Shelby 5.4L Versus Roush supercharged 5.0L
10-22-2011, 05:12 PM
#1
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Shelby 5.4L Versus Roush supercharged 5.0L
Shelby 5.4L Versus Roush supercharged 5.0L
I'm not trying to offend any Shelby owners here... so please don't get defensive!
I'm just trying to get some understanding about the GT 500 5.4L supercharged engine versus the Roush Supercharged 2012 5.0L. I'm considering buying either: a new Shelby GT 500, or a new 5.0L, 6 spd & putting a Roush supercharger on it which would run at least substantially less! So I'm looking for the pros & cons of each purchase. The Shelby has better resale, but I'll probably have $12 to $14K more invested in it to retrieve if I sell it! I love Shelby's 
... but I doubt Carroll Shelby is very concerned about my life or bank account... so I won't worry about his signature on my car! I suspect he has enough money to slide by!
The 2012 Shelby GT 500's supercharged 5.4L is rated at "550" HP.
The 2012 5.0L with a Roush supercharger is rated at "540" HP.
It seems the 5.4L supercharged should be pushing 600 HP based on displacement... apples to apples it produced horsepower as well as the 5.0L... right? Off the top of my head... I believe the 5.4L supercharger is running much lower PSI than the Roush supercharger being put on the new 5.0L... correct? If so, will the 5.4L take the higher PSI they are running in the new 5.0L without having a problem? My '08 4.6L has a Roush supercharger on it & I have compared it to quite a few '08 Gt 500's with the 5.4L engine & my 4.6L supercharged compares very well! It has much less torque off the line, but it pulls 0 to 60 comparibly according to my stopwatch. It also gets 27.5 MPG on trips which doesn't hurt!
Question:
Is the 5.4L detuned for warranty purposes, or doesn't the 5.4L engine produce horsepower as well as the 5.0L... apples to apples?? Inquiring minds want to know before they spend a bunch of money on a new Mustang!
Opinions "without hand grenades" are welcome!
I'm not trying to offend any Shelby owners here... so please don't get defensive!
I'm just trying to get some understanding about the GT 500 5.4L supercharged engine versus the Roush Supercharged 2012 5.0L. I'm considering buying either: a new Shelby GT 500, or a new 5.0L, 6 spd & putting a Roush supercharger on it which would run at least substantially less! So I'm looking for the pros & cons of each purchase. The Shelby has better resale, but I'll probably have $12 to $14K more invested in it to retrieve if I sell it! I love Shelby's ... but I doubt Carroll Shelby is very concerned about my life or bank account... so I won't worry about his signature on my car! I suspect he has enough money to slide by! The 2012 Shelby GT 500's supercharged 5.4L is rated at "550" HP.
The 2012 5.0L with a Roush supercharger is rated at "540" HP.
It seems the 5.4L supercharged should be pushing 600 HP based on displacement... apples to apples it produced horsepower as well as the 5.0L... right? Off the top of my head... I believe the 5.4L supercharger is running much lower PSI than the Roush supercharger being put on the new 5.0L... correct? If so, will the 5.4L take the higher PSI they are running in the new 5.0L without having a problem? My '08 4.6L has a Roush supercharger on it & I have compared it to quite a few '08 Gt 500's with the 5.4L engine & my 4.6L supercharged compares very well! It has much less torque off the line, but it pulls 0 to 60 comparibly according to my stopwatch. It also gets 27.5 MPG on trips which doesn't hurt!
Question:
Is the 5.4L detuned for warranty purposes, or doesn't the 5.4L engine produce horsepower as well as the 5.0L... apples to apples?? Inquiring minds want to know before they spend a bunch of money on a new Mustang!
Opinions "without hand grenades" are welcome!
Last edited by Mr. D; 10-22-2011 at 05:45 PM.
10-23-2011, 08:09 PM
#2
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Just found that the 2011 5.4L has 9 PSI boost! Now, I'm confused as to why it only puts out 10 more HP than the supercharged 5.0L which has 8% less cubic inches! Variable valve timing... engine design... what?
10-24-2011, 05:44 PM
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I'm comparing the 5.4L & the 5.0L before I change Mustangs! I remember seeing a special where they took a close look at the variable valve tiiming setup with the cams of the 5.0L. It looked pretty sophisticated. It may just be a more efficient engine than the 5.4L. I'm just trying to figure out the potential of the 5.4L, because the older ones like '07 & '08 aren't that much more than the supercharged 4.6L I'm driving. Much more bottom end torque... but not much faster overall! I looked at two really nice '08's to buy, but after driving them I didn't think I was gaining much other than a stiffer ride!
10-24-2011, 06:08 PM
#5
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the gt500=bigger displacement, smaller supercharger, less CR.
the coyote roush = smaller displacement, bigger SC, more CR.
the CR is the biggest factor in why the coyote makes big power from little boost.
if price is not limitation, go with the shelby. better motor, more potential for more power.
you could easily make a load of power with your 08 also.
the coyote roush = smaller displacement, bigger SC, more CR.
the CR is the biggest factor in why the coyote makes big power from little boost.
if price is not limitation, go with the shelby. better motor, more potential for more power.
you could easily make a load of power with your 08 also.
10-24-2011, 10:30 PM
#6
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Give me your reasoning as to why the 5.4L is a better choice price aside. Give specifics if possible. How is your Coyote Rush evaluated in something we can actually measure" I've heard of HP & Torque, but what are you measuring when you refer to Coyote Rush or..... how about Mustang March???
