Supercharger for the 07 auto?

[strawberrytetra]

My husband called Quantum Performance and the guy there said there is no supercharger kit for the 07 autos. Please advise why?

[Son of GT]

That makes no sense. The white car pictured in my signature is an 07 with an automatic and a Paxton supercharger. The 2008 cars are still waiting for a C.A.R.B. approval for specific supercharger applications, but not the 2007's. Perhaps the person at Quantum thought that your car was a 2008.

 

I would contact Bud at Shelby Autos; he should be able to resolve the confusion for you.

[strawberrytetra]

I am wondering if it was because we asked about the Kenne Bell then. My husband was mainly asking because we weren't sure which sc to go with that would work best with the auto. The guy at Quantum also said the Kenne Bell kit will work on the 08 auto but not the 07 as of yet.

[pottydr]

I have a KB and I also have the automatic, 2007, Rick

[Budman340]

On the 07 automatics, you now have 2 choices. You can go with the 460hp (at the crank) Paxton or the 500 hp (rear wheels) Kenne Bell. The Shelby Paxton set up is availible now. The Shelby Kenne Bell will be availible soon.

 

Bud

[RogerS]

Thanks Bud.

[strawberrytetra]

Thank you Bud.

[68fastback]

Not meaning to rain on anyone's parade but 500rw is about 585 at the crank ...on the 4.6's cast crank and a relatively unreinforced alloy mod block. I know, I know ...many have pushed the 4.6 farther, but just wanted to go on record that that's pushing the envelope on the 4.6 3V ...really pushing it. The big low-end torque of a fixed displacement s/c like the KB puts even more twisting stress on the block than the HP number implies too -- stresses the 4.6 was not designed to live long with. Not nearly as much problem with the Paxton centrifugal (HP numbers aside). Maybe with street tires it won't matter, but I sure would not track a 4.6 3V with a KB at 585crank with slicks! ...just my .02.

 

Dan

[RACERX009]

Hey guys and gals I agree with Dan the 4.6 is not a motor to push to it's limits unless you are going to be drag racing for pinks or being chased by Mad Max. It's not like 15yrs ago when you can street race or do 1,000 mls an hour on the highway and talk your way out of a ticket. Today days and times they will take your car and sell and still make you pay a huge fine. That's why no S/C for me maybe a Cam set and whatever else that won't get me arrested or worse. With Great Power Comes Great Responsibility !!!!!

 

2007 Shelby Mustang Gt

2008 Ford Expedition EL

 

1986 Lincoln auto Tech

3yrs F.B.I automotive Tech

8yrs Ford mechanic

14yrs NYPD P.O {disability retirement 9/11}

[Son of GT]

Not meaning to rain on anyone's parade but 500rw is about 585 at the crank ...on the 4.6's cast crank and a relatively unreinforced alloy mod block. I know, I know ...many have pushed the 4.6 farther, but just wanted to go on record that that's pushing the envelope on the 4.6 3V ...really pushing it. The big low-end torque of a fixed displacement s/c like the KB puts even more twisting stress on the block than the HP number implies too -- stresses the 4.6 was not designed to live long with. Not nearly as much problem with the Paxton centrifugal (HP numbers aside). Maybe with street tires it won't matter, but I sure would not track a 4.6 3V with a KB at 585crank with slicks! ...just my .02.

 

Dan

I see your .02 cents and add my .02 cents...you are 100% right my friend!

[LuLu]

On the 07 automatics, you now have 2 choices. You can go with the 460hp (at the crank) Paxton or the 500 hp (rear wheels) Kenne Bell. The Shelby Paxton set up is availible now. The Shelby Kenne Bell will be availible soon.

 

Bud

500 RWHP from an auto tranny car (suffering a 25% loss of power from torque leaks in the drive train), is IMHO, risky for the stock 4.6L-3V engine AND 5R55S auto tranny. Been here, did this with a 4V DOHC 4.6L, and the 4R70W auto tranny.

 

RWHP is not the performance index I follow. RW torque is the key to a fast car, and it's RWTQ that will tear up a drive train. But, it's the index y'all keep calling upon, so, IMHO, 500 RWHP will produce 475+ RWTQ, and something will break. Time will tell.

 

Just my .02C on it.

