Anyone done any REAL exhaust testing?
05-31-2014, 01:43 PM
#41
Le Mans Master
Thread Starter
At one time I was considering installing some 3" chambered mufflers from "Classic Chambered Exhaust" into my Kooks 3" X-Pipe. After that there was no 3" over the axle straight setup similar to the one that Borla makes in 2.5" without going custom bent mandrel. A couple of shops in the Houston area could have done it for me but I didn't pursue because I would not know the sound characteristics until the project was complete. I didn't want a loud drone so I sat back and waited for a manufacturer to make one. Look at the link below, I think it may answer a few questions and have some solutions.
http://classicchambered.com/index.html
I spoke with Corsa when the Extreme C5 system first came out and asked if they would do in 3" and mentioned the interest from the forced induction crowd and they said the 2.5" would handle our needs. Obviously it will flow well for a 2.5" but I was looking for an optimized 3" system. The LG system was an option at the time also but I heard that it had drone and also didn't like the factory style mufflers with all the bends. With a 3" bypass like the Ti-Mod it may work well but I wasn't willing to purchase it, modify it and hope I liked the sound.
Recently a CF member that road races his C6z had a custom muffler system manufactured by Burns Exhaust in 3". Currently in the Autocross/Roadrace section they are trying to put together a group buy. It's possible that Burns could do something similar for the C5 at least for the over the axle part in mandrel 3" but not sure of the mufflers. I still think the 3" straight mufflers from "Classic Chambered Exhaust" installed in a 3" X-Pipe would be the best muffler solution. They come in many lengths which determines how loud it will sound and IMHO are the best "muffled" option I've seen for C5 fitment.
The link to the Burns Exhaust thread on CF:
http://forums.corvetteforum.com/auto...group-buy.html
There seems to be several threads from this one link so it may be a lot of reading.
Link below with pictures seems to be original thread:
http://forums.corvetteforum.com/c6-z...t-exhaust.html
http://classicchambered.com/index.html
I spoke with Corsa when the Extreme C5 system first came out and asked if they would do in 3" and mentioned the interest from the forced induction crowd and they said the 2.5" would handle our needs. Obviously it will flow well for a 2.5" but I was looking for an optimized 3" system. The LG system was an option at the time also but I heard that it had drone and also didn't like the factory style mufflers with all the bends. With a 3" bypass like the Ti-Mod it may work well but I wasn't willing to purchase it, modify it and hope I liked the sound.
Recently a CF member that road races his C6z had a custom muffler system manufactured by Burns Exhaust in 3". Currently in the Autocross/Roadrace section they are trying to put together a group buy. It's possible that Burns could do something similar for the C5 at least for the over the axle part in mandrel 3" but not sure of the mufflers. I still think the 3" straight mufflers from "Classic Chambered Exhaust" installed in a 3" X-Pipe would be the best muffler solution. They come in many lengths which determines how loud it will sound and IMHO are the best "muffled" option I've seen for C5 fitment.
The link to the Burns Exhaust thread on CF:
http://forums.corvetteforum.com/auto...group-buy.html
There seems to be several threads from this one link so it may be a lot of reading.
Link below with pictures seems to be original thread:
http://forums.corvetteforum.com/c6-z...t-exhaust.html
Chambered pipes flow TERRIBLE... I wouldn't go that route... With deal with that BS on the C2 Vettes we have in our group with chambered side pipes.... Small ID and turbulent as hell..
However you did give me a killer idea tho!
Talking about the bypass mod on the stock Ti......
How about doing a bypass mod on my 3" XSP system the same way, however using a 3" bypass pipe with an electric cutout in the bypass on each side...
Cruising around town, close the bypass and force it all thru the muff... At the track, open the cutout and let the exhaust flow thru the bypass straight to the tips...-- we might be on to something with this... It will help with my clearance issues of installing a cutout anywhere else...
