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Unread 05-25-2013, 10:38 AM   #1
chris64
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Manifolds vs Headers

Yes , I am sure this topic has been beaten to death, but here goes.
I am not seeing good options for header that fit, aside from the Doug thorley brand.
And this is for a motor that will not see over 3500 rpm.
Fit of headers, and routing of the duals is making me think manifold, y pipe, then a 4 inch mandrel bent single.
Can buy the pipe and bends, and have a nice clean setup.
44 flowmaster methinks as well.
I haven't heard too many comments in favor of headers.
Low rpm and no leaks , and saving $$ with the cast manifolds... wish they weren't so darn heavy!!
C

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Unread 05-25-2013, 05:10 PM   #2
revelc
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Why do you think you need 4"?
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Wag Rebuilt 360, 260H, 727, Locked 44, AMC 20, 208, 31" M/T's, 4" Rustys, 2.5" Duals. SOON:SOA SF, 496, T400, Doubler, D60's, 37" M/T's <-TOY
Cherokee Rebuilt 360, 2" Duals, mostly stock. SOON: Hot Street 401, 4'' Rustys, 33" BFG A/T's maybe a T-case to get rid of Q-Track <-TOW RIG
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Unread 05-25-2013, 06:19 PM   #3
RockRollin
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Quote:
Originally Posted by revelc View Post
Why do you think you need 4"?
I agree. 2-1/2" is plenty for a slightly modified 360. The stock manifolds do breath pretty well also. The bottle neck is in the y-pipe, have one built if you want better flow. Most of them off the shelf only have a 1-1/2" hole where the drivers side connects.
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Unread 05-25-2013, 09:01 PM   #4
revelc
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I run 2" duals on the Cherokee off the manifold with what look like some 44's. Breaths really well and sounds good.

I have 2.5" duals off the manifolds and through thrush welded mufflers on the Wagoneer. But it's running a warmed over 401.

I am considering getting the Dougs with 2.5" duals on the Cherokee for its 401 I'm building. It will be over 400HP 500ish Ft/lbs and that should be plenty of pipe for it.

If your running a modded 360 the biggest you'll need is 3".
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Wag Rebuilt 360, 260H, 727, Locked 44, AMC 20, 208, 31" M/T's, 4" Rustys, 2.5" Duals. SOON:SOA SF, 496, T400, Doubler, D60's, 37" M/T's <-TOY
Cherokee Rebuilt 360, 2" Duals, mostly stock. SOON: Hot Street 401, 4'' Rustys, 33" BFG A/T's maybe a T-case to get rid of Q-Track <-TOW RIG
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Unread 05-27-2013, 08:29 AM   #5
chris64
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Was thinking 4" just because there is so much room , and with the lift, getting over the axle would be easy.
Ok, 3" then, but getting around transfer case is a little tricky looking.
I may use the down pipes on it, with a new ypipe collector from summit.
Would someone be kind, and post some pics of their exhaust setups, please ?
Thank you, C
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Unread 05-27-2013, 08:37 AM   #6
Crawlerkid
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You don't want to go too big, or you'll lose the velocity in the pipe, and actually be a performance hindrance.
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Unread 05-27-2013, 08:50 AM   #7
revelc
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Quote:
Originally Posted by Crawlerkid
You don't want to go too big, or you'll lose the velocity in the pipe, and actually be a performance hindrance.
X2

You'll lose low end. Does the engine have any mods? If not even 3" might not be necessary.


This isn't the set up your going with but is another idea.

image-1766800100.jpg



image-3030996402.jpg



image-3831953645.jpg

Other side

image-1598659164.jpg

Mine run through my lift springs so they won't get crushed.

image-637090194.jpg



image-1617959733.jpg


I wanted duals but wasn't interested on advertising it being modded. Everything is tucked up nice and neat.
image-3332126112.jpg


Some other guys run their pipes on both sides of the t-case and tie them in together after it.
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Wag Rebuilt 360, 260H, 727, Locked 44, AMC 20, 208, 31" M/T's, 4" Rustys, 2.5" Duals. SOON:SOA SF, 496, T400, Doubler, D60's, 37" M/T's <-TOY
Cherokee Rebuilt 360, 2" Duals, mostly stock. SOON: Hot Street 401, 4'' Rustys, 33" BFG A/T's maybe a T-case to get rid of Q-Track <-TOW RIG
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Unread 05-27-2013, 09:16 AM   #8
chris64
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Thanks for the pics!
Engine will have .030 pistons, valve job, Performer intake, holley 650, cast manifolds, HEI , and a moderate cam
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Unread 05-27-2013, 09:55 AM   #9
revelc
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Quote:
Originally Posted by chris64
Thanks for the pics!
Engine will have .030 pistons, valve job, Performer intake, holley 650, cast manifolds, HEI , and a moderate cam
You'll probably benefit from 3" then.

If you have upped the compression and its performance oriented maybe you should save like I am for the Doug's and go from there.

If you choose headers down the road it might cost you again to rework everything to work with them.
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Wag Rebuilt 360, 260H, 727, Locked 44, AMC 20, 208, 31" M/T's, 4" Rustys, 2.5" Duals. SOON:SOA SF, 496, T400, Doubler, D60's, 37" M/T's <-TOY
Cherokee Rebuilt 360, 2" Duals, mostly stock. SOON: Hot Street 401, 4'' Rustys, 33" BFG A/T's maybe a T-case to get rid of Q-Track <-TOW RIG
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