[SGT2666]

500 RWHP from an auto tranny car (suffering a 25% loss of power from torque leaks in the drive train), is IMHO, risky for the stock 4.6L-3V engine AND 5R55S auto tranny. Been here, did this with a 4V DOHC 4.6L, and the 4R70W auto tranny.

 

RWHP is not the performance index I follow. RW torque is the key to a fast car, and it's RWTQ that will tear up a drive train. But, it's the index y'all keep calling upon, so, IMHO, 500 RWHP will produce 475+ RWTQ, and something will break. Time will tell.

 

Just my .02C on it.

 

Since dyno's really only measure torque and calculate hp they are kind of tied at the hip aren't they?

[RogerS]

Seen it happen with less than that. -_-

[strawberrytetra]

Then would it be safe to assume that if I get my supercharger I would be better off with the paxton? I tend to have a lead foot and don't want to f**k up my car.

[LuLu]

Since dyno's really only measure torque and calculate hp they are kind of tied at the hip aren't they?

This really is another discussion, 2666, I wish you had opened a new thread. Oh well, here we go?

 

Indeed the numbers are related, my friend. Your are correct, but as the real power index, torque comes on first while HP follows the torque curve. With some mods which seem to be popular here, you can gain HP and lose torque.

 

Yes, it's true. Add a mod that has been reported to improve HP to some X degree, and you may lose torque. This means that once off the dyno and back on the street, you may be disappointed with your results in moving the car forward. It's the difference between being fast and quick, eh?

 

Evaluating overall performance strictly by RWHP (and in many cases stated here, brake/flywheel horsepower), is (IMHO) not the best way to evaluate. I suppose we like the larger numbers? Any way...When building power, watch (and build) torque. Not only at the rear wheels, but throughout the power curve. Do not be so dependent on (or, proud of?) the final numbers at the end of the dyno pull, as aluring as those number may be. Though torque may produce high horsepower numbers, the torque it takes to produce those numbers on the street is what tears up the hardware too, which is my specific point.

 

Sideline...The home stereo/audio industry went through this many, many years ago while trying to evaluate what advertised power output numbers count. The manfacturer did this to us. They started the question themselves when claims of "overall performance power" reached into the 4 and 5 digit numbers. This continues today with some products, but 12 watts of audio power times 4 speakers, is still 48 watts of power under the RMS rule. So, the "Shaker 1000" audio system does not mean that you bought 1000 watts of audio power, follow me? Finally, there came an agreement to the RMS standard (which is much like an S.A.E. adjustment to dyno numbers). Thus, is you are buying a new home stereo/audio (now called home theater) system, the bottom line is genuine audio "torque"...Actuall RMS ratings. The higher the RMS rating, the better the sound, and from less amp heat and electricity consumption.

 

It's the same scenario here. While auto mags/rags and manfacturers focus on bragging about brake/flywheel horsepower and brake torque for the higher/better numbers (read = no load), it's not the genuine/actual index of rear wheel power that consumers will see/feel on the street. Again, it's RWTQ that moves the car against the wind and against the drag of the road, not BHP, or, BTQ. Dyno RWHP is a good place to start, but it's dyno RWTQ that you should be watching most.

 

Trying to get back on topic...If a supercharger kit (as discussed here) makes 500+ RWHP with an auto-tranny in the drive line, this RWTQ has to be in that same neighborhood and it's one dangerous neighborhood to drive through with stock components in play. Backward calculate what it takes to produce 500+ RWHP through a 25% loss of drive line torque and things should begin to come clear. That neighborhood begs too much of the stock 4.6L-3V engine, and stock 5R55S auto tranny, things will break.

 

I don't mean to offend anyone, but if you own a garage/trailer SGT, I expect all will be well. But, if you intend to hammer your SGT daily, even semi-daily as a "weekend racer", keep your checkbook at your finger tips? I routinely hammer my SGT. Guess I'm not so popular here because of that...

 

Just my .02C gents, happy motoring...

[68fastback]

Then would it be safe to assume that if I get my supercharger I would be better off with the paxton? I tend to have a lead foot and don't want to f**k up my car.

 

There are a lot of Paxtons and Vortech's on the 4.6 alloy 3V in the 450-480rwHP range and they seem to be holding up well. These are centrifugal (not fixed displacement) designs that build torque more like a turbo in that they tend to spool-up more gradually and therefore stress the engine less, imo ...a consideration on a non-forged motor at high outpuit, imo. In essence centrifugals are belt/gear-driving turbos.

