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Discussion Starter · #1 ·
hey ive noticed here in our forum that ive seen a lot of people rebuilding thier engines, spending tons on new parts. then slapping on there old manifolds. any reason why? are headers over rated or something? lol what am i missing here?
 

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No, they're not over-rated but some people want to keep their car as stock as possible, or they're worried about leaks. I've not had that problem with mine but some do.

If you're doing a mild performance build I'd suggest the short tube headers that connect about where the stock manifolds attach to the pipes but if building a high performance motor I'd go with full length (and equal length) headers.

It's about RPM tuning. Shorter length manifolds/headers make good torque down low where longer tubes work better in the upper RPM ranges where hypo motors run.

Hope this helps.

John
 

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I've not read posts where people doing performance upgrades have returned to stock manifolds over headers. About the only reason to use stock manifolds is when you can't find headers that you can make work. The other obvious reasons people may have for using manifolds are money and retaining stock appearance. Anyone who understands engines knows that you can't get get more air into the engine than you can get out of it, so if the exhaust side is the choke point then intake and cam changes will not be as effective as they would otherwise be. For stock type and mild engine rebuilds stock manifolds may be just fine for low RPM and high torque applications. I'd think headers are not over rated and critical if you need to enhance the exhaust flow from your engine, over what the manifolds can provide.
 

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Also headers and exhaust work can become very expensive, especially if there aren't any ready made kits for your car. The simple solution is to use the manifolds and stock exhaust while you save up to get those headers and the rest of your exhaust work done.
 

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It's amazing to me how many people seem to have trouble installing headers..Yes I know they can be tricky in certain combinations but even the simplest setups seem to cause problems for some people...You also hear of these same people chasing leak after leak and swearing off using anything but cast iron manifolds...Over the years I have probably had as many leaky exhaust manifolds as I have with headers...I would never even consider running manifolds on a performance engine..
 

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The first time I installed mine it took hours and that was when installing the old new engine. We 4 guys working on it and had that thing hanging every which way and used a huge mallet on the headers to get them into place. :tdn:

When installing the engine I heard a tip from someone about loosely bolting the headers onto the engine and then lower it into place. Took two of us about ten minutes to drop in the engine and headers! :tup:

Sometimes it's all on how you hold your tounge!

John
 

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When I first dropped my engine I tried doing it with the headers on and that didn't work out so well. Got the engine in without the headers and then tried putting them in from the top, again didn't work. Went from underneath but STILL no clearance (steering components and motor mounts in the way). I finally got fed up, unbolted the motor mounts from the frame, reattached the hoist, and lifted the motor up a couple inches and FINALLY got the headers in!!!

...And then I had to put the transmission in >:-(

I did finally get everything in and now I'm chasing an exhaust leak, but I'm pretty sure the leak is somewhere near #7 or #8.
 

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On my 289, I have tri-y headers from Scott Drake. I bought them raw and had them coated with ceramic grey. Now the question about increase in HP and torque. Will the long tube out perform the tri-y in all areas . Should I have put in the long tubes. Pulled great on the dyno with 209hp at the rear with 256 ft lbs of torque at 5500 rpm. Will this change help the top end. I will not put the little log manifolds back on this 289. Gotta love the exhaust note.

Thanks

Greg
 

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I run Dougs tri-y's on my Falcon. Pass side went in from underneath no problem. Drivers side was another story. Had to remove motor mounts (all three parts) and lift engine a bit. Then there's the z-bar, which runs through the header! Finally installed them together as a unit and it went in. Snugged down the header bolts, went for a hotlap, and re tightened. That was a couple years ago and never had a leak. I must say these Dougs Headers fit beautifully. No clearance issues at all(once they're in). Works of art but pricey.

Matt
 

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My experience has been most long tube headers can't be installed along with the engine..The tubes are just too wide apart from collector to collector in most cases...In extremely tight situations like big block mustangs I have laid the headers in place first into the engine bay and then sat the engine almost in..Leave it hanging just a few inches up to give yourself lots of room to tighten up the header bolts and then finish dropping the motor the rest of the way in....On my 408 I install the engine with one header completely attached to the engine and then snake the drivers side up into place after the engine is installed onto the mounts...Rarely can long tube headers be dropped in from above but the Tri-ys seem to be an exception...They are about the easiest headers I have ever installed other than the fact they hit the clutch linkage and bellhousing. :D
 

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Geeez Funny mine hit the bellhousing as well . Ya think they could have made them fit. These were not the most expensive headers around. $150 for uncoated headers.




Greg
 

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Discussion Starter · #13 ·
No, they're not over-rated but some people want to keep their car as stock as possible, or they're worried about leaks. I've not had that problem with mine but some do.

If you're doing a mild performance build I'd suggest the short tube headers that connect about where the stock manifolds attach to the pipes but if building a high performance motor I'd go with full length (and equal length) headers.

It's about RPM tuning. Shorter length manifolds/headers make good torque down low where longer tubes work better in the upper RPM ranges where hypo motors run.

Hope this helps.

John
awh, cool. short headers for low end torque, and long for high end torque. mine 289 will be a mild build. short it is. ill prob just make headers my last upgrade then. thanks
 

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My understanding has always been that long tube headers build more torque than shorties, and that should apply lower in the RPM range.
 

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My understanding has always been that long tube headers build more torque than shorties, and that should apply lower in the RPM range.
No, long tubes are better in the upper RPM ranges. The Tri-Y's that people are talking about here are probably better than shorties and both are better than manifolds but are still a limiting factor in making big power. They too are designed for low to mid RPM usage. If you're building for torque (pulling power) shorties or tri-Y's would be the better choice in my opinion.

John
 

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From what I have seen long tubes are usually better everywhere but rule of thumb is long tubes for bottom end torque and shorties for high rpm power..The Tri-ys are supposed to be better than 4 into 1 style headers for bottom end but it really all depends on the design of the exact header in question..
 

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From what I have seen long tubes are usually better everywhere but rule of thumb is long tubes for bottom end torque and shorties for high rpm power..The Tri-ys are supposed to be better than 4 into 1 style headers for bottom end but it really all depends on the design of the exact header in question..
I always thought long tubes would be better for performance. But, have seen comparisons where the tri-ys did better. I am going with Tri-ys because of fitment, haven't found long tubes that fit my comet without modifying and not going to beat on a new pair of $600 pipes.

here is one of the comparisons where tri-ys did better from car craft
http://www.carcraft.com/techarticles/dual_quad_ford_302_engine/index.htmlhttp://www.carcraft.com/techarticles/dual_quad_ford_302_engine/photo_07.html

Lou
 

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I always thought long tubes would be better for performance. But, have seen comparisons where the tri-ys did better. I am going with Tri-ys because of fitment, haven't found long tubes that fit my comet without modifying and not going to beat on a new pair of $600 pipes.

here is one of the comparisons where tri-ys did better from car craft
Crate Eight! Dual-Quad Ford 302- Car Craft Magazine

Lou
I think I would consider Tri-Y's as long tube headers.
 

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From what I have seen long tubes are usually better everywhere but rule of thumb is long tubes for bottom end torque and shorties for high rpm power..The Tri-ys are supposed to be better than 4 into 1 style headers for bottom end but it really all depends on the design of the exact header in question..
Maybe its a phenomenon only in Canada, eh?
 

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