I may pursue this... Relatively cheap too... $300 for some Qtp cutouts and $50 to my exhaust guy.... HMMMM
05-31-2014, 04:43 PM
#42
Melting Slicks
Chambered pipes flow TERRIBLE... I wouldn't go that route... With deal with that BS on the C2 Vettes we have in our group with chambered side pipes.... Small ID and turbulent as hell..
However you did give me a killer idea tho!
Talking about the bypass mod on the stock Ti......
How about doing a bypass mod on my 3" XSP system the same way, however using a 3" bypass pipe with an electric cutout in the bypass on each side...
Cruising around town, close the bypass and force it all thru the muff... At the track, open the cutout and let the exhaust flow thru the bypass straight to the tips...-- we might be on to something with this... It will help with my clearance issues of installing a cutout anywhere else...
I may pursue this... Relatively cheap too... $300 for some Qtp cutouts and $50 to my exhaust guy.... HMMMM
However you did give me a killer idea tho!
Talking about the bypass mod on the stock Ti......
How about doing a bypass mod on my 3" XSP system the same way, however using a 3" bypass pipe with an electric cutout in the bypass on each side...
Cruising around town, close the bypass and force it all thru the muff... At the track, open the cutout and let the exhaust flow thru the bypass straight to the tips...-- we might be on to something with this... It will help with my clearance issues of installing a cutout anywhere else...
I may pursue this... Relatively cheap too... $300 for some Qtp cutouts and $50 to my exhaust guy.... HMMMM
Sounds like a cool idea to me!
I love the way the xsp sounds and with an electric cutout/bypass it would be awesome!
05-31-2014, 09:42 PM
#43
Drifting
When I was 638rwhp the cutouts added 13rwhp on the dyno but the car felt a little sluggish in lower rpms and came on harder up top. Now I'm 800+rwhp and I added the Callaway DoubleD exhaust. You can tell there is not as much back pressure as the TI exhaust for sure. I came to conclusion that my car (seat of the pants) runs better with a little bit of back pressure. Plus I always have the cutouts on stand by. I'm also running LG pro's and 3" xpipe no cats.
06-01-2014, 10:28 AM
#44
Le Mans Master
Thread Starter
I'm going to try something similar to this...Only I'll use a 3" bypass pipe and it will come off the over the axle pipe straight off the corner so there will be no bend to the tips..... Then I'm going to oval the bypass pipe where it ties into the tips so it will feed both tips on each side, making the tip a full 3" outlet...
I'll be shutting my car down here in a few weeks to do some repairs, some mods and I'll do the bypass mod with the electric cutouts at the same time.... Then I will dyno test it to see if the cutouts helped or not.....If not, its not a major loss....(<$500)...
I'm still open to suggestions and any other exhaust info anyone has...
06-01-2014, 11:25 AM
#45
Team Owner
Here's a cool setup! C6 ZR1 Full 3" Factory Exhaust on C5 Corvette and 3" B&B Fusion - YouTube
Why the C5 Z06 TI exhaust flows so well is still beyond me - that is why I had to cut one open, and especially since it had not been done before that (or that I could find anywhere)
I really like (In my Youtube Video above) 3" B&B Fusions with the full factory 3" C6 ZR1 Exhaust manifolds, cats, xpipe
It is proven to make real good HP, as it is in my case - I would of stayed with LT headers etc, if it were not for California smog regs!
Either way I do love the sound of my new set-up and performance!
Thanks,Matt
06-01-2014, 11:28 AM
#46
Team Owner
I'm going to try something similar to this...Only I'll use a 3" bypass pipe and it will come off the over the axle pipe straight off the corner so there will be no bend to the tips..... Then I'm going to oval the bypass pipe where it ties into the tips so it will feed both tips on each side, making the tip a full 3" outlet...
I'll be shutting my car down here in a few weeks to do some repairs, some mods and I'll do the bypass mod with the electric cutouts at the same time.... Then I will dyno test it to see if the cutouts helped or not.....If not, its not a major loss....(<$500)...
I'm still open to suggestions and any other exhaust info anyone has...