 

Another way to think of it: even if the Paxton makes the same *peak* rwHP and *peak* torque as a fixed-disp s/c, since it's peak is 'peakier' and at higher rpm, that peak energy is spread over more power-strokes (more revolutions/unit-of-time) so the block-distorting twisting stresses are reduced. The 'downside' is that with the Paxton you need to be more on your game to keep the engine in it's sweet spot (less low-end torque) to get similar peformance than with the big low-end grunt of a fixed disp s/c like the KB, but the 'upside' is that it's a bit harder to hurt the engine (all other things being equal and they never are <lol>) since there is less grunt at the low-end.

 

To draw an analogy (not literally): the Paxton/Vortech will feel like a hi-po NA motor that needs revs to spool-up torque and, because tranny gear-spacing is a given, wants the driver to match gear selection to the peak-power band for best results, whereas the KB will feel more like a larger displacement motor's broad/flat torque curve which is more forgiving to driver not power-band-matching the gears but less forgiving to the engine when not spreading torque over more power-strokes/sec (rpm).

 

Short version: the Paxton will take a bit more driver skill to get comparable performance (for an equivalent output level, all things being equal) because it's design precludes big low-end torque but will stress the motor less as a result ...if that makes sense.

 

So, if you're going to push up above 450rwHP, I'd go with the Paxton/Vortech on the stock alloy 4.6 3V since it makes it a bit more difficult to break things. If the 4.6 had forged internals or you were doing a built motor then I'd pick a fixed-disp S/C because it would then be safer to also use the big low-end grunt.

 

Sorry for the long post ...hard to know if the words are working...

 

Dan

[64peter]

Hey guys and gals I agree with Dan the 4.6 is not a motor to push to it's limits unless you are going to be drag racing for pinks or being chased by Mad Max. It's not like 15yrs ago when you can street race or do 1,000 mls an hour on the highway and talk your way out of a ticket. Today days and times they will take your car and sell and still make you pay a huge fine. That's why no S/C for me maybe a Cam set and whatever else that won't get me arrested or worse. With Great Power Comes Great Responsibility !!!!!

 

2007 Shelby Mustang Gt

2008 Ford Expedition EL

 

1986 Lincoln auto Tech

3yrs F.B.I automotive Tech

8yrs Ford mechanic

14yrs NYPD P.O {disability retirement 9/11}

 

 

Are those Shelby Quarter Window Scoops ? They look great.

( Sorry to change the suject )

 

Pete.

[strawberrytetra]

Thank you to all of you guys I understand it much better now. How much stress do I want to create when I get on it is the new question. And if I want to get on it like that then how much money am I willing to spend to make it so I don't break the car. I think I am going to learn some more before I make those decisions.

 

Candi

[Cobramach1]

My biggest question in regards to this thread is whether the 5r55s trans will hold up to a supercharger in stock form? I've heard they are kind of weak in comparison to the 4r70w/4r75w transmissions mostly because the 3rd and 4th gear are synchronously shifted. Has anyone had any problems regarding this with a supercharger on their car and have they had it down a dragstrip under true WOT conditions?

[LuLu]

...So, if you're going to push up above 450rwHP, I'd go with the Paxton/Vortech on the stock alloy 4.6 3V since it makes it a bit more difficult to break things. If the 4.6 had forged internals or you were doing a built motor then I'd pick a fixed-disp S/C because it would then be safer to also use the big low-end grunt.

 

Sorry for the long post ...hard to know if the words are working...

 

Dan

Candi...I don't disagree with what Dan has posted, but IMHO, it's not a matter of when the power comes on (at any specific RPM, or how quickly it builds) but how much total power you're pushing through the engine.

 

The Paxton/Vortech kit Dan mentions is often thought of as a softer approach to supercharging, but it is no slouch at the tree. The kit employs a Novi 1200 blower head and simply by changing the drive pulley, you can push 12-14 PSI of boost without stressing the blower. A Vortech T trim can pulley down to 16-18 PSI of boost, no sweat for the blower.

