Dewey

iTrader: (1)

What is the better supercharger for a fully forged crate motor: a twin-screw, or roots? I know that the twin screw costs a little more, but is it worth it?

ScorpionT

If you an afford it, twin screw is the way to go.

stevensLS1

iTrader: (2)

Yeah twin screw is the way to go.
Just look at the 03/04 cobra's.

FastKat

iTrader: (10)

Even against the Eaton TVS 2.3? I know the smaller MP112 is nowhere near the Kenne Bell units, but how does the TVS stack up?

Dewey

iTrader: (1)

appreciate the advice guys. how much of a difference is there in price?

deuce_454

the eaton isnt a traditional roots.. its a screw compressor, or a multilobe, high helix roots at best.. but i think they call it a roots to avoit patent infringement ... (M122 left, TVS right)


and to answer the question in the post: "What is the better supercharger for a fully forged crate motor: a twin-screw, or roots? "

the engine doesnt care it responds to boost, charge air temps, and parasitic load from the supercharger... the higher efficiency the blower the the colder the charge.. hence more atainable boost on a given fuel.. also the parasitic drag fo a roots is higher... and the charge is delivered in a pused manner.. so again more drag and less atainable boost before detonation...

if you can afford an intercooled screw type blower it will be a better setup if you are shooting for maximum HP.. if you arent pushing the envelope... then why get somthing expensive, that soomthing affordable can solve???

turbos have other pros and cons... and are supperior in some ways and perhape not as great in other compared to a positive displacement supercharger.. so do centrifugal superchargers...

find out what you want from the engine and stay true to it when you decide on what parts to get.. dont deviate from it once you start building.. and for gods sake, talk to a reputable shop when you have the money to spend

pwrtrip75

iTrader: (8)

Maybe a dumb question but....isnt a roots blower just another word for a screw compressor?

bigturboz28

Twin Screw ALL THE WAY! You get the benefits of a positive displacement pump with WAY more efficiency. A roots pump simply moves air, the twin screw moves air and actually compresses it in the lobes so that for the same flow and pressure you get a colder charge while using less hp from the crank to turn it.

DeltaT

iTrader: (5)

The Eaton TVS is NOT a twinscrew. It has no internal compression at all. It is simply the most modern Roots with a hi-helix twist to the identical rotors. A twinscrew has non-identical rotors that turn at different rpms. The KB uses a 4-lobe male rotor and a 6-lobe female, and Whipple uses a 3-lobe male and 5-lobe female.

Jim

FastKat

iTrader: (10)

I don't mean to beat this to death, but are you saying the TVS is more of a twin screw than a roots supercharger? Is there a thread on this somewhere?

I would love to get more information comparing, say, a Kenne Bell and a TVS?

Z06PSI

iTrader: (33)

That is like asking if you wanna go fast or not. Twin Screw.

DeltaT

iTrader: (5)

See my reply right above yours. The TVS is not a twinscrew. His statement is bogus.

Jim

Dewey

iTrader: (1)

ok then, what is the best twin screw supercharger?

ScorpionT

Lysholm is the best, but Whipple is easier to source.

DeltaT

iTrader: (5)

Whipple has a kit for your truck:



And it looks like you'd get about 500ft/lb of torque from that 327:



Link at: http://www.whipplesuperchargers.com/...sp?ProdID=1136

Jim

hellbents10

iTrader: (10)

I agree on the Screw for big power but as far as truck "kits" are concerned you would be better off with a magnuson TVS system.

DeltaT

iTrader: (5)

Why? The twinscrew does everything the Roots does, but better. Is it a cost thing?

Jim

deuce_454

im saying that its not a traditional roots compressor with straight vane rotors that deliver boost in a very pulsed manner... the high helix roots will deliver boost in a simmilar manner to the twinscrew.. the difference is that the roots compresses in the plenum and not internally... not sure how much teh engine cares about that though

DeltaT

iTrader: (5)

Once the airstream goes through an under-blower intercooler, the pulsing is pretty much gone either way.

The Roots delivers boost by pumping more air into the plenum than the motor can handle, where the twinscrew does that as well, plus adds an internal compression cycle that makes it more efficient and able to maintain high levels of boost higher in the rpm range.

If cost is not the object, then the twinscrew will deliver more boost (approx 1.35 times more) from the same sized blower and add less heat than the Roots. A win-win.

Jim

hellbents10

iTrader: (10)

I am only speaking as how the whole "kit" works, the whipple kits I have seen are not even intercooled. I would take a intercooled roots setup over non-intercooled screw. It would be cool if the made some nice intercooled screw kits for the trucks. I think you would see a lot of the truck guys switching over when the seen the power they could be making over what they currently have.