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Old 09-19-2010, 01:07 PM   #1
jasonroman
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headers....should be run with true duals only?

well a while back, i went through exhaust nightmare. but at the time i didnt have headers so, i just had guy put on a new cat back exhaust.
i just picked up a set of headers. and looked for a couple prices on getting them put on.
one guy told me 300 to make headers work with my current exhaust.
which is manifolds, a y pipe i guess. that go into, new cat, new pipe to muffler, and at muffler i have two pipes running out and exiting behind rear wheels
another shop told me theres no point tying into the current piping. headers should be run tru dual, for power and performance.
no price yet, needs to look at it....
3rd shop, guy told me today around 800 plus whatever is involved getting the manifolds off....

800, dont have it, but if i did, i think id spend it on lowering my truck rather than doing the exhaust a 2nd time.
first time ran me 500 and alot of headache.

looking for info or advice.

unfortunateley i am not much of a mechanic at all, so i dont think ill try cutting off new piping and re piping myself.
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Old 09-19-2010, 02:44 PM   #2
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Re: headers....should be run with true duals only?

You can run headers without True Duals. Unless you have a lot of mods it's better to use the y-pipe because you need backpressure. Your best bet would be to have your current exhaust tie into the headers, it's a matter of cutting and welding.
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Old 09-19-2010, 02:48 PM   #3
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Re: headers....should be run with true duals only?

well as for mods, i have none at the time.
stock 350. id like to change carb, intake mani and maybe have cam changed.
but right now its all stock.
my old 82 c10 had headers, carb, intake mani, not sure about cams, had 305 heads, and if i got on the gas, id lay a patch 100yrds, this truck, i stand on gas, and theres a lag, and then go, no wheels spin. unless wet...
not 17 looking to leave patches every where.
but i had a similar truck with similar parts, that sounded and ran much stronger.
thats what im looking for in this truck
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Old 09-19-2010, 02:55 PM   #4
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Re: headers....should be run with true duals only?

Yeah... at this point if you go TD's you'd lose more power. At least on the low end.
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Old 09-19-2010, 02:57 PM   #5
jasonroman
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Re: headers....should be run with true duals only?

so you suggest i keep my current system and have the headers tied into whats existing?
last thing i want to do is loose power im trying to find.

Last edited by jasonroman; 09-19-2010 at 02:58 PM.
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Old 09-19-2010, 04:09 PM   #6
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Re: headers....should be run with true duals only?

you will be fine tying your existing exhaust into your headers. Ive got a warmed up 400 ,3in. to the muffler & 2 -2.5 pies exiting the back . Many reputable gearheads told me this was plenty of flow for what Ihad . True duals may not hurt you that bad ,but certainly wont help you.
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Old 09-19-2010, 04:26 PM   #7
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Re: headers....should be run with true duals only?

i guess if it wont hurt thats a good thing. i plan on changing a couple things later on. but i know this much, i dont want to pay to have my exhaust done 3 or 4 times.
thats why im looking for opinions on which way to go.
simple things not big motor mods are in store. dont know enuff and dont have the extra money to go big with the motor.
like i said before, eventually ill get a carb, intake mani, cam.
and then go from there i guess
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Old 09-19-2010, 04:38 PM   #8
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Re: headers....should be run with true duals only?

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Originally Posted by BlueMagicSS View Post
...because you need backpressure.
When will this myth die?
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Old 09-19-2010, 04:40 PM   #9
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Re: headers....should be run with true duals only?

not a myth try running anything open headers it will have a big loss in power.
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Old 09-19-2010, 04:46 PM   #10
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Re: headers....should be run with true duals only?

and there is my problem....
as a guy who dont know much about motors, hp. or how to make it.
i come to the forums for a little insight.
i get mixed reviews when it comes to my problem.
heard not run the headers with my current set up. total loss. no point and no power gain.
then i heard run what i have, add headers.
??
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Old 09-19-2010, 05:17 PM   #11
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Re: headers....should be run with true duals only?

welcome to the internet. If you want the headers on there,then I would go ahead and tie them into your existing system and try it out.Maybe later on down the road you can switch to dual exhaust and try that.You'll then be able to compare the two and know what works best.
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Old 09-19-2010, 05:39 PM   #12
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Re: headers....should be run with true duals only?

yea i guess thats my option
spend 2grand on exhaust 3-4 times....
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Old 09-19-2010, 05:51 PM   #13
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Re: headers....should be run with true duals only?

http://books.google.com/books?id=6JI...page&q&f=false
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Old 09-19-2010, 05:55 PM   #14
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Re: headers....should be run with true duals only?