 

However, these levels of boost are dangerous territories for the stock SGT engine and tranny, way beyond their design limitations and this level of power won't be healthy for stock components. Which ever kit you choose, keep the boost at or under 8 PSI and you should have a lot of fun. 10 PSI is borderline and long term wear and tear will accumulate. More than 10 PSI will will impact longevity of both the engine and the tranny, moreso if you drive the car hard.

 

My biggest question in regards to this thread is whether the 5r55s trans will hold up to a supercharger in stock form? I've heard they are kind of weak in comparison to the 4r70w/4r75w transmissions mostly because the 3rd and 4th gear are synchronously shifted. Has anyone had any problems regarding this with a supercharger on their car and have they had it down a dragstrip under true WOT conditions?

I've had some experience with building power on a stock 4R70W tranny, and it won't hold up over 500 RWHP in it's stock form. It needs to be built for the task, start with the torque converter. I have no true experience with the 5R55S auto tranny, but I presume it's likewise limited in durability. Remember, 500 RWHP is almost double the power of the original design.

 

Folks...The stock Mustang GT/SGT is a very durable car. The powertrain components are very well designed and quality control has been impressive to me. However, the design and engineering behind it presents limitations to building power and I believe this limitation is 450 RWHP/450 RWTQ no matter what power adder you install. More power than that can be had, that's easy with a pulley change and re-tune. But, y'all need to fortify the engine and tranny, or, suffer the consequences of pushing the stock components too far.

 

Just my .02C, happy motoring!

['07 SGT 2289]

I spoke to Whipple at length about this issue. I was going to put a larger pull on the HO system to drop the boost to 8 psi. They told me that they have NEVER lost the lower end of a motor @ 10 lbs. He said stay with their program and that I would be safe. Great system.

[69dejavue]

Maybe Whipple never lost a motor but you might and you have to pay, not Whipple. Remember that a supercharger's increase in power is directly related to boost. One Bar is about 14.7. So, if you ran 14.7 pounds of boost, without any parasititc losses, you would increase horsepower by 100%. Hypothetically about 5 pounds of boost would equal about 33% or about an additional 106 to our 319. So at 5 pounds of boost approximately 425 HP (flywheel). Same as the big block hemi and chevy. Less weight. And at 5 pounds it should live forever. Sounds like a plan. 8 pounds is going to break someday and you will have lots of shiny metal pieces internally. 10+ is like pulling the pin on a hand grenade and wondering how long you can hold the pineapple. Someday you will tire and so will the engine. Say good night Irene! I plan on a Paxton in the future with about 5-6 pounds boost max.You have to have discipline and an engine, just like a man- in Clint Eastwood's terms- a man has got to know his limitations. A stock powdered rods, cast crank motor has limitations. At 500 HP sooner or later something is going to break in the drive train. Remember this is the same rods and crank as in Grandma's Crown Vic. Have discipline

['07 SGT 2289]

You speak the truth, I drive my car two or three times a month. After the new wears off I will put the 8 lb pulley on it. If I want to mess with a GT 500, I will borrow my wife's C63 AMG.

[LuLu]

I spoke to Whipple at length about this issue. I was going to put a larger pull on the HO system to drop the boost to 8 psi. They told me that they have NEVER lost the lower end of a motor @ 10 lbs. He said stay with their program and that I would be safe. Great system.

Makes me want to ask how many Whipple blowers are on the street today, on 4.6L-X engines and getting hammered hard? Stats...They can tell any story you want. Nevermind, I won't go there.

 

Anyone here at SGT/TS considering supercharging (or turbocharging for that matter) needs to brush up on the history of the 4.6L-3V used in our base Mustang GT application.

 

The truth is that at or above 500 RWHP, the stock bottom end is "twitchy" to say the least. What you can get away with on one stout engine will window the block of the next engine off the production line. Maybe no one here has yet to suffer a catastrophic failure (makes me wonder if they would 'fess up to begin with), but we remain a small and somewhat "closed" community because it's all about a Shelby. Thus, among us Shelby owners, Whipple's claim is most likely a true statement. Just give it all some time?

 

Interesting discovery...I went back to my FRP catalogues through 2003, only to learn that just a few years ago, there was no Whipple blower kit of any sort offered for FMC products at all.