Thanks,Matt
06-01-2014, 03:08 PM
#47
Le Mans Master
plenty of people have done the cutout in the muffler bypass & been happy with it. personally, i'd recommend DMH cutouts - less problems i've heard about & a longer warranty. those're the ones i've got - almost 3 years & running strong.
06-01-2014, 05:30 PM
#48
I have GHL bullets with two cut outs, each cut out is right before the bend to go up over the axel, I have a turbo car but I couldn't give you results yet. Some day if I ever get time to tune it I will. When I get back in town I can post Picts.
06-01-2014, 05:38 PM
#49
06-01-2014, 08:51 PM
#50
Le Mans Master
Interesting design on the Corsa extreme.. Pretty much straight pipe with just a small "draw off" into a dead headed muffler to knock the edge off the drone.. If this was a 3" system, they may be on to something..
I'm gonna contact PYPEs about possibly building a system for a C5, setup the way I want it... Or I may build my own using the 3" cat back I have and just revamping it before the muffs... Gonna research this for a while...
Ideally, I'd like to Dyno mine as it sits with the XSP exhaust, then pull the mufflers off and see if it picks up power...if it does, then I know I need to do something.. If not, I'll let it ride.. The problem is I have my mufflers welded on so its not gonna be an easy task to yank em off and throw em back on.... Not to mention the pipes falling down over the axles when the muffs are off.
06-01-2014, 09:04 PM
#51
Burning Brakes
I'm going to try something similar to this...Only I'll use a 3" bypass pipe and it will come off the over the axle pipe straight off the corner so there will be no bend to the tips..... Then I'm going to oval the bypass pipe where it ties into the tips so it will feed both tips on each side, making the tip a full 3" outlet...
I'll be shutting my car down here in a few weeks to do some repairs, some mods and I'll do the bypass mod with the electric cutouts at the same time.... Then I will dyno test it to see if the cutouts helped or not.....If not, its not a major loss....(<$500)...
I'm still open to suggestions and any other exhaust info anyone has...
06-02-2014, 10:30 PM
#52
Le Mans Master
Thread Starter
Well after an extremely long day... My exhaust experiment/modding is done.... Here is the completed system..
Had to cut the trunk, no way around it with 3" pipes... I'm going to build a flat trunk floor out of aluminum for it.....
Starting "Y" ing into the axle pipe... I really wanted to tap right into the arch of the bend more, but it would have made it a lot harder to get a straight shot to the tip... This is what we ended up with...3" Y, ovaled...then cut and ovaled to hole to get as much flow as I can..
Pretty decent size holes in there after we ovaled them... I realize this is still not the OPTIMUM position for max flow to the cutout...Really need a way bigger "V" cut into the axle pipe....But after looking at everything and how hard it was gonna be to weld it closer to the cradle, we went this route.... I would imagine we are getting 60-75% flow through the cutout when its open..
Yes I need to go back and clean up the entire system, rear bumper cover etc etc...as well as tape off/paint all the welds...I just ran out of time today and wanted to get some pics up. I know its filthy under there...It will get resolved..
I think it looks sick without the big trunk tub down there.... Will be much easier to pull the drive train too..
And a vid...
Initially the cutouts are closed.... Then open, then closed....I think you'll hear the difference...
Maybe in a month or so, I'll get it on the dyno and see if all of this effort and money was worth anything or not.....
Had to cut the trunk, no way around it with 3" pipes... I'm going to build a flat trunk floor out of aluminum for it.....
Starting "Y" ing into the axle pipe... I really wanted to tap right into the arch of the bend more, but it would have made it a lot harder to get a straight shot to the tip... This is what we ended up with...3" Y, ovaled...then cut and ovaled to hole to get as much flow as I can..
Pretty decent size holes in there after we ovaled them... I realize this is still not the OPTIMUM position for max flow to the cutout...Really need a way bigger "V" cut into the axle pipe....But after looking at everything and how hard it was gonna be to weld it closer to the cradle, we went this route.... I would imagine we are getting 60-75% flow through the cutout when its open..
