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Author Topic: Exhaust for a 383 Stroker, 405 HP and 450 TQ  (Read 1621 times)
plckidd
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« on: September 02, 2011, 03:42:16 PM »

I am in the process of buying a stroker engine and I'm a little unsure of what type of exhaust to run. I thought about 1 3/4 shorty headers, free flow converter and two Borla mufflers. Using 2 1/2" from headers to mufflers and 3" to tips. Does anyone have any recommendations? Is back pressure going to be a factor if using a converter? Thanks, Shawn
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ryeguy2006a
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« Reply #1 on: September 02, 2011, 07:04:15 PM »

Typically you should run the opposite of what you are proposing. You would want a larger diameter pipe running into a smaller diameter pipe. Reason being that the exhaust temperature will cool as it travels through the exhaust causing the air to shrink, and when the pipes become smaller it would create more back pressure. At least that is what I am told. I have a 3" exhaust from the collectors back. Hope that helped a little.
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badmonkey
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« Reply #2 on: September 02, 2011, 08:09:06 PM »

With only 405 HP, use 1.625" long-tubes, dual 2.5" is more than enough, and forget any 3" parts.
 You could make it easy on yourself and just use Hooker's 2.25" dual exhaust with their matching headers. Still plenty of flow for no restriction past 440 HP, if you choose mufflers wisely.
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LeighP
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« Reply #3 on: September 03, 2011, 12:38:39 AM »

I agree...no need for more than 2.5" diameter tube.
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silver78
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« Reply #4 on: September 03, 2011, 12:43:02 PM »

2.5" pipe dia is sufficient, skip the cat converters unless you have to for emissions reasons or you desire more sound canceling, use long tube headers instead of shorties. just my .02 
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plckidd
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« Reply #5 on: September 03, 2011, 02:55:13 PM »

With only 405 HP, use 1.625" long-tubes, dual 2.5" is more than enough, and forget any 3" parts.
 You could make it easy on yourself and just use Hooker's 2.25" dual exhaust with their matching headers. Still plenty of flow for no restriction past 440 HP, if you choose mufflers wisely.

Thanks for the advice. Would the 1.625 headers give me more power on the top end?
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badmonkey
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« Reply #6 on: September 03, 2011, 08:16:12 PM »

With only 405 HP, use 1.625" long-tubes, dual 2.5" is more than enough, and forget any 3" parts.
 You could make it easy on yourself and just use Hooker's 2.25" dual exhaust with their matching headers. Still plenty of flow for no restriction past 440 HP, if you choose mufflers wisely.

Thanks for the advice. Would the 1.625 headers give me more power on the top end?
No, but they're not the limiting factor. And they will give you more average power than 1.75" shorties.
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