 

Back then, FRP offered a Vortech SL trim kit pushing 6 PSI for the 5.0L pushrod engine. FRP also offered an Eaton 112 CID (largest CID blower Eaton makes) based kit (again @ 6 PSI) for the F-150+ fans with a modular SOHC engine, as well as offering a Jackson Racing kit employing the Eaton "Gen III" 45 CID blower for the Focus ZX3 2.0L Zetech 4. Likewise, same offerings in 2004's catalogue.

 

Whipple appeared in 2005 as an upgrade to 2003-04 Mustang GTs with the 4.6L-2V engine. Again, (IMHO) with a conservative boost of 6 PSI, and with a strong disclaimer of "installation of this kit will void your new car factory warranty". In 2006 and 2007, same offerings. Same blowers with the same boost, for the same engines, and with the same cautions. 2006 and 2007 were lame IMHO, and just adding a polished appearance option.

 

In the 2008 FRP catalogue, things from FRP changed, adding upgrades for the stock GT 500 factory supercharged application, as well as adding the option of intercooling (a must have IMHO). However, boost offered was reduced to 5 PSI...Interesting? I think so...

 

My point is...Step out into the real world and you will find broken 4.6L engines everywhere, and only because owners pushed the power limits by increasing boost. Vortech has been selling blower kits for the 4.6L engine for over 11 years and there are thousands of Vortech blowers in the wild. How long (rather, how many?) have Whipple blowers been in the wild?

 

Honestly, car for car (at the race track mind you), I've seen noticed that Kenne Bell blowers are "inching up" on the Vortect/Paxton kits present there for years. I have yet to see one Whipple blower face to snout.

 

This is "market presence", and IMHO, Whipple doesn't have a lot of "seat time" in the real world. Again, this fortifies Whipple's claim, but peel back a layer or two? How long has Whipple been in the market? How much field testing has filtered back to Whipple? These answers are important to us.

 

Our 4.6L block design and internals have been around since 1991, and used in dozens of FMC applications. Our short block has worn 2V, 3V and 4V heads, SOHC and DOHCs, yet, our short block remains basically unchanged. IMHO, you can't improve perfection and the 4.6L aluminum block is as close to perfection as you can ask for in a production automobile.

 

Alas...There have been a few variants over the years, such as production engines with cast iron blocks, forged pistons, forged rods and forged cranks in factory supercharged applications, FWD applications too, as well as two additional cylinders in the V-10 configuration. However, our "tried and true" stock aluminum 4.6L block design and it's seemingly "frail" internals appears to be here to stay as FMC's entry level V-8.

 

Since 1991, our short block has been used for race engines pushing 1500 RWHP to the ground, but it took a lot of re-engineering to get there without grenading. Along the way, Ford picked up a few tips from the aftermarket, but only a few because they did it right to begin with.

 

I believe it's clear that there are limitations to the stock engine and tranny, and like "69dejavue" has posted..."Know your limitations".

[pottydr]

Mac, I'am keeping it safe, I just want to have a little kick in the butt sometimes, My car thinks its a lion @6lbs, so i will keep it that way. Rick

[BOWTIETR]

This really is another discussion, 2666, I wish you had opened a new thread. Oh well, here we go?

 

Indeed the numbers are related, my friend. Your are correct, but as the real power index, torque comes on first while HP follows the torque curve. With some mods which seem to be popular here, you can gain HP and lose torque.

 

Yes, it's true. Add a mod that has been reported to improve HP to some X degree, and you may lose torque. This means that once off the dyno and back on the street, you may be disappointed with your results in moving the car forward. It's the difference between being fast and quick, eh?

 

Evaluating overall performance strictly by RWHP (and in many cases stated here, brake/flywheel horsepower), is (IMHO) not the best way to evaluate. I suppose we like the larger numbers? Any way...When building power, watch (and build) torque. Not only at the rear wheels, but throughout the power curve. Do not be so dependent on (or, proud of?) the final numbers at the end of the dyno pull, as aluring as those number may be. Though torque may produce high horsepower numbers, the torque it takes to produce those numbers on the street is what tears up the hardware too, which is my specific point.

