I have will be plenty. They've even went on to say that switching to a 3" wouldn't even show any gains. Just strikes me as odd.
I guess the hell with it. I'll get either ARH 1 7/8" or the Phadt 1 7/8" that step to a 2.1" secondary. 3" off road X, and mate it to my Corsa and see how it is.
Sorry I'm late to the party, here are my results from years ago fwiw...
http://forums.corvetteforum.com/perf...s-results.html
http://forums.corvetteforum.com/perf...s-results.html
Not sure if Huron still sells these or if the "back order" is still in effect....but
the set I got fit perfect and definitely woke up the Corsa CB (loudness).
FWIW he markets them as a 1 3/4" primary but the dial calipers showed a
1.90" OD which points to roughly 1 3/4 ID. The primary pipes are shorter
however the merge collector w/spike is awefully nice and the X is right off
the collectors which I feel helps since the gasses are hotter and velocity is up
compared to my previous Corsa X which was toward the back of the exhaust.
http://shop.huronspeedproducts.com/X...-XSPC5LTHS.htm
They have not rusted and simply have a nice gold colored tint to them after
2 years of heat cycles.
Lastly Dr does your C5 have the 4 cat set-up ?? Mine did which could explain
the quietness.
the set I got fit perfect and definitely woke up the Corsa CB (loudness).
FWIW he markets them as a 1 3/4" primary but the dial calipers showed a
1.90" OD which points to roughly 1 3/4 ID. The primary pipes are shorter
however the merge collector w/spike is awefully nice and the X is right off
the collectors which I feel helps since the gasses are hotter and velocity is up
compared to my previous Corsa X which was toward the back of the exhaust.
http://shop.huronspeedproducts.com/X...-XSPC5LTHS.htm
They have not rusted and simply have a nice gold colored tint to them after
2 years of heat cycles.
Lastly Dr does your C5 have the 4 cat set-up ?? Mine did which could explain
the quietness.
Thread Starter
Joined: Apr 2009
Posts: 6,717
Likes: 24
From: Lafayette, LA
Not sure if Huron still sells these or if the "back order" is still in effect....but the set I got fit perfect and definitely woke up the Corsa CB (loudness). FWIW he markets them as a 1 3/4" primary but the dial calipers showed a 1.90" OD which points to roughly 1 3/4 ID. The primary pipes are shorter however the merge collector w/spike is awefully nice and the X is right off the collectors which I feel helps since the gasses are hotter and velocity is up compared to my previous Corsa X which was toward the back of the exhaust. http://shop.huronspeedproducts.com/X...-XSPC5LTHS.htm They have not rusted and simply have a nice gold colored tint to them after 2 years of heat cycles. Lastly Dr does your C5 have the 4 cat set-up ?? Mine did which could explain the quietness.
My wife bought me some 67" Race Ramps. Still can't drive on them forwards. Have to back on to them.
Running to Home Depot for a run of 2x12 and a can of plasti-dip for the rear valence.
TECH Junkie
Joined: Dec 2005
Posts: 3,092
Likes: 11
Edit: I am running 1.75" to 1.875" stepped headers.
I'm not sure how to quantify my swap gains but after removing my BBK
shorties, 4 cats, and Corsa X (2.5") and installing the XS stuff w/3" cats....
NO retune....it dropped from 12.29 at 116.7 to 11.87 at 119.85....and the
Corsa has a much louder bark. I'm not trying to talk you outta the 3" CB
but perhaps pick your header set-up first and know that a cam and blower
will be another step louder after that.
shorties, 4 cats, and Corsa X (2.5") and installing the XS stuff w/3" cats....
NO retune....it dropped from 12.29 at 116.7 to 11.87 at 119.85....and the
Corsa has a much louder bark. I'm not trying to talk you outta the 3" CB
but perhaps pick your header set-up first and know that a cam and blower
will be another step louder after that.
Thread Starter
Joined: Apr 2009
Posts: 6,717
Likes: 24
From: Lafayette, LA
I'm not sure how to quantify my swap gains but after removing my BBK shorties, 4 cats, and Corsa X (2.5") and installing the XS stuff w/3" cats.... NO retune....it dropped from 12.29 at 116.7 to 11.87 at 119.85....and the Corsa has a much louder bark. I'm not trying to talk you outta the 3" CB but perhaps pick your header set-up first and know that a cam and blower will be another step louder after that.
The blower, barring some insane bonus, or someone going 6ft under, is a ways off as of yet. I really like NA and plan to camp in that department for a while yet.
6ft under was a joke, guys, lol
