definitive headers thread
08-22-2006, 12:26 PM
#1
2nd Gear Member
Thread Starter
Join Date: Apr 2006
Location: Los Angeles
Posts: 247
definitive headers thread
once and for all...the discussion of headers short and long.
we are to discuss the legality of particular brands and set ups and the benefits of short vs. long (including, but not limited to sound and performance). the point has been established, though not conclusive, that shorties gain little hp - so with that given, are we to assume that a signficant amount of money is laid down for little hp and ________? if so, should not the only logical decision be to fork out a bit more cash for the lt?
this hearing is now in session.
we are to discuss the legality of particular brands and set ups and the benefits of short vs. long (including, but not limited to sound and performance). the point has been established, though not conclusive, that shorties gain little hp - so with that given, are we to assume that a signficant amount of money is laid down for little hp and ________? if so, should not the only logical decision be to fork out a bit more cash for the lt?
this hearing is now in session.
08-22-2006, 12:57 PM
#2
3rd Gear Member
Join Date: Mar 2005
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Posts: 864
RE: definitive headers thread
I'll toss in my 2 cents.
The stock exhaust manifolds on the 2005+ Mustang GT's are good enough that there will be no significant difference between them and shorty headers. For what the shortys cost the HP per dollar value is really not good at all. Long tubes will generally give 20 - 30 hp increase provided the computer is tweaked to take full advantage of them. To use LT's you must remove the stock cats. If you're worried about emissions you can use aftermarket cats but they may not be certified. The car may pass an emissions test with a setup like this but it still may not be "legal". Someone correct me if I'm wrong but I'm pretty sure that in the state of California it is illegal to remove any emissions control device regardless of weather or not it was replaced with another device that performs the same function.
Long tube headers will improve power throughout the entire rpm range but the largest gains will be in the midrange and top end. Equal length tubes are best if you can get them as they will ensure that each cylinder has as close as possible to the same breathing capabilities. It is however next to impossible to get equal length tubes on most vehicles. I think there is one manufacturer that claims to make equal length long tube headers for our cars. I don't recal the name though.
Ceramic coating is a must. They keep the heat inside the header pipes much better. It's been my experience that the effect of this is so great that it takes a noticeable load off the cooling system. Any long tube headers will cause the engine to run cooler but the effect is much more pronounced with ceramic coating. Also the ceramic coating doesn't burn an come off like other coatings and it looks good too.
It's been my experience that long tube headers have provided significant gains in power and fuel economy on every car I have installed them on. My only complaint about the headers for the 05+ Mustang GT's is that they are a lot more expensive than they are for most other cars. I am patiently waiting for the price to come down. I do not see why a set of headers for our cars are 2 - 3 times the price of headers for an early 70's big block Chevelle when the amount of work that goes into producing them isn't any different.
The stock exhaust manifolds on the 2005+ Mustang GT's are good enough that there will be no significant difference between them and shorty headers. For what the shortys cost the HP per dollar value is really not good at all. Long tubes will generally give 20 - 30 hp increase provided the computer is tweaked to take full advantage of them. To use LT's you must remove the stock cats. If you're worried about emissions you can use aftermarket cats but they may not be certified. The car may pass an emissions test with a setup like this but it still may not be "legal". Someone correct me if I'm wrong but I'm pretty sure that in the state of California it is illegal to remove any emissions control device regardless of weather or not it was replaced with another device that performs the same function.
Long tube headers will improve power throughout the entire rpm range but the largest gains will be in the midrange and top end. Equal length tubes are best if you can get them as they will ensure that each cylinder has as close as possible to the same breathing capabilities. It is however next to impossible to get equal length tubes on most vehicles. I think there is one manufacturer that claims to make equal length long tube headers for our cars. I don't recal the name though.
Ceramic coating is a must. They keep the heat inside the header pipes much better. It's been my experience that the effect of this is so great that it takes a noticeable load off the cooling system. Any long tube headers will cause the engine to run cooler but the effect is much more pronounced with ceramic coating. Also the ceramic coating doesn't burn an come off like other coatings and it looks good too.
It's been my experience that long tube headers have provided significant gains in power and fuel economy on every car I have installed them on. My only complaint about the headers for the 05+ Mustang GT's is that they are a lot more expensive than they are for most other cars. I am patiently waiting for the price to come down. I do not see why a set of headers for our cars are 2 - 3 times the price of headers for an early 70's big block Chevelle when the amount of work that goes into producing them isn't any different.
08-22-2006, 01:37 PM
#3
4th Gear Member
Join Date: Jan 2006
Location: Nashville Tn
Posts: 1,644
RE: definitive headers thread
I decided against shorties. Too much green for little to no gains. I went with the L/T setup from Dynatech. Pricey, but all inclusive. It has everything you need including x-pipe, cats, harness extensions, bolts and gaskets. Best fitting set I have ever installed. As for the sound - AWESOME. Power gains, yet to get on the dyno again, but I had my tuner tweak the A/F. Seat of the pants says nice gain, especially mid and high range torque. Was it worth the money? Yes, especially considering all that you get in the kit.
08-22-2006, 03:52 PM
#5
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Join Date: Apr 2005
Location: Babylon, NY
Posts: 3,031
RE: definitive headers thread
No one has yet to post before and after dyno numbers of LT's with cats (to be legal). Until then I call B.S. to "20-30hp" with just a header swap with or without a tune just for them.