 

Sideline...The home stereo/audio industry went through this many, many years ago while trying to evaluate what advertised power output numbers count. The manfacturer did this to us. They started the question themselves when claims of "overall performance power" reached into the 4 and 5 digit numbers. This continues today with some products, but 12 watts of audio power times 4 speakers, is still 48 watts of power under the RMS rule. So, the "Shaker 1000" audio system does not mean that you bought 1000 watts of audio power, follow me? Finally, there came an agreement to the RMS standard (which is much like an S.A.E. adjustment to dyno numbers). Thus, is you are buying a new home stereo/audio (now called home theater) system, the bottom line is genuine audio "torque"...Actuall RMS ratings. The higher the RMS rating, the better the sound, and from less amp heat and electricity consumption.

 

It's the same scenario here. While auto mags/rags and manfacturers focus on bragging about brake/flywheel horsepower and brake torque for the higher/better numbers (read = no load), it's not the genuine/actual index of rear wheel power that consumers will see/feel on the street. Again, it's RWTQ that moves the car against the wind and against the drag of the road, not BHP, or, BTQ. Dyno RWHP is a good place to start, but it's dyno RWTQ that you should be watching most.

 

Trying to get back on topic...If a supercharger kit (as discussed here) makes 500+ RWHP with an auto-tranny in the drive line, this RWTQ has to be in that same neighborhood and it's one dangerous neighborhood to drive through with stock components in play. Backward calculate what it takes to produce 500+ RWHP through a 25% loss of drive line torque and things should begin to come clear. That neighborhood begs too much of the stock 4.6L-3V engine, and stock 5R55S auto tranny, things will break.

 

I don't mean to offend anyone, but if you own a garage/trailer SGT, I expect all will be well. But, if you intend to hammer your SGT daily, even semi-daily as a "weekend racer", keep your checkbook at your finger tips? I routinely hammer my SGT. Guess I'm not so popular here because of that...

 

Just my .02C gents, happy motoring...

 

Hey you guys worry to much its under warrenty and read the K/B info Drive it likeyou stole it and it will be ok. Also TCI has a kit or Trany that will handle 650 + HP

[BOWTIETR]

My biggest question in regards to this thread is whether the 5r55s trans will hold up to a supercharger in stock form? I've heard they are kind of weak in comparison to the 4r70w/4r75w transmissions mostly because the 3rd and 4th gear are synchronously shifted. Has anyone had any problems regarding this with a supercharger on their car and have they had it down a dragstrip under true WOT conditions?

 

They will hold up just fine, read up on S/Cs check the K/B or Whipple info, also article in Mustang and Fast fords. The K/B and Whipple make instant HP/TQ at ideal to 5500 RPM. Paxton makes it power from about3500 up if anything this type of S/C puts more stress on your engine my 2Cents worth.

[LuLu]

Well...I've been down this road before, no purpose will be served by continuing this discussion.

 

Good luck y'all.

[SGT2666]

Obviously when you push the horsepower up the likelyhood of breaking goes up right along with it. If you're budget would be totally blown if your car broke it may not be a good path to go down. The 4.6 has been very popular and so they are widely available and reasonably cheap, so if a motor breaks its not really the end of the world. Talking to the professionals who are doing these cars on a daily basis people who's reputations are really at stake, they seem to feel that somewhere under 500 RWHP with a proper tune is reasonable. Just how hard you drive your car definitely has an impact on longevity as well. The guy who thinks he's running the poop out of his stocker might find that he's able to go as fast as he wants with much less effort in a blown car and so is keeping the car at typically lower RPM's helping with engine longevity. If your going to go drag racing, well be prepared to break its going to happen its part of the program.

 

The forums are great for some types of information, but you get an aweful lot of opinion that is just BS. If you have real questions talk to the profesionals whipple, roush, Steeda, Vortech and so on. They all have phones and are quite willing to talk to you. I cruise a number of forums and I'm not seeing a rash of people having motor issues out there, and I can only assume that here in the land of more is better that many are pushing well beyond the recommended limits. Hope this makes some sense, I'm not exactly an eloquent writer

[69dejavue]

Makes me want to ask how many Whipple blowers are on the street today, on 4.6L-X engines and getting hammered hard? Stats...They can tell any story you want. Nevermind, I won't go there.

 

Anyone here at SGT/TS considering supercharging (or turbocharging for that matter) needs to brush up on the history of the 4.6L-3V used in our base Mustang GT application.

