Shorty Headers
- Thread starter Fubar
- Start date
cobrar1339
GT Owner
A very promising project, I think those of us in the US of Calif will be keeping a close watch on this project. Pipes for the track and cats for the street, what's not to like.
Shorty's don't normally make as much power, but those are not like your typical 4.6 shortys for a Mustang at all. You have way more room to work with and these really look much different. Similar to a C5 Vette Shorty but still a couple notches better.:thumbsup It will make a sound difference over stock even if you ran through the cats IMO. It should give it the rasp of the long tubes I like.
I guess 22-26 RWHP with that set-up.
I will be in Dallas week after next, would love to hear it if it's all together.
Shorty's don't normally make as much power, but those are not like your typical 4.6 shortys for a Mustang at all. You have way more room to work with and these really look much different. Similar to a C5 Vette Shorty but still a couple notches better.:thumbsup It will make a sound difference over stock even if you ran through the cats IMO. It should give it the rasp of the long tubes I like.
I guess 22-26 RWHP with that set-up.
I will be in Dallas week after next, would love to hear it if it's all together.
It is all together and running great! I am waiting to get it on the same Dyno I ran just before the change. I will let you guys know when that is done.
soroush
Ford Gt Owner
- Aug 8, 2007
- 5,256
Outstanding!
Mark,
Does your builder have a jig to make duplicate sets of the headers without having a GT on hand to fit them? I would love to buy a set. GREAT WORK!!! :thumbsup :cheers :banana :cheers :thumbsup
Chip
Mark,
Does your builder have a jig to make duplicate sets of the headers without having a GT on hand to fit them? I would love to buy a set. GREAT WORK!!! :thumbsup :cheers :banana :cheers :thumbsup
Chip
Juan Cooldude
GT Owner
- Jul 1, 2008
- 102
I didn't do a before/after recording (wish I had) but it is pretty loud. I still have the Borla canister on there so it is just a bit throatier than an X-Pipe.
He did save the jig so he can crank out some more.
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I'm in.
Gentlemen,
I am going to buy a set of these. Though they are somewhat pricey, about double the cost of the Ford Racing headers, the quality of materials and construction combined with their interchangeability with the stock exhaust manifold requiring no modification to my existing exhaust system makes them most desirable to me. It's a long shot but I wonder if there are nine other members who were interested so that we can take advantage of the group pricing of $4500. I'm going to have a set made regardless. Any other takers?
Chip
Gentlemen,
I am going to buy a set of these. Though they are somewhat pricey, about double the cost of the Ford Racing headers, the quality of materials and construction combined with their interchangeability with the stock exhaust manifold requiring no modification to my existing exhaust system makes them most desirable to me. It's a long shot but I wonder if there are nine other members who were interested so that we can take advantage of the group pricing of $4500. I'm going to have a set made regardless. Any other takers?
Chip
Indy GT
Yea, I got one...too
OE Manifolds
Mark, I kinda agree with jdoc7 here. I am interested to see if your before and after dyno runs point to any appreciable power increase. I doubt you will see any if all. And if a delta does surface it may be due to different ambient day test conditions.
But I think I understand your motive is more apprearance than performance and if that is the case, go for it! (and Chip too!). The cast iron units are pretty free flowing and as you state there is not much transmission length from the exhaust port to the cat entrance. Talking to the Roush engine guys I do not believe there is much if any flow restriction on the exhaust side caused by the OE cast iron headers. So I would anticipate little if any recognizable performance to be gained (maintaining the cats and OE muffler system).
Mark you asked why they used cast iron manifolds. I guess I would ask what would you think might be better? Cast iron is industry standard and yes the GT is a special car, but I think the only considered option would be tublar headers, which probably cost significantly more than the cast units, offer little if any performance delta and may have durability issues (i.e. thermal fatigue) which Ford certifies the car to. I just think there was little if any option on the cast iron OE units. Just my opinion and also welcome a build team member for internal comments on this topic.
But I am excited for your addition and am looking forward to seeing it in person in Vegas!
Mark, I kinda agree with jdoc7 here. I am interested to see if your before and after dyno runs point to any appreciable power increase. I doubt you will see any if all. And if a delta does surface it may be due to different ambient day test conditions.
But I think I understand your motive is more apprearance than performance and if that is the case, go for it! (and Chip too!). The cast iron units are pretty free flowing and as you state there is not much transmission length from the exhaust port to the cat entrance. Talking to the Roush engine guys I do not believe there is much if any flow restriction on the exhaust side caused by the OE cast iron headers. So I would anticipate little if any recognizable performance to be gained (maintaining the cats and OE muffler system).
Mark you asked why they used cast iron manifolds. I guess I would ask what would you think might be better? Cast iron is industry standard and yes the GT is a special car, but I think the only considered option would be tublar headers, which probably cost significantly more than the cast units, offer little if any performance delta and may have durability issues (i.e. thermal fatigue) which Ford certifies the car to. I just think there was little if any option on the cast iron OE units. Just my opinion and also welcome a build team member for internal comments on this topic.
But I am excited for your addition and am looking forward to seeing it in person in Vegas!
Juan Cooldude
GT Owner
- Jul 1, 2008
- 102
B O N Y
MODERATOR & FGT OWNER
We asked the gentleman to be a sponsor, this group buy is $45k. He has not replied yet, so I assume the answer is no.