Last edited by Mr. D; 10-24-2011 at 10:33 PM.
10-25-2011, 04:29 PM
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Give me your reasoning as to why the 5.4L is a better choice price aside. Give specifics if possible. How is your Coyote Rush evaluated in something we can actually measure" I've heard of HP & Torque, but what are you measuring when you refer to Coyote Rush or..... how about Mustang March???
the GT500 is a better car overall.
better engine, better tranny, better clutch.
it is Coyote Roush , not Rush. and idk what Mustang March is.
the coyote motor will only take so much abuse, the GT500 5.4L will take more.
the GT500 is already built to take more hp
A Roush SC'd GT, will not take the punishment a GT500 can without further upgrades
you must look at more than just hp and tq.
sure thats what sells cars, and thats why ford upped the CR in the coyote motor, to make more power and sell Mustangs.
thats why the CR is less in the GT500, it is built for boost. the coyote motor is not.
if you are going to build up a GT, you might as well keep your 08 and build that.
10-25-2011, 06:54 PM
#8
From what I've heard,
a CAI and tune on a GT500 can add 100hp? I may be wrong on that...but in that case, it puts it above the supercharged coyote.,
Also, the GT500 has a built engine, capable of handling at least 200 more horses than it comes with factory...(Again something I've heard, not 100% on that..)
If you wanted to put out 700 hp on the Coyote you'd be looking at building the engine, which can be just as pricey..not to mention the tuning, etc, associated with going FI on the 5.0.
Let's not forget the multiple issues found with the manual tranny on the 5.0. (haven't really heard any bad things about the gt500..)
a CAI and tune on a GT500 can add 100hp? I may be wrong on that...but in that case, it puts it above the supercharged coyote.,
Also, the GT500 has a built engine, capable of handling at least 200 more horses than it comes with factory...(Again something I've heard, not 100% on that..)
If you wanted to put out 700 hp on the Coyote you'd be looking at building the engine, which can be just as pricey..not to mention the tuning, etc, associated with going FI on the 5.0.
Let's not forget the multiple issues found with the manual tranny on the 5.0. (haven't really heard any bad things about the gt500..)
10-25-2011, 07:32 PM
#9
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Ok ... To add to this with some facts on a gt500 from personal experience.. Of course you can always build a faster car.. So this is not about that only.. The gt500 platform is built for power safely to 800hp or there abouts...many have there gt500 on stock parts pushing 700++ rwhp and over 700tq...
A simple CAI and tune with pulley change will get you 110-130 Rwhp ... A supercharger change (like I did) with the stock TB; stock injectors vmp TVS and I am at over 765 hp or 677 Rwhp and 666 torque on a 100 degree day with 17lbs of boost...all on my daily driver with no issue and fuel duty cycles still within safe limits!!! So I do think the gt500 platform is stronger to begin with...
A simple CAI and tune with pulley change will get you 110-130 Rwhp ... A supercharger change (like I did) with the stock TB; stock injectors vmp TVS and I am at over 765 hp or 677 Rwhp and 666 torque on a 100 degree day with 17lbs of boost...all on my daily driver with no issue and fuel duty cycles still within safe limits!!! So I do think the gt500 platform is stronger to begin with...
10-25-2011, 08:43 PM
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I found out one thing that enters into the question of whether to buy a GT 500 or a standard Mustang GT 5.0L & add a Roush Supercharger.... the attitude of stealerships! I checked on pricing today & was treated as if I should feel "Oh so lucky... if a dealer would lowerer itself to sell me a Shelby GT 500 FOR ...ONLY... FULL STICKER PRICE" without adding extra markup to the price! I've got your full sticker price right here! Maybe if I'm really polite they let me give them $50K! I thought I was talking to his highness Carroll Shelby & half those salesmen can barely tell you how many wheels the car has! Based on that stinking attitude I faced at two dealers, I'll probably buy a 5.0L six speed & put a Roush supercharger on it saving myself a ton of money for things I really don't want anyway!
I also loved it when I asked some questions of the Service Manager that he told me they don't get that information! (The tough question was: "Are the pistons of a 5.4L forged?) When I told him it was probably in his Ford literature he told me he didn't want to argue with me! Nice treatment... when you are buying a $50K car! Evidently asking about specs on the 5.4L engine is arguing! I would have accepted a simple, "I don't know!" I've often wondered if employees at auto dealerships & gun shops are asked "Are you an *******?" during their employment interviews... & if they say "No, I'm not a *******!" ... they are not hired! I wonder if there's a way I can buy a new Mustang from my Toyota dealer??? I love Mustangs... but Ford Dealers not so much!!
I also loved it when I asked some questions of the Service Manager that he told me they don't get that information! (The tough question was: "Are the pistons of a 5.4L forged?) When I told him it was probably in his Ford literature he told me he didn't want to argue with me! Nice treatment... when you are buying a $50K car! Evidently asking about specs on the 5.4L engine is arguing! I would have accepted a simple, "I don't know!" I've often wondered if employees at auto dealerships & gun shops are asked "Are you an *******?" during their employment interviews... & if they say "No, I'm not a *******!" ... they are not hired! I wonder if there's a way I can buy a new Mustang from my Toyota dealer??? I love Mustangs... but Ford Dealers not so much!!
Last edited by Mr. D; 10-25-2011 at 08:48 PM.