Custom exhaust design based on other after-market products.
11-08-07, 03:53 PM
#331
So I got one of those infrared thermometers a few weeks ago for testing optimum tire temps and tonight decided to use it for something else. As I stated previously when I first got my secondary cats removed, I notice a resonance around 3300rpm to 3600rpm only when i'm not WOT. I can not figure out where the hell it's coming from. Then I got the crazy idea to measure the temperture of the straight pipes and they are approx 100 degrees cooler than the pipes before and after them. (I'm assuming it's because they are stainless steel) Having a little understanding about exhaust gas velocity I wonder if this temperature variation could cause the resonance that I am hearing. For some reason when the shop removed the cats they also removed all the heat shielding around the exhaust pipe just before the cats and there is no way of putting it back on, so I ordered some DEI exhaust wrap that I'll be putting on the pipes where the OEM exhaust heat shielding was. I'll report back with my findings. Other than this slight resonance the exhaust sounds beautiful.
11-08-07, 06:11 PM
#332
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So I got one of those infrared thermometers a few weeks ago for testing optimum tire temps and tonight decided to use it for something else. As I stated previously when I first got my secondary cats removed, I notice a resonance around 3300rpm to 3600rpm only when i'm not WOT. I can not figure out where the hell it's coming from. Then I got the crazy idea to measure the temperture of the straight pipes and they are approx 100 degrees cooler than the pipes before and after them. (I'm assuming it's because they are stainless steel) Having a little understanding about exhaust gas velocity I wonder if this temperature variation could cause the resonance that I am hearing. For some reason when the shop removed the cats they also removed all the heat shielding around the exhaust pipe just before the cats and there is no way of putting it back on, so I ordered some DEI exhaust wrap that I'll be putting on the pipes where the OEM exhaust heat shielding was. I'll report back with my findings. Other than this slight resonance the exhaust sounds beautiful.
11-08-07, 06:18 PM
#333
Do you have any pics of your full exhaust system? I am getting as many ideas together as possible before I do my custom exhaust with Magnaflow mufflers. Trying to figure out if I want or dont want cats, or to put aftermarket resonators on place of them? I want mainly performance, and a good deep sound.
11-09-07, 06:31 AM
#335
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11-09-07, 07:31 AM
#336
Just wanted to add my custom exhaust... I don't have any pics of it installed. I will try to get some today or tomorrow.
Anyway, I have these mufflers: http://www.magnaflow.com/02product/s...ne=main&id=581
and this X-Pipe: http://www.magnaflow.com/02product/s...ne=main&id=855
I had the 2 rear catalytics (or w/e they are) removed. So only the primary cat's are still in place.
I think the X-Pipe could be better... it's just a stamped piece. I would of loved to get the Burn's x-pipe... but that thing is expensive as hell.
The piping is 2.5" after the primary cats. I'm not sure of any gains. I did got to a 1/8th track, but I don't currently have the slips with me. If I can find them, I will post the results here. I will also be going to a 1/4 mile track soon (November 30th).
Personally, when the car is cold and its getting warmed up... it sounds like a raspy fart can. But once it warm's up... it sounds just awesome. If you are accelerating normally, you can hear it and once you are cruising... you can hardly tell its there.
Anyway, I have these mufflers: http://www.magnaflow.com/02product/s...ne=main&id=581
and this X-Pipe: http://www.magnaflow.com/02product/s...ne=main&id=855
I had the 2 rear catalytics (or w/e they are) removed. So only the primary cat's are still in place.
I think the X-Pipe could be better... it's just a stamped piece. I would of loved to get the Burn's x-pipe... but that thing is expensive as hell.
The piping is 2.5" after the primary cats. I'm not sure of any gains. I did got to a 1/8th track, but I don't currently have the slips with me. If I can find them, I will post the results here. I will also be going to a 1/4 mile track soon (November 30th).
Personally, when the car is cold and its getting warmed up... it sounds like a raspy fart can. But once it warm's up... it sounds just awesome. If you are accelerating normally, you can hear it and once you are cruising... you can hardly tell its there.
11-09-07, 04:22 PM
#337
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Just wanted to add my custom exhaust... I don't have any pics of it installed. I will try to get some today or tomorrow.
Anyway, I have these mufflers: http://www.magnaflow.com/02product/s...ne=main&id=581
and this X-Pipe: http://www.magnaflow.com/02product/s...ne=main&id=855
I had the 2 rear catalytics (or w/e they are) removed. So only the primary cat's are still in place.
I think the X-Pipe could be better... it's just a stamped piece. I would of loved to get the Burn's x-pipe... but that thing is expensive as hell.
The piping is 2.5" after the primary cats. I'm not sure of any gains. I did got to a 1/8th track, but I don't currently have the slips with me. If I can find them, I will post the results here. I will also be going to a 1/4 mile track soon (November 30th).
Personally, when the car is cold and its getting warmed up... it sounds like a raspy fart can. But once it warm's up... it sounds just awesome. If you are accelerating normally, you can hear it and once you are cruising... you can hardly tell its there.
Anyway, I have these mufflers: http://www.magnaflow.com/02product/s...ne=main&id=581
and this X-Pipe: http://www.magnaflow.com/02product/s...ne=main&id=855
I had the 2 rear catalytics (or w/e they are) removed. So only the primary cat's are still in place.
I think the X-Pipe could be better... it's just a stamped piece. I would of loved to get the Burn's x-pipe... but that thing is expensive as hell.
The piping is 2.5" after the primary cats. I'm not sure of any gains. I did got to a 1/8th track, but I don't currently have the slips with me. If I can find them, I will post the results here. I will also be going to a 1/4 mile track soon (November 30th).
Personally, when the car is cold and its getting warmed up... it sounds like a raspy fart can. But once it warm's up... it sounds just awesome. If you are accelerating normally, you can hear it and once you are cruising... you can hardly tell its there.
11-09-07, 05:24 PM
#338
Sounds exactly what I want to do. Do you know Magnaflow has resonators to go in the place of the secondary cats? Or anybody that does? The only reason I ask is that I am sure a lot of exhaust shops will not want to cut out my secondaries, and if I have some aftermarket resonators it will be easier, and maybe help performance as well. Let me know what you think.
Last edited by caymandive; 11-09-07 at 05:37 PM.
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11-09-07, 06:15 PM
#340
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I just ordered two of these 12" resonators to replace my straight pipes where the secondary cats were. I have this slight resonance around 3300rpm only while the engine is under load that probably wouldn't bother most people but man I must be getting old and just won't accept it. I'll let you guys know how the new resonators work out.
11-09-07, 09:46 PM
#342
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11-09-07, 11:07 PM
#343
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^^ yea i wonder which piping our cars work better with? cant there be a good difference in performance based on what size piping you use...? i wonder what the perfect size is
11-09-07, 11:35 PM
#344
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Thats exactly what I am trying to figure out before I buy my magnaflows in a 2.25" or a 2.5". What is the stock diameter?
