H
HHGT
Guest
Thugboat
GT Owner
Last paragraph in Article.
""While 650hp in the new 5.8 beats the hell out of Chevrolet’s new 570hp ZL-1 by a huge margin in raw power, many Mustang enthusiasts will look at the new GT-500 as a baseline for more mods. The 5.4 engine has certainly proven its bulletproof capabilities in the past decade with many getting 800+ hp from them. We’ll see what the gurus of tune can do with this very soon.
They must know Torrie!!! LOL
Larry
""While 650hp in the new 5.8 beats the hell out of Chevrolet’s new 570hp ZL-1 by a huge margin in raw power, many Mustang enthusiasts will look at the new GT-500 as a baseline for more mods. The 5.4 engine has certainly proven its bulletproof capabilities in the past decade with many getting 800+ hp from them. We’ll see what the gurus of tune can do with this very soon.
They must know Torrie!!! LOL
Larry
H
HHGT
Guest
Looking at the exhaust manifolds on this engine seem really small and restrictive. Am I seeing things or one of the first modifications will be headers?
2112
Blue/white 06'
That's what people said about the Ford GT manifolds. Replacing the factory manifolds with headers is just about the worst "dollar per performance" mod you can make on a mod motor, which Mustang owners will be even more appreciative of.
Indy GT
Yea, I got one...too
2112, Dave is absolutely correct on this one.
Old wisdom always point hotrodders to add headers just, because....
And old exhaust manifold designs were not the best flowing designs so often adding headers did certainly increase engine breathing capability. But today, the designers have a number of numerical computer design codes (CFD, computational fluid dynamics) which they use very effectively to give free flowing designs which do not compromise engine performance. The exhaust manifolds on the FGT may not look as sexy as polished SS tubular headers, but they flow engine exhaust very well and do not hinder engine performance. As Dave points out, for the cost (and aggravation) of installing a set of headers on an FGT you will see little (if any) performance gain. Same with the new Boss short tube headers supplied OE on the 5.0 roadrunner engine. The design programs used today are so sophisticated that they also account for fluid temperature effects on viscosity such that design attributes can be incorporated in the intake/exhaust channels which would never be recognized using “cold” flow benches for design verification.
Don’t be so quick to judge these modern intake or exhaust systems based on old hotrodder experience.
Old wisdom always point hotrodders to add headers just, because....
And old exhaust manifold designs were not the best flowing designs so often adding headers did certainly increase engine breathing capability. But today, the designers have a number of numerical computer design codes (CFD, computational fluid dynamics) which they use very effectively to give free flowing designs which do not compromise engine performance. The exhaust manifolds on the FGT may not look as sexy as polished SS tubular headers, but they flow engine exhaust very well and do not hinder engine performance. As Dave points out, for the cost (and aggravation) of installing a set of headers on an FGT you will see little (if any) performance gain. Same with the new Boss short tube headers supplied OE on the 5.0 roadrunner engine. The design programs used today are so sophisticated that they also account for fluid temperature effects on viscosity such that design attributes can be incorporated in the intake/exhaust channels which would never be recognized using “cold” flow benches for design verification.
Don’t be so quick to judge these modern intake or exhaust systems based on old hotrodder experience.
Sinovac
GT Owner
The ARH 304 stainless headers for my GT500 cost about $1,700 and a pound of flesh (literally) for the install. All for a whopping 15-20 hp. But they look and sound cool. I would also add that supercharged motors in generally are less responsive to exhaust upgrades. If I had to do it over again, no headers for me.
There's no denying that if you're after the bad ass sound, they are worth it. They just aren't worth it for the horsepower, especially on cars that routinely gain twice as much power from a tune that costs 1/4 of the price.. I would also imagine that installing them in the stuffed engine bay of a Mustang would potentially be an even bigger pain in the ass than doing it on a Ford GT.
I have 3 sets of Kook's long tube headers being ceramic coated as we speak. As soon as we get these back, we will be installing on Boss 302 Coyote engines. I will do my best to get careful before and after dyno runs so that we can get an objective, real world look at what, if any, HP gains can be realized. One of the Coyote engine guys at Ford has stated publicly that long tube headers were not considered or tried during their own evaluations because the fundamental design of the long-tubes simply located the CAT too far away from the manifolds for their (emissions) consideration. This is precisely true when you look at the Kook's or American Racing headers for the Boss. The collector flange of these headers is located in space just about perfectly where the outlet flange of the OEM CAT is located. In 2 of the 3 set-ups that we are doing, we will have aftermarket hi-flo cats in the H-pipe immediately aft of the header collector. The third car will be cat-less. I will share the results as they are available - but I do expect SOME gains and I also would expect that the tuning of a long-tube header car can yield more HP gains than the tuning of a short-tube header OEM design. Might be wishful thinking!
