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Old 09-08-2014, 11:48 AM   #1
Mayfield
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Another exhaust size question

Just wanted see what everyone's thought was.
5.3 with cam & LT with 3" collector.
So I originally was going to run 2.5" piping, but all the local exhaust shops around here only have the crush bend style benders not mandrel. Closest one I can find is about 5 hours away, that's just not feasible.

So now I'm thinking of going with 3" since it's not going to be a true 3" all the way through. I don't have easy access to a welder to fab my own. I'm also going with a H-pipe.

So what would you do, original plan of 2.5" or go 3" because of the crush bends?
I know I'm probably over thinking this, but I don't want it to be too restrictive, or go to big cause I need some back pressure.
Some guidance would be great lol. Thanks
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Old 09-08-2014, 02:55 PM   #2
littlevictories
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Re: Another exhaust size question

unless they really suck at using the bender you're talking like 5hp with mandrel. imo not worth the upgrade to 3" pipe dollar wise. also 3" pipe is a bit loud for my tastes.

if your really picky, buy a mandrel kit offa summit and take it to them to weld it up.
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Old 09-08-2014, 03:29 PM   #3
Low Elco
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Re: Another exhaust size question

I bought 2.5" u-bends and bungs and flanges from Summit and some pipe locally and made my own. Easy peasy.
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Old 09-08-2014, 04:13 PM   #4
Xeen
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Re: Another exhaust size question

I wouldn't sweat it, 2.5" dual exhaust with an H-pipe is fine even with a crush bend.
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Old 09-08-2014, 06:21 PM   #5
BR3W CITY
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Re: Another exhaust size question

Quote:
Originally Posted by Low Elco View Post
I bought 2.5" u-bends and bungs and flanges from Summit and some pipe locally and made my own. Easy peasy.
I'd say the same thing. Summit or Jegs or whoever will have the bend kits for $60-150, and you can buy more than one or individual pieces. You can camp it together and then have the local exhaust shop weld it up for you.
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Old 09-09-2014, 01:04 AM   #6
crazy longhorn
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Re: Another exhaust size question

Agree , with the rest of the crowd....2 1/2" is plenty, ad the H pipe, good to go! I worked in exhaust , 4 or 5 yrs....don't know it all, but was taught by a man with 45yr in the bizz....man that is a bunch of yrs burning oneself! What I understand, from what he showed me, is that as the exhaust cools down, toward the rear....the bends , nor the pipe sizing will hurt the flow. Up front, where the exhaust is "hot", sharp bends will indeed hurt you on the performance? Many guys will opt for a set of long tube headers, & run as straight as you can to the muffs...after the muffs, the point is moot on the crush bent pipes (to a point)? I will say a sharp bend on a 3" pipe , will crush more than it will an the smaller (2 1/4 or 2 1/2" pipe)/ Longhorn
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Last edited by crazy longhorn; 09-09-2014 at 01:06 AM. Reason: Typo
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Old 09-09-2014, 12:38 PM   #7
Mayfield
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Re: Another exhaust size question

Thanks for all the replies. I figured I was over thinking it. 2.5" it is. I'm going to order my mufflers today. Hopefully I'll have the exhaust
Ran in a few weeks.
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