Is 4.6L Superior to 5.4L
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From: Ruckersville VA
Tritonpwr.... In your mustang is what motor? Sorry I forget. You evidently have quality parts in it to be making that much power. If it is the 5.4, and you built a 4.6 EXACTLY like it, same number of valves, same compression ratio, ect ect. How much more horsepower and torque would the 5.4 have if you had to take a guess? Thanks buddy 
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From: Texass
Originally Posted by jbravo316
Tritonpwr.... In your mustang is what motor? Sorry I forget. You evidently have quality parts in it to be making that much power. If it is the 5.4, and you built a 4.6 EXACTLY like it, same number of valves, same compression ratio, ect ect. How much more horsepower and torque would the 5.4 have if you had to take a guess? Thanks buddy
First of all, you wouldn't want them to be built exactly the same. The amount of air moved per stroke has to be taken into account when you pick the port cc, the valve size, cam profile, runner length, etc. Since the 5.4 has to move more air, you would want a larger port, bigger valves, more aggressive cam, etc.
IF both engine were built as efficient as possible, the 5.4 would make 17% more horsepower and torque. If the 4.6 made 400hp, the 5.4 would only make 468hp. But, if you build them both the same, the engine will be more efficient for 4.6 liters of displacement, or 5.4, not both. If the engine is designed for 4.6, and you run 5.4, the percentage falls. With that, 5%, 10%, etc. would be a good guess. Likewise, if you build it to support 5.4 liters, that same configuration with only 4.6 liters would suffer because it would have to spin faster to move the same amount of air.
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From: Palm Bay
the reason the 5.4 is more powerful then the 4.6 is the extra displacement.
the reason the 3V 5.4 is more powerful then the 4.6 3V is because of the extra displacement..
theres no replacement for displacement
and it sounds like the 5.4 is a heavier duty engine.. having the steel crank and what not..
like its been said if you bolt on identical mods to each engine the 5.4 will always have more power..
so ya like someone here said.. ford should simply get rid of the 4.6 and squeeze everything they can out of the 5.4 ..
or go ahead with the new BOSS 6.2L
rumors abound about that engine and its capabilities. last i read its going to put out 425hp and 425 trq and has the potential to be bored to a 7.0L 
we will see whats what in 2008
but as was said for the 6.4L PSD.. i'll believe it when i see it..
the reason the 3V 5.4 is more powerful then the 4.6 3V is because of the extra displacement..
theres no replacement for displacement
and it sounds like the 5.4 is a heavier duty engine.. having the steel crank and what not..
like its been said if you bolt on identical mods to each engine the 5.4 will always have more power..
so ya like someone here said.. ford should simply get rid of the 4.6 and squeeze everything they can out of the 5.4 ..
or go ahead with the new BOSS 6.2L
rumors abound about that engine and its capabilities. last i read its going to put out 425hp and 425 trq and has the potential to be bored to a 7.0L we will see whats what in 2008
but as was said for the 6.4L PSD.. i'll believe it when i see it..
Technical Article Contributor
Joined: Oct 2005
Posts: 25,641
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From: MI
Originally Posted by tritonpwr
wtf
Well, I sort of expect that kind of nonsense from a mac user.
Well, I sort of expect that kind of nonsense from a mac user.
Hey Pipe down pal!! hahh! I'm just using it now because I'm breaking the keyboard in - the office has a MAC and PC side by side for testing.
I use the mac for f150 online when it comes to uploading photos - with MACS Automator it takes the photo right to f150''s album and throws up a link to include in a message .
Will the PC do that - RIGHT!! Well when Vista gets here (I'm the only one who doesn't have it - it seams ) We'll see if that can beat it . I seriously doubt it , MAC hard to beat when it comes to vid and photo formatting.
Put that in your pipe
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Joined: Oct 2005
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From: Palm Bay
Originally Posted by tritonpwr
It's a 427 built with a Dart block from Kuntz and Co, somewhat like a stroked 351, but 100% custom and aftermarket.
First of all, you wouldn't want them to be built exactly the same. The amount of air moved per stroke has to be taken into account when you pick the port cc, the valve size, cam profile, runner length, etc. Since the 5.4 has to move more air, you would want a larger port, bigger valves, more aggressive cam, etc.
IF both engine were built as efficient as possible, the 5.4 would make 17% more horsepower and torque. If the 4.6 made 400hp, the 5.4 would only make 468hp. But, if you build them both the same, the engine will be more efficient for 4.6 liters of displacement, or 5.4, not both. If the engine is designed for 4.6, and you run 5.4, the percentage falls. With that, 5%, 10%, etc. would be a good guess. Likewise, if you build it to support 5.4 liters, that same configuration with only 4.6 liters would suffer because it would have to spin faster to move the same amount of air.
First of all, you wouldn't want them to be built exactly the same. The amount of air moved per stroke has to be taken into account when you pick the port cc, the valve size, cam profile, runner length, etc. Since the 5.4 has to move more air, you would want a larger port, bigger valves, more aggressive cam, etc.
IF both engine were built as efficient as possible, the 5.4 would make 17% more horsepower and torque. If the 4.6 made 400hp, the 5.4 would only make 468hp. But, if you build them both the same, the engine will be more efficient for 4.6 liters of displacement, or 5.4, not both. If the engine is designed for 4.6, and you run 5.4, the percentage falls. With that, 5%, 10%, etc. would be a good guess. Likewise, if you build it to support 5.4 liters, that same configuration with only 4.6 liters would suffer because it would have to spin faster to move the same amount of air.
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Joined: Oct 2003
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From: Washington
Originally Posted by jbravo316
Klitch... I can only speak from personal experience, but just because someone can build a chevy 350, doesn't mean thay can build these modular motors and get them to stay together like they should. Example.. Neal, and the first guy who screwed up the motor that was in my truck. Not saying that you can't do it, just saying it aint as easy as it is with other motors. I could have had the motor that is going in my truck built around where I live for half of what it cost me, but at least I know it's done right.
i have already gathered the mod motors are harder to build. i shall learn why.
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Joined: Oct 2005
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From: Palm Bay
Originally Posted by Klitch
well yes i can see that, but i would rather LEARN it myself than pay someone down town this area that truly dont know a modular and is just looking for a paycheck. if i do mess it up, it will be a very harsh lesson i know. but i'd rather do it than have this unmentionable furious rage bottle up towards someone saying they can do it and F it all up.
i have already gathered the mod motors are harder to build. i shall learn why.
i have already gathered the mod motors are harder to build. i shall learn why.
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Joined: Oct 2003
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From: Washington
Originally Posted by UberDude
you going with a 2v or 3v 5.4?
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From: Palm Bay
Originally Posted by Klitch
complete engine i have coming to tear apart was an 02, so 2v atm. unless i can find a way to go 3v w/o paying a lot of money for the head work / swap deal. as it stands im lookin at 1800 for the exchange thru fox lake.
thats not bad.
o well, you'll certainly put my stock 5.43v in its place
not that thats hard to do.
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Joined: Oct 2005
Posts: 25,641
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From: MI
Originally Posted by royalblue150
P.S. I'll run my "little" non-pi 4.6 against any 5.4 out there.
Another crazy , You can mod it to the hilt , I still would grab the holeshot , you might pass me - depends on your mods , but I'm stock LOL .
Gee , why spend the big bucks moding a 4.6 . If my stock 5.4L can still beat you out of the hole , Whats that make your 4.6 worth?
Just seams like a waste of time and money.