Indy GT
Yea, I got one...too
Kendall glad to see you post up. Any reason you have avoided my inquiry about incorporating the Boss Track Key option on the Boss Mustangs which you maintain?
As a point of information, it is generally recognized the "Coyote" engine although of the same 5.0 liter family, is the engine designation for the Mustang GT, not the Boss which as you are well aware has significantly different engine internals (stronger for the higher rpm allowed by the Boss). The Boss 5.0 engine is known within Ford circles as the "Roadrunner" version of this 5.0 configuration.
It will be interesting to see the horsepower comparision between the two Mustang tests where the only variable is replacing the OE headers with the Kook's. But over in this Forum, the owners of FGT's should be aware of the differences between the two engine achitectures and not assume there is a one-to-one correlation between what you find and the expected gain for a FGT. The supercharged (sometimes supercharged and turbocharged) MOD 5.4L engine in the FGT has different exhaust flow characteristics than the normally asperated 5.0L Mustang engine. The exhaust piping system for a front engine vehicle is also different (the Boss has a unique 4-pipe exhaust system) than that used for a mid or rear enginened car. Pumping losses are different. Engine speed ranges are different as well all of which effect combustion chamber schavenging.
The comparisons will be interesting and I look forward to seeing the results of your testing.
As a point of information, it is generally recognized the "Coyote" engine although of the same 5.0 liter family, is the engine designation for the Mustang GT, not the Boss which as you are well aware has significantly different engine internals (stronger for the higher rpm allowed by the Boss). The Boss 5.0 engine is known within Ford circles as the "Roadrunner" version of this 5.0 configuration.
It will be interesting to see the horsepower comparision between the two Mustang tests where the only variable is replacing the OE headers with the Kook's. But over in this Forum, the owners of FGT's should be aware of the differences between the two engine achitectures and not assume there is a one-to-one correlation between what you find and the expected gain for a FGT. The supercharged (sometimes supercharged and turbocharged) MOD 5.4L engine in the FGT has different exhaust flow characteristics than the normally asperated 5.0L Mustang engine. The exhaust piping system for a front engine vehicle is also different (the Boss has a unique 4-pipe exhaust system) than that used for a mid or rear enginened car. Pumping losses are different. Engine speed ranges are different as well all of which effect combustion chamber schavenging.
The comparisons will be interesting and I look forward to seeing the results of your testing.
2112
Blue/white 06'
I am positive you are correct in you assessment.
For me, Even if there was zero performance gained, I would do it for the sound, esthetics and weight savings. :rolleyes
Sinovac
GT Owner
Sinovac
GT Owner
If you can, get a dyno reading with only a mid pipe and high flow cats. I would bet you gain more with the high flow cats than the headers.
H
HHGT
Guest
eek Man, I hope you aren't right!! The only good news here is that the wifee doesn't read these forums and know how frivolously I spend money!!
BlackICE
GT Owner
I bet you would gain more with no cats, vs. cats with headers. IMO some aftermarket "high flow" cats appear that they would flow worst than OEM.
Hey Indy, I didn't mean to ignore or avoid any questions - I must have missed it.... sorry!
Regarding the track keys, they are ordered and 2 of 3 came in and I just haven't had the time to get the cars to the dealership for programming. My car is still at the fabricator who is working on the roll bar. On Kelvin's car, I just need to get a break from work and get it over there. I heard that Terry's dealer successfully ordered the track key and it should be in this week.
Agree. Once upon a time I had the FRPP long tube headers on my GT and it has OEM manifolds now. Enough said. However, I have personally seen some dynos of the 5.0 engine showing impressive gains on the long tube headers. We'll know soon. I'll share, good or bad.
When looking to exact the best performance, remember that the key is Power/Weight ratio. The cast iron OEM exhausts of the GT, and the associated flanges of the OEM CAT systerm are quite heavy compared to the rear exit headers. I'm assuming that both systems get rid of the OEM boat anchor muffler.
On the heavier Mustangs, this may not be as great a performance factor, but it is nevertheless an improvement.
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