Please read Indy's reply above, also contact Shadowman and get the real dope on what improvements in performance you can expect.
Bony
Moderator
Please read Indy's reply above, also contact Shadowman and get the real dope on what improvements in performance you can expect.
Bony
Moderator
Aluminum?
Gentlemen,
This is a topic about which I have zero knowledge or experience. I assumed, since the GT uses aluminum heads and block, that the exhaust manifolds would be cast aluminum as well. Aluminum would be lighter than the cast iron units but perhaps aluminum is not suited for, or ever used to build an exhaust manifold. I don't know so that's my question. Are exhaust manifolds ever cast out of aluminum instead of iron?
Chip
Gentlemen,
This is a topic about which I have zero knowledge or experience. I assumed, since the GT uses aluminum heads and block, that the exhaust manifolds would be cast aluminum as well. Aluminum would be lighter than the cast iron units but perhaps aluminum is not suited for, or ever used to build an exhaust manifold. I don't know so that's my question. Are exhaust manifolds ever cast out of aluminum instead of iron?
Chip
BlackICE
GT Owner
I didn't know the answer Chip, but I found some cast alumimum manifolds.
http://www.cpperformance.com/products/Exhaust/eickert-headers.htm
As Indy points out cast iron is used for it low cost, NHV, and robustness. Tubular headers can be made to last longer than we care about, but will be much more expensive and noisier. The construction of these shorties seem outstanding, but I wouldn't expect a huge performance increase from stock. Pluses, look cool, lighter, lower heat retention, maybe +20hp tops IMHO, compatible with all stock systems and parts.
http://www.cpperformance.com/products/Exhaust/eickert-headers.htm
As Indy points out cast iron is used for it low cost, NHV, and robustness. Tubular headers can be made to last longer than we care about, but will be much more expensive and noisier. The construction of these shorties seem outstanding, but I wouldn't expect a huge performance increase from stock. Pluses, look cool, lighter, lower heat retention, maybe +20hp tops IMHO, compatible with all stock systems and parts.
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sandman
GT Owner
The marine industry has been using aluminum exhaust manifolds (Hardin, Nicson, Gill and Eickert...) for years but the key is they are water jacketed. Their would be no advantage to doing this on a car.
The cast manifolds are strong, long lasting, able to handle heat and cost effective. The GT's exhaust manifold is also a pretty good design all things considered. It would have been very cool if the car came with a shorty header of some kind for aesthetics. I'm sure they would have been a major headache with ford dealers and owners who were less inclined to maintain them though.
The cast manifolds are strong, long lasting, able to handle heat and cost effective. The GT's exhaust manifold is also a pretty good design all things considered. It would have been very cool if the car came with a shorty header of some kind for aesthetics. I'm sure they would have been a major headache with ford dealers and owners who were less inclined to maintain them though.
Indy GT
Yea, I got one...too
Chip-
Most of the guys posting up have pretty much zeroed in on the shortcoming of aluminum exhaust manifolds. They just cannot take the sustained heat. Yes the heads and as a intergal part of the head the exhaust ports are all made from aluminum but there is a significant amount of engine coolant flowing around those passages to keep the metal temperture within reason. Same goes for the water jacketed marine manifolds which have an unlimited heat sink with the water in which the marine engine operates. I am certain the FGT team had cost as a design target in every component/system they designed, and the cast iron OE manifolds although maybe not the most glamorous could deliver the required performance (less asthetics) at a reasonable cost using a mature product.
Most of the guys posting up have pretty much zeroed in on the shortcoming of aluminum exhaust manifolds. They just cannot take the sustained heat. Yes the heads and as a intergal part of the head the exhaust ports are all made from aluminum but there is a significant amount of engine coolant flowing around those passages to keep the metal temperture within reason. Same goes for the water jacketed marine manifolds which have an unlimited heat sink with the water in which the marine engine operates. I am certain the FGT team had cost as a design target in every component/system they designed, and the cast iron OE manifolds although maybe not the most glamorous could deliver the required performance (less asthetics) at a reasonable cost using a mature product.
I guess when I asked the question about the manifold my mind was on Lamborghinis and Ferraris. I am sure the OE manifold is a fine piece of equipment. That manifold is also nicely covered up by the heat shields so nobody would know it's cast iron.
I plan on taking it to the dyno on Friday. I'll report the results immediately but I don't expect much +5 hp / -5 tqr. It was more for looks and braggin rights. :biggrin
I plan on taking it to the dyno on Friday. I'll report the results immediately but I don't expect much +5 hp / -5 tqr. It was more for looks and braggin rights. :biggrin
sandman
GT Owner
Your header design is very cool! I'm sure you'll have some gain, you already have the braggin rights so all is good!:thumbsup
Finally did a dyno to measure the change. It was much more than I expected. It looks like these headers may have added about 20hp though-out the entire power band.
We did the pull on the exact same machine as before. Also did three pulls at different engine temps. I will post pictures of the Dyno pull sheets later.
I am moving on to the next project now. :biggrin
PS: RacerX, that explains the results of our little test.
We did the pull on the exact same machine as before. Also did three pulls at different engine temps. I will post pictures of the Dyno pull sheets later.
I am moving on to the next project now. :biggrin
PS: RacerX, that explains the results of our little test.
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