 

The truth is that at or above 500 RWHP, the stock bottom end is "twitchy" to say the least. What you can get away with on one stout engine will window the block of the next engine off the production line. Maybe no one here has yet to suffer a catastrophic failure (makes me wonder if they would 'fess up to begin with), but we remain a small and somewhat "closed" community because it's all about a Shelby. Thus, among us Shelby owners, Whipple's claim is most likely a true statement. Just give it all some time?

 

Interesting discovery...I went back to my FRP catalogues through 2003, only to learn that just a few years ago, there was no Whipple blower kit of any sort offered for FMC products at all.

 

Back then, FRP offered a Vortech SL trim kit pushing 6 PSI for the 5.0L pushrod engine. FRP also offered an Eaton 112 CID (largest CID blower Eaton makes) based kit (again @ 6 PSI) for the F-150+ fans with a modular SOHC engine, as well as offering a Jackson Racing kit employing the Eaton "Gen III" 45 CID blower for the Focus ZX3 2.0L Zetech 4. Likewise, same offerings in 2004's catalogue.

 

Whipple appeared in 2005 as an upgrade to 2003-04 Mustang GTs with the 4.6L-2V engine. Again, (IMHO) with a conservative boost of 6 PSI, and with a strong disclaimer of "installation of this kit will void your new car factory warranty". In 2006 and 2007, same offerings. Same blowers with the same boost, for the same engines, and with the same cautions. 2006 and 2007 were lame IMHO, and just adding a polished appearance option.

 

In the 2008 FRP catalogue, things from FRP changed, adding upgrades for the stock GT 500 factory supercharged application, as well as adding the option of intercooling (a must have IMHO). However, boost offered was reduced to 5 PSI...Interesting? I think so...

My point is...Step out into the real world and you will find broken 4.6L engines everywhere, and only because owners pushed the power limits by increasing boost. Vortech has been selling blower kits for the 4.6L engine for over 11 years and there are thousands of Vortech blowers in the wild. How long (rather, how many?) have Whipple blowers been in the wild?

 

Honestly, car for car (at the race track mind you), I've seen noticed that Kenne Bell blowers are "inching up" on the Vortect/Paxton kits present there for years. I have yet to see one Whipple blower face to snout.

 

This is "market presence", and IMHO, Whipple doesn't have a lot of "seat time" in the real world. Again, this fortifies Whipple's claim, but peel back a layer or two? How long has Whipple been in the market? How much field testing has filtered back to Whipple? These answers are important to us.

 

Our 4.6L block design and internals have been around since 1991, and used in dozens of FMC applications. Our short block has worn 2V, 3V and 4V heads, SOHC and DOHCs, yet, our short block remains basically unchanged. IMHO, you can't improve perfection and the 4.6L aluminum block is as close to perfection as you can ask for in a production automobile.

 

Alas...There have been a few variants over the years, such as production engines with cast iron blocks, forged pistons, forged rods and forged cranks in factory supercharged applications, FWD applications too, as well as two additional cylinders in the V-10 configuration. However, our "tried and true" stock aluminum 4.6L block design and it's seemingly "frail" internals appears to be here to stay as FMC's entry level V-8.

 

Since 1991, our short block has been used for race engines pushing 1500 RWHP to the ground, but it took a lot of re-engineering to get there without grenading. Along the way, Ford picked up a few tips from the aftermarket, but only a few because they did it right to begin with.

 

I believe it's clear that there are limitations to the stock engine and tranny, and like "69dejavue" has posted..."Know your limitations".

 

LuLu, I think it is interesting what you noted about the 5 psi boost for the factory GT 500 motor and that is a motor with forged internals as opposed to our powdered rods and cast crank, etc. Like I said, our SGTs have the same internals as Grandma's Crown Vic. And like 2666 stated, if you push it hard enough, often enough it will break. I am sure a SC with 5-6 pounds of boost used from a rolling start occasionaly would not be a problem. More of a show car. But if you drag race enough, well like the old Fram commercial, pay me now or pay me later. I do not have a SC at this time. Much of my statements is based on what I have read and from building small block Fords and Triumph Spitfires almost 40 years ago. You build em' because you broke em'. And you replace what you broke with a stronger piece. Then the next weakest link in the chain breaks and you build it again. Constantly fortifying the engine. Or you build it right the first time. Good Luck to all whatever they choose. I have not rebuilt engines or raced since 1972. There obviously have been a lot of changes since.