Superchargers. centrifugal vs. twin screw...
whenever i can afford one of the newer GT's my first mod will be a supercharger. i want to know the pro's and con's from the guys who have these systems installed. any help would be nice, don't be afraid to get technical i think i will understand what you say.
Some of the reasons I went with the roots style SC. The oil system is self contained and does not recycle the engine oil. No reason to drill holes in the oil pan. The torque is almost off idle instead of starting at higher RPM. I think the packaging of the Sc on the motor is better. The weight is on top instead of being hung off the front. There are newer centrificals that address some of these issues, but they limit your choices. Ga
I am personally drawn to the twin-screw supercharger, primarily the Kenne Bell one. It really is an amazing kit but pricey. If i wanted to save a few bucks, the Vortech blower is a much more affordable way to gain some big power:bigthumbsup
Centrifugals look gay. :hihi:
i don't want a quiet S/C. does anybody know who has the loudest one on the market?
Your Techco Is a Twinscrew not a roots.:bigthumbsup
Some info I found
The roots supercharger features two counter-rotating lobes that trap air from the intake side of the supercharger (normally at the back of the supercharger), move it around the outside casing of the lobes, and out the bottom of the supercharger through an outlet / discharge port. Like the twin screw supercharger, the roots is a "positive displacement" aka "fixed displacement" supercharger, meaning that it moves a fixed volume of air per rotation. Notwithstanding minor amounts of air-leak at low rpms, the roots supercharger cannot flow backwards like a centrifugal supercharger, and is thus nearly as efficient in its ability to pump air at low rpms as it is at high rpms. What this means is that roots superchargers are very capable of making large amounts of boost even when rpms are very low. This makes for great low-end and midrange power, and also makes them great for trucks and towing vehicles. The roots is also self lubricated, and is the simplest of the supercharger designs, meaning it is reasonably priced and very reliable.
The twin screw supercharger at first glance appears to look similar to a roots supercharger both inside and out. The two technologies are indeed similar, however there are significant differences. At the heart of the twin-screw supercharger are two rotors , or "screws" that rotate towards each other. The rotors mesh together and draw air from the back of the supercharger. The twisting rotors move the air to the front of the supercharger, while compressing the air before discharging through a port at or near the front of the supercharger
Although the centrifugal supercharger is founded on a technology much newer than either the roots or the twin screw, it was the first supercharger to be successfully applied to automotive applications. Unlike the roots, the centrifugal supercharger is NOT a positive displacement / fixed displacement supercharger because it does not move a fixed volume of air per revolution. The centrifugal supercharger essentially operates like a fan propeller / impeller, sucking air into the center of the supercharger and pushing it to the outside of the rapidly spinning (40,000 + rpm) impeller blades. The air naturally travels to the outside of the blades because of its centrifugal force created by its rotating inertia. At the outside of the blades, a "scroll" is waiting to catch the air molecules. Just before entering the scroll, the air molecules are forced to travel through a venturi, which creates the internal compression. As the air travels around the scroll, the diameter of the scroll increases, which slows the velocity of the air, but further increases its pressure.
I had a Powerdyne centrifugal supercharger on my '93 Cobra. It is a dry-bearing system, so no oil lines or drilling. Pushed 9lbs of boost without inter- or after-cooling. Totally loved it. Ran 12.20's on cheater slicks with factory 3.08 rear gears (we didn't have drag radials back then...). I don't know if they are still out there, or if they are available for the 4.6's, but I do know other centri- blowers are now available with self-contained lubricating systems.
These days, I have an intercooled (technically I guess it's aftercooled) HO Whipple kit on my '06 GT. Totally love this one too.
The biggest difference between the centrifugals and positive displacement blowers, speaking generally, and refering to street cars, is that the centri's build power & torque progressively as rpm's increase, whereas the positive displacement (roots, twin screw, etc.) blowers make lot's of torque almost instantly.
So I would say you should decide if your preference is instant, low-end grunt, or high-end power with high rpm's. Once you answer that question, your choice is made... Either way, you're gonna be full of giggles every time you step on the throttle!
***...take into account drivetrain (clutch, transmission, driveshaft, rear end, ...), suspension (shocks, uca's, lca, relocation brackets, ...),
gauges, fuel system upgrades, ... , tuning, pulley, tensioner,possibly a bottom end, ...
As long as none of that (downtime, money ) are not a surprise, you are ready to make your choice of which kind of superchargerj!! :bigthumbsup
thanks for the help guys. i'll probably get a Kenne Bell. i wasn't sure which system was better for low end touque, i want to drive on the street and have a relatively flat torque curve. i do understand what all is needed for an install like that. i plan on selling my v6 after i finish the installation so i have something to drive.
Wow, I really hate it when people refer to all positive displacement superchargers as roots style..
By the way, roots style will build more boost as rpm increases. The Edelbrock is a roots style TVS supercharger, and with the 6 psi pulley it will generate almost 8 psi at the top end. The TVS rotors are the most efficient roots style setup out there, but is just not capable of generating the same amount of boost as a twin screw given the same displacement between the two. You have to go BIG on a roots style to get over 15 psi in a 250+ cubic inch engine.
Roots Style: Eaton (GT500), Magnacharger, Edelbrock E-Force, Roush
Twin Screw: Kenne Bell, Whipple, Techco, Saleen
Centrifugal: Vortech, Paxton, Pro-Charger
I am not sure on the Pro-Charger or the MagnaCharger, but the rest all have self contained oil systems in their latest incarnation.
The Centri would be the easiest install of any of them, especially if you went the cheap non-intercooled route. The Kenne Bell is probably the most intricate install, just because you have a TON of relocation to do. I spent about 30 hours on the KB install, taking my time.
Cost wise, all of them are in the same range given the same options. It is when you add or delete options that the price changes.
For example: A Vortech V3 non-intercooled package can be had for about $3800. A Kenne Bell Stage 1 unpolished intercooled setup can be had for about $5700. A Techco, with the 8 rib belt and GT500 pump system is about $7500.
However, a Vortech H.O. (intercooled) setup is about $5600, and the basic Edelbrock package is not far off. The differences in basic intercooled kits are all within a few hundred of each other.
The Whipple is a little more expensive than other equivalent choices, and the Techco is the most expensive, but also comes with the most extras (8 rib belt, upgraded tensioner, the sale right now adds gt500 pumps for free). Kenne Bell is, pound for pound of boost, the best deal out there, because they sell direct, rather than wholesale to a third party. Cut out one middleman and prices go down. On the other hand, customer service can be lacking as they have one number that is almost always busy.
Any way you go you will probably be happy.
Which bring me to the question Klrstng. You finally get your issue resolved? I hope she is running they way she should now.:bigthumbsup
Just decided I would install my Techco myself.
So broke it down today. Really easy with Techco directions. Took about 2 hours with hand tools. Should get the blower no later than monday and I can start the rest of the install.
Apparently it takes a bit longer to get the polished version from them, then they originally thought.
one does not simply put a badassian supercharger on a unmodded stang.
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