08-22-2006, 05:31 PM
#6
3rd Gear Member
Join Date: Apr 2006
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RE: definitive headers thread
I'll reply with my .02 cents worth. I just had a set of kooks installed with the x-pipe and free flows. I already had the c/l intake and 93 tune from brenspeed along with the steeda u/d pulliies and the ford stingers. I didn't have a baseline but I would make an assumption I probably was running somewhere between 290 and 296 rwhp. before the install. After the install my dyno #'s were 308.11 rwhp. so my assumption is 12 to 18 rwhp.
08-22-2006, 05:43 PM
#7
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Join Date: Apr 2006
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RE: definitive headers thread
Music city, I had the kook system installed, ***-dyno says good gain, real dyno probably somewhere between 12 and 18 rwhp. Dynoed at 308.11 rwhp. Car sounds like it needs to be racing at a nascar event. Really like the sound of the stingers and headers.
08-22-2006, 05:44 PM
#8
1st Gear Member
Join Date: Aug 2006
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Posts: 119
RE: definitive headers thread
Kooks would be my choice, but $1700 clams is insane...........
Coating vs none. HEAT is the key, heat=scavange, speed. Hense headers DUE scavange better then cast iron logs but headers lose heat. Coatings increase heat, brings HP up.
This info is nothing new and been know for years...........Smokey Unick (sp) did all kinds of crazy tests for more HP.
Hooker has been a leader in years for equal legnth headers, just low quality. IMOP from owning some Super comps on my Impala.
Cost alot, but coating the whole exhaust is good for small HP gain and less heat in the car.
From mr research[:-]
Coating vs none. HEAT is the key, heat=scavange, speed. Hense headers DUE scavange better then cast iron logs but headers lose heat. Coatings increase heat, brings HP up.
This info is nothing new and been know for years...........Smokey Unick (sp) did all kinds of crazy tests for more HP.
Hooker has been a leader in years for equal legnth headers, just low quality. IMOP from owning some Super comps on my Impala.
Cost alot, but coating the whole exhaust is good for small HP gain and less heat in the car.
From mr research[:-]
08-23-2006, 04:55 AM
#9
2nd Gear Member
Join Date: May 2006
Location:
Posts: 313
RE: definitive headers thread
http://www.kennebell.net/techinfo/fo...gtTechTips.pdf
this is straight from the kenne bell site, im sure they have 100s of dyno hours logged in on mustangs. this link also prvides info on timing and ud pulleys and other mods very nice read.
what they say
im not saying i agree/disagree just providing a point of veiw. my .02 cents. long tube ALONE, MAYBE 12-15 on a good day combine with catless x or h pipe and good axlebacks 10 more, so you may make 20 hp with a good PACKAGE. cost $1000 -$2000. depending on manf. and install. Shorties lest say 5-10hp combine with catless x/h pipe ect ect maybe you pick up 17 hp. cost $800- $1200.
so cost per hp lts $50-$100 per hp shories $47-$71 per hp. ive had long tubes on my pervious cars undecided on what im gonna do with this one, im leaning cat back or shorties. i hate raising the hood and seeing these ugly rust looking cast iron manifolds. so if i do headers it will be for looks, sound, and they will help reduce underhood temps a little bit, not much. any hp gains are icing on the cake.
this is straight from the kenne bell site, im sure they have 100s of dyno hours logged in on mustangs. this link also prvides info on timing and ud pulleys and other mods very nice read.
what they say
Exhaust Systems- Sorry but we've seen no gain on a 4.6 GT exhaust system. We've made 600RWHP with stock exhaust. We do know that the Bassani cat back with X pipe makes 10HP. Thats as good as it gets, but who can deny exhaust systems sound great. The Bassani is the best we've tested. Cats? Ive never seen "high flow" cat(s) ever make any more power over a stock cat. A cat will typically burn up to 10HP on a 300HP engine. Dual cats lower it to sHP. Runn 600HP thought duals (300HP per cat) and your back to a 10HP drop.
Headers- Headers make very little if any power. All we've seen is 4-5HP. Same for the accurate magazine test. Cat removal will net around 10HP. In our opinion headres for the 4.6 GT are'nt worth the small peak power gains, expense and the problems that leaks create.
Headers- Headers make very little if any power. All we've seen is 4-5HP. Same for the accurate magazine test. Cat removal will net around 10HP. In our opinion headres for the 4.6 GT are'nt worth the small peak power gains, expense and the problems that leaks create.
so cost per hp lts $50-$100 per hp shories $47-$71 per hp. ive had long tubes on my pervious cars undecided on what im gonna do with this one, im leaning cat back or shorties. i hate raising the hood and seeing these ugly rust looking cast iron manifolds. so if i do headers it will be for looks, sound, and they will help reduce underhood temps a little bit, not much. any hp gains are icing on the cake.
08-23-2006, 05:29 PM
#10
3rd Gear Member
Join Date: Apr 2006
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Posts: 628
RE: definitive headers thread
Yeah I read the Ken Belle thread, sounded like a good add for Bassani cat-back exhaust, a little strange to me that you pick up 10 hp for the Bassani's but nothing for headers. I believe in what I feel and my dyno #'s. Do headers give you 20 to 30 hp probably not, do they give you 10 to 20 hp probably yes. They're a good addition for any future mods you do on your car, like a super charger, they also turn some heads when your cruising. It is a shame that the dealers of these systems can't seem to post some definitive dyno #'s.