SC vs Turbo??
Superchargers are better for a heavy truck IMHO. The torque you get from a stop in those lower RPM's get these hogs moving
and lets face it, you will get more satisfaction with everyday use from a supercharger than a turbo
and lets face it, you will get more satisfaction with everyday use from a supercharger than a turbo
a correctly put together turbo system will come into boost at lower rpm levels. i have seen them perform on 3/4 ton trucks that pull trailers many times. as well as being racers. thebackpressure that you speak of is not enough to even worry about. as the heat expanding in the exhaust as well as little backpressure spin the turbo. the turbo will always outperform the supercharger once the rpm,s raise to the correct rpm,s for your set up. a supercharger kit is the best one for complete boltin with no mods to exhaust.and i have seen the log type manifolds perform very well. the s/c will go into boost just off idle. the turbo kits will come into boost around 2000 rpm,s if spec,ed right. the sts kits are great.
a correctly put together turbo system will come into boost at lower rpm levels. i have seen them perform on 3/4 ton trucks that pull trailers many times. as well as being racers. thebackpressure that you speak of is not enough to even worry about. as the heat expanding in the exhaust as well as little backpressure spin the turbo. the turbo will always outperform the supercharger once the rpm,s raise to the correct rpm,s for your set up. a supercharger kit is the best one for complete boltin with no mods to exhaust.and i have seen the log type manifolds perform very well. the s/c will go into boost just off idle. the turbo kits will come into boost around 2000 rpm,s if spec,ed right. the sts kits are great.
Last edited by anaheim_drew; May 4, 2008 at 09:00 PM.
We're getting to the point of arguing over how many angels can dance on the head of a pin...Whichever route you choose, there's the potential to make way more power than anyone needs for the street.
Is there really any "bad" forced induction setup?
Do we know many people who hate their setup?
Is there really any "bad" forced induction setup?

Do we know many people who hate their setup?
i know before its said....engine life is very dependant upon a good tune with a turbo or s/c...i keep jumping the fence and trying to figure what i want....and i keep coming back to turbo (sts), the ford racing whipple is a close second.
the fact that i see is over a given psi the turbo will make more power....
5psi with a turbo will give 500hp at crank.....5psi with sc is 450 at crank....to get the same 500hp at crank with sc one would about 7psi with a sc....it just seems to me that less psi for the same power mean the whole bottom end doesnt come out of it....
so if 7 psi is ok for a sc...then 7 psi is ok for the turbo....with the execption of more power on the turbo....
the fact that i see is over a given psi the turbo will make more power....
5psi with a turbo will give 500hp at crank.....5psi with sc is 450 at crank....to get the same 500hp at crank with sc one would about 7psi with a sc....it just seems to me that less psi for the same power mean the whole bottom end doesnt come out of it....
so if 7 psi is ok for a sc...then 7 psi is ok for the turbo....with the execption of more power on the turbo....
dont base whether your gonna blown your bottom end up on how many psi its pushin. obviously to many can be bad but you have to look at how much air its moving. which is why that 5psi on the turbo is making more than 5 psi on the s/c. its moving more air.
5psi vs 5psi is the same amount of air movement. A turbo isnt pulling a load off the engine, which is why it makes more power. your not going to "blow" the bottome end out with a lot of boost. A crappy tune will "blow" your bottom end apart. A headgasket will fail before you throw a rod with a good tune.
Ok Gentlemen let me put this to rest once and for all.
Sorry I couldn't resist.
The reason that a turbo makes more power at 7 psi is that it takes less Hp to drive the Turbo. So lets say that 7 psi through Blown's engine produces 450 hp. It takes 50 hp to make the 450 with a blower so that nets 400 to the crank. It takes only 15 hp to drive the turbo so that nets 435 to the crank. That assumes that you are flowing the same amount of air and adding the same amount of fuel for both examples. You can play around with blower size and you can also play around with turbo sizing bit to keep it fair use the same cfm of air for both examples.
Regards
Jean Marc Chartier
PS. my next mod is a turbo.
Sorry I couldn't resist.The reason that a turbo makes more power at 7 psi is that it takes less Hp to drive the Turbo. So lets say that 7 psi through Blown's engine produces 450 hp. It takes 50 hp to make the 450 with a blower so that nets 400 to the crank. It takes only 15 hp to drive the turbo so that nets 435 to the crank. That assumes that you are flowing the same amount of air and adding the same amount of fuel for both examples. You can play around with blower size and you can also play around with turbo sizing bit to keep it fair use the same cfm of air for both examples.