Yes I need to go back and clean up the entire system, rear bumper cover etc etc...as well as tape off/paint all the welds...I just ran out of time today and wanted to get some pics up. I know its filthy under there...It will get resolved..
I think it looks sick without the big trunk tub down there.... Will be much easier to pull the drive train too..
And a vid...
Initially the cutouts are closed.... Then open, then closed....I think you'll hear the difference...
Maybe in a month or so, I'll get it on the dyno and see if all of this effort and money was worth anything or not.....
Last edited by ajrothm; 06-02-2014 at 10:34 PM.
06-02-2014, 11:34 PM
#53
Team Owner
Member Since: Jan 2007
Location: cookeville tennessee
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^^^ Buddy that sounds great dont see how you will not get better hp & tq out of her. I say at least 20 more..
I know you will please post it when you get her back on the dyno...
I know you will please post it when you get her back on the dyno...
Last edited by robert miller; 06-02-2014 at 11:37 PM.
06-02-2014, 11:55 PM
#55
Le Mans Master
Thread Starter
Couple other interesting pics...
So my 3" XS Power cat back, is actually 3" in, 2.5" out into the dual tips... Well that 2.5" appears to start from an open chamber at the end of the muff, just like the stock Ti muffs... As best as I could tell... Here is a pic of the outlet pipe inside the muffler after we cut the dual tip pipe off... We ended up building a single tip pipe for the muff.
My ARH 3" mid pipe/x pipe has this nice little bottle neck down to 2.5 ish" right at the flange...
This is looking through the cutout pipe where it "Y"s into the axle pipe....We slash cut/ovaled that pipe and I cut the oval hole in the axle pipe as big as I could to get as much flow before the bend as I could get....(I know its not perfect)
Left side
Seems like some decent size holes, maybe not in the highest pressure area to draw off from but....Definitely gets some decent flow.. Hard as hell to grind that crap out to open it up a lot....grinder angles are hard to get going through a 3" flange....
Ironically, the car is a little quieter, but a little deeper with the single tip coming off the muffler as opposed to dual tips coming off the muff.. But if I crack open the cutout maybe 1/8", it sounds pretty nasty at idle.... Open it any more then that and it sounds like a straight pipe farm truck...(as seen in my vid)...Only time it will ever drive like that is at the track.
So my 3" XS Power cat back, is actually 3" in, 2.5" out into the dual tips... Well that 2.5" appears to start from an open chamber at the end of the muff, just like the stock Ti muffs... As best as I could tell... Here is a pic of the outlet pipe inside the muffler after we cut the dual tip pipe off... We ended up building a single tip pipe for the muff.
My ARH 3" mid pipe/x pipe has this nice little bottle neck down to 2.5 ish" right at the flange...
This is looking through the cutout pipe where it "Y"s into the axle pipe....We slash cut/ovaled that pipe and I cut the oval hole in the axle pipe as big as I could to get as much flow before the bend as I could get....(I know its not perfect)
Left side
Seems like some decent size holes, maybe not in the highest pressure area to draw off from but....Definitely gets some decent flow.. Hard as hell to grind that crap out to open it up a lot....grinder angles are hard to get going through a 3" flange....
Ironically, the car is a little quieter, but a little deeper with the single tip coming off the muffler as opposed to dual tips coming off the muff.. But if I crack open the cutout maybe 1/8", it sounds pretty nasty at idle.... Open it any more then that and it sounds like a straight pipe farm truck...(as seen in my vid)...Only time it will ever drive like that is at the track.
06-02-2014, 11:58 PM
#57
Le Mans Master
06-03-2014, 08:31 AM
#60
Tech Contributor
I love it! It's always nice to know there are others out there that are at least close to equally as crazy as you are. Thanks for the reminder, it's so comforting! 
That's what this forum is all about IMO.
In for the results. I might have to add this one to my bucket list.
That's what this forum is all about IMO. In for the results. I might have to add this one to my bucket list.