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Duals under a single exhaust car

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Old 12-01-2009 | 09:15 AM
  #16  
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Originally Posted by Chuck Schreiber
Rod, Landsteer,
Nice job!

Rod, did you see some good hp gains with your setup??

CapeCod, how bout your setup, noticeable gains?
I've thought about something like this for the 79, but not sure if the low power 220horse US motor will benefit that much. I'm sure the 300hp Euro really wakes up to exhaust mods!!


Don't really know, except it "seems" faster. I have since put in an H pipe, small cats and S4 mid mufflers instead of the aftermarket. They were a little loud, but the S4 mufflers are just perfect. Love the sound!!! I put heat shields on the mufflers and it has all worked out fine.

Good luck!!

Rod
Old 12-01-2009 | 09:44 AM
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When building up my 1986.5 track car, I took away the dual pipe set up and went with a custom Y pipe from MSDS headers to a custom 3.5 inch single exhaust and a single Magnaflow muffler. The engine was stock and at the track it felt and sounded great. Many people commented how cool the V8 sounded and I truly believe mixing the exhaust into a single pipe helps to change the sound of our V8s. At high RPMs it just howled and some said it "raised the hair on the back of my neck." This from corner workers and onlookers around the track.

From the research I read up on before going with a single pipe setup, I found that a single 3" pipe will flow better than a dual 2.5 inch exhaust system due to parasitic drag of the dual pipe's inner walls given our motor's HP ranges. I went with a 3.5 " system since I was planning on upgrading the power a bit in the future. I never noticed a loss of "grunt" at the lower RPM ranges on the track.

Saving some weight by going to a clean single pipe system was also what I wanted.

Cheers,
Old 12-01-2009 | 01:39 PM
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Yes ! " I truly believe mixing the exhaust into a single pipe helps to change the sound of our V8s. At high RPMs it just howled and some said it "raised the hair on the back of my neck." This from corner workers and onlookers around the track." Most V-8 engines have an irregular firing order an pop off two cylinders on each bank one after the other which is why dual exhaust systems (no x pipe) sound like a V-8. The common exception is Ferrari which uses a flat crankshaft and runs the engine as two 4 cylinders. The single pipe exhaust puts the pulses all together and eliminates the typical Ford Chevy v-8 dual exhaust sound making it SOUND smoother and more like high RPM. Running a loud single exhaust on ANY normal V-8 gives a more sports car sound. Look up 180 degree headers if you want to see how to really even out the pulses
Old 12-01-2009 | 02:25 PM
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Originally Posted by danglerb
Smaller pipe is only a restriction when the flow rate is high, as in the combination of high rpm and WOT. With lower rpm a smaller pipe might actually be much closer to an ideal size for the flow, supporting higher velocities and better scavenging. Heat rise could actually be the smaller pipe creating more power at lower rpms, like 3k vs 5k.
Man that's a nice political answer. Writing much without saing anything at all.

There is such a thing as too big of a pipe for and engine but, to say smaller is only restrictive when the flow is high. Is like saying the sky is bue.
Old 12-01-2009 | 02:40 PM
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Is the sky blue ? I've been in L A so long I thought it was brown.....Besides we ALL KNOW bigger is better.
Old 12-01-2009 | 02:46 PM
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Originally Posted by James Bailey
Is the sky blue ? I've been in L A so long I thought it was brown.....Besides we ALL KNOW bigger is better.

All right…..I’ll switch to “water is wet”
Old 12-01-2009 | 05:11 PM
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I made this to go with my MSDS headers...setup got me 30HP. Pipes are 3" all the way back.
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Old 12-01-2009 | 05:46 PM
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thats a nice set up, did you get it coated?
Old 12-01-2009 | 06:20 PM
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Originally Posted by Ducman82
thats a nice set up, did you get it coated?
Nope...just a simple high-heat silver paint that we use at work for industrial oven and furnace parts. I did have the headers ceramic coated.

I'm running a fuel cell that is centered in the car so I can get away with routing one pipe out each side.

sorry for oversized and crappy pic......
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Old 12-12-2009 | 01:09 AM
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Tass, running full 3 inch have you noticed any power loss at all?
Old 12-15-2009 | 04:01 PM
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Originally Posted by Tass 928
I made this to go with my MSDS headers...setup got me 30HP. Pipes are 3" all the way back.


Beautiful!




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