Regards
Jean Marc Chartier
PS. my next mod is a turbo.
not to say i knew that, but it was a statement not a question....i was hoping that someone could sell me 100% of one over the other...there are advantages i see of the sc is the neat compact setup under hood, intant boost instead of a 1-2 sec delay (most turbos at 5 psi hit max boost of 5 psi in 2500 rpms or less, how long does it take from idle at 800 rpms to 2500 rpms...not long) and the evil sound of a sc...
i have tried to convince myself that the whipple is the setup to go with but sts seems like a slick setup.
does anyone have the whipple for the current 5.4 3v...not a 4.6 or older 2v???? i have tried to see what all comes in the setup, it says complete but no plugs are mentioned...are they not needed??? is the plug intervals 20k miles or more??? what is the base psi with the ford racing whipple, straight out of the box....???? is the intercooler work well enough or is a bigger one needed??? i read the oiling system is self contained....how is it serviced and at what mile mark is it serviced???
any additions or answers to questions would be a great addition to this thread
i have tried to convince myself that the whipple is the setup to go with but sts seems like a slick setup.
does anyone have the whipple for the current 5.4 3v...not a 4.6 or older 2v???? i have tried to see what all comes in the setup, it says complete but no plugs are mentioned...are they not needed??? is the plug intervals 20k miles or more??? what is the base psi with the ford racing whipple, straight out of the box....???? is the intercooler work well enough or is a bigger one needed??? i read the oiling system is self contained....how is it serviced and at what mile mark is it serviced???
any additions or answers to questions would be a great addition to this thread
Ya'll need to get the whole "turbo lag" idea out of your heads.
Let's address a few issues.
A properly designed and spec'd turbo kit using a quality turbo will have virtually no discernible lag. Very few here are going to use a max effort 76mm or PT88 turbo which are about the largest that can reasonably fit on these trucks. Even with those monsters the lag is small on a built and cammed 5.4L.
Positive displacement superchargers DO NOT make instant boost any more so than a centrifugal compressor. The reach PEAK boost sooner, it sure as hell isn't instant.
Dollar for dollar, psi for psi, a turbo kit will make more power. Unless you get a cut rate deal on a new supercharger kit or a used one you can't beat a turbo system in terms of total gains for money spent. Yes, they usually cost more up front but after you've spent money on a pulley and good headers to match the gains of a turbo kit you've already spent the "savings".
Turbocharger compressor technology is also much more developed than those of Roots, Twin-Screw, and most centrifugal superchargers. Even the most efficient superchargers aren't as good as current turbochargers.
Let's address a few issues.
A properly designed and spec'd turbo kit using a quality turbo will have virtually no discernible lag. Very few here are going to use a max effort 76mm or PT88 turbo which are about the largest that can reasonably fit on these trucks. Even with those monsters the lag is small on a built and cammed 5.4L.
Positive displacement superchargers DO NOT make instant boost any more so than a centrifugal compressor. The reach PEAK boost sooner, it sure as hell isn't instant.
Dollar for dollar, psi for psi, a turbo kit will make more power. Unless you get a cut rate deal on a new supercharger kit or a used one you can't beat a turbo system in terms of total gains for money spent. Yes, they usually cost more up front but after you've spent money on a pulley and good headers to match the gains of a turbo kit you've already spent the "savings".
Turbocharger compressor technology is also much more developed than those of Roots, Twin-Screw, and most centrifugal superchargers. Even the most efficient superchargers aren't as good as current turbochargers.
on STS' website the 04 f150 with the kit made 348rwhp and 450rwtq running 7lbs. The kit also includes 39lb injectors which I didn't know. They didn't have a price advertised though you have to call
Dollar for dollar, psi for psi, a turbo kit will make more power. Unless you get a cut rate deal on a new supercharger kit or a used one you can't beat a turbo system in terms of total gains for money spent. Yes, they usually cost more up front but after you've spent money on a pulley and good headers to match the gains of a turbo kit you've already spent the "savings".
$4500-$5500 for any blower on the market for our 04+ F150 with pulley and headers(not needed) since all are making more power than the turbo kit and for less..
Last edited by anaheim_drew; May 20, 2008 at 05:03 AM.



