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Discussion Starter #1
I'll be adding a new exhaust system to my 351C-2/V soon and was wondering what everyone thinks about Headers. I've been told that keeping the original exhaust manifolds would be ok and to just run the dual exhaust with some nice flows. Of course I love the sound of headers but will any added horsepower offset the negatives? In the future (as soon as Dave gets done with his! lol) I'll be doing a 4V conversion but other than maybe a little dress up I don't think I'll be doing any other engine mods. I'm still a little undecided about the headers though. Thanks!
Tony
 

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Tony, if you dont plan on anything else, headers are not worth the cost and hassle if you ask me. There a pain in the A** to work around and tend to be prone to leaks etc. A good dual setup on the original mainifolds work quite well on a fairly stock motor. Of course its up too you to decide. mm
 

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Stock exhaust manifolds are really restrictive compared to headers. Headers will make your exhaust a bit louder, but not a whole lot. How loud you want your exhaust to be, really depends on the type of muffler you choose. You should gain some from the headers, but most of the gain and performance you will see from the headers is when you do the 2v-4v conversion you spoke of. Hedman makes a great pair of ceramic coated headers for the money.
 

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Headers or not...

Both my 73 BetaCat and the wife's 70 Mach have 351C-4Vs and neither has headers. Wife's Mach is a 21,000 mile all-original, untouched, unrestored and will never see headers! It runs just fine with the 4V exhaust manifolds and full duals! BetaCat also has the stock 4V manifolds and full duals, but 'turbo' mufflers instead of the stock mufflers. Wife's Mach will turn a 15.0 with the stock exhaust, and would go quicker if she'd let me install a posi rear end! BetaCat will run 14.40s with just a rear gear change from 3.25s to 3.70s, but you also have to remember that CJ cars got a factory 10.25" high-stall converter! BetaCat is getting a little winded above 5200rpm, but that is due to the camshaft more than anything else.

You have to remember that if you're changing from 2V to 4V heads, you'll aso need to upgrade both your intake manifold and your exhaust manifolds to 4V port sizes! Remember that the 4V heads have bigger intake and exhaust ports than the 2V heads! The biggest problem you'll face is finding a set of 4V exhaust manifolds. And to think of the sets that I had thrown away back when...

Another thing to remember. If you decide to go with headers (if you do) also make sure to specify 4V ports! You can generally use 4V headers on 2V heads, but not the other way around. The ports on the 4V heads are so much bigger than the 2Vs that the sealing bead on the header flange of 2V headers won't cover the 4V port!
 

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Discussion Starter #6
Thanks guys. I hope I didn't confuse anyone. I won't be changing the heads, only adding a new intake so I can switch to a 4 barrel carb. I priced out the Peformer Intake and a 600 carb so that's really the only change I'll make to the engine. (except maybe the pertronix ignition) My car's also an original, untouched 51,000 car so I only want to make some minor changes to add a few horse. I think I'll wing this one and make a last minute decision when it comes time to do the exhaust. Of course if anyone has any other imput I'm all ears.
T
 

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headers...my 2 cents

I just put a set of hooker headers on my '69 ss. It's a 351 windsor. Yes, it was a pain to put them on, but the immediate horsepower gain made all the work and struggle worth while! My cougar is all original-70,000 mile car. I just put the stock exhaust manifolds in the garage, that way if I want to put it back to stock, I'm set. I like the extra power, I like the extra rumble. I'd do it again. Pat
 

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I'm currently running headers on my 351C. If it is just a weekend cruiser I wouldn't hesitate to go with headers, but highly suggest you go with some kind of ceramic coating or other coating process. Uncoated headers create lots of heat in the engine bay and tend to burn up plug wires, etc. If you have the cash for coated headers, go for it. Otherwise, don't bother with headers at all as uncoated headers are not worth the headache. A previous cougar I had ran uncoated headers, what a PITA.
 

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here is pictures from desktop dyno

a picture is worth a thousand words first picture is stock engine 351 second is adding headers and third is adding big tube headers as you can see not much is gained by the big tube headers for your car but there is a marked improvement from stock exhaust to headers.
 

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here is two with headers
 

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and now for three
 

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Discussion Starter #12
Header's it is but from the sound of things it looks like I should hold out till I can get the coated ones. Would it make any sense at all to run the new dual exhaust with the original exhaust manifolds untill I can spring for the headers? Or should I just wait and have it done all at once. I have a good friend at a muffler shop who will be doing the work. (not free but cheaper than others) Any idea on price and where to buy the coated headers? Thanks a bunch guys, I appreciate all the help I can get.
 

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check this header site out

Its a ford power train application site might help you decide on your headers. www.fordpowertrain.com worth a look Dan
 

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I just paid $365 for a set of Hooker ceramic coated headers for a cleveland.
 

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Tony, I hate to bring this back up but..... I just spent all day under a 73 Mustang with a 351 C and headers. I now have my mind made up for sure unless your looking for MAX horsepower and not just a driver, DO NOT bother with these pain in the a** things called headers.

We had to change out trannies in the car today and these headers and not worth it, you cant hardly even get the upper starter bolt out!! There in the way of everything. Thats it do what you want I just had to look this old post up and let off some steam!:angryfi: mm
 

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My 70 xr7 came with headers when I bought it, so I am stuck with them for now, it's a 351C 4v, my parts cars has the original exhaust manifolds but it is a 2v. I need to replace the header gaskets, NOt looking foreward to it.
 

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Actually, the header gaskets aren't bad to replace. I had to do mine a couple of times. Just get the one piece gaskets that have the U shaped bolt holes on the ends. Remove all but the end bolts and drop in the new one.
The real pain was putting the headers in originally. What a PITA. And I had a lift at the time!
 

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I had my Hookers put on my 351W when I had the dual exhaust installed, so I can't speak about the pain of installation. The only thing I hate is the heat they radiate. The engine does run stronger, with only headers/dual exhaust added as of now. The old exhaust manifolds hold down my wifes' flower pot, just kidding.
 

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Discussion Starter #20
MM..it's always good to vent. I already decided against the headers for now but appreciate your advice. I'll be having the dual exhaust run with some flowmasters or similar mufflers next week. If I feel the need for more speed I'll add the headers this winter. (although here in Florida there really isn't a winter is there?:)
 
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