Headers can be a head-ache. I can't dispute they improve exhaust flow, which I guess can be a good thing. But if you have an emission system that ties into your exhaust manifolds (A.I.R. system) you have to figure out how to get rid of it or make it work with headers. You have to be careful about your plug wires, because headers are famous for ruining them. You have your O2 sensor to worry about. Then you have to worry about whether or not the improved flow of exhaust due to the headers has thrown your exhaust gas temperature off enough to cause the computer to throw a code. And you have to worry about how close the headers are to your starter motor. Headers kill starter motors. Then you wind up with a class A pain in the tookis trying to get the piping from the collectors to the cat without hitting crossmembers, your floorboard, or hanging down so low it looks like crap. And after all that, unless you bought a high-dollar set of headers made of stainless or ceramic coated, the paint burns off and they look like dog doo in 6 months. On a stock or mild built engine I really think they aren't worth the trouble. Especially on computer controlled engines.
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Old 09-19-2010, 08:06 PM   #15
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Re: headers....should be run with true duals only?

If I ever get an exhaust built for something by a shop on a small clock i would run ramhorn manifolds.. But I like my headers except for leaks that sound bad.
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Old 09-19-2010, 08:07 PM   #16
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Re: headers....should be run with true duals only?

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Originally Posted by 3r!c84 View Post
not a myth try running anything open headers it will have a big loss in power.
You don't lose power with open headers because you don't have back pressure; you lose power with open headers because you have no exhaust gas velocity or scavenging effect.

Last edited by foamypirate; 09-19-2010 at 08:07 PM.
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Old 09-19-2010, 11:32 PM   #17
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Re: headers....should be run with true duals only?

backpressure is a myth. It has nothing to do with the exhaust. bigger pipes will make more power period. header tube size however is very important. due to scavenging.
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Old 09-20-2010, 12:24 AM   #18
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Re: headers....should be run with true duals only?

the link i put in my post tells you some good info
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Old 09-20-2010, 12:58 AM   #19
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Re: headers....should be run with true duals only?

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Originally Posted by 3r!c84 View Post
not a myth try running anything open headers it will have a big loss in power.
I could not agree more. I recently swapped in a 455 in my '72 Cutlass and have been running open headers for the 50 or so miles ive driven it and you can definitly tell that the open headers are hurting the power, but should have full exhaust by the weekend
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Old 09-20-2010, 03:15 AM   #20
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Re: headers....should be run with true duals only?

http://www.veryuseful.com/mustang/te...Scavenging.pdf
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Old 09-20-2010, 03:15 AM   #21
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Re: headers....should be run with true duals only?

Throw the headers on a shelf and pull them out once you've done an intake and cam to take advantage of them. I assume there are emissions issues in NJ. Once you put them on I'd look at a y-pipe into a single aftermarket CAT and tie into your existing from there. If you want seat of the pants improvement, regear your rear end with some shorter (numerically higher) gears. Also save up for a heat shield for your starter and some plug wire boots. The little things make a difference.
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Old 09-20-2010, 08:10 AM   #22
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Re: headers....should be run with true duals only?

Some of you open header myth guys are listening to too many uninformed wannabe old farts spouting "back in the day" knowledge that was never tested.
Dyno and track testing will generally show slight power gains from open headers, I've never seen one lose power.
You're trying to get exhaust gases out the cylinder, why would reverse/backpressure help?
If you've got the big factory exhaust system, two into one would probably be fine on a mild 350.
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Old 09-20-2010, 11:27 AM   #23
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Re: headers....should be run with true duals only?

I think most people mean scavenging, they just call it back pressure...
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Old 09-20-2010, 12:50 PM   #24
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Re: headers....should be run with true duals only?

^ kinda tough to mix those two up, they're actually the opposite thing...
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Old 09-20-2010, 03:30 PM   #25
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Re: headers....should be run with true duals only?

Quote:
Originally Posted by BigBlocksRule View Post
Some of you open header myth guys are listening to too many uninformed wannabe old farts spouting "back in the day" knowledge that was never tested.
Dyno and track testing will generally show slight power gains from open headers, I've never seen one lose power.
You're trying to get exhaust gases out the cylinder, why would reverse/backpressure help?
If you've got the big factory exhaust system, two into one would probably be fine on a mild 350.
new i was a old fart did not know i was a wannabe i do agree tho

Last edited by nbpro; 09-20-2010 at 03:32 PM.
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