Anybody here ever run a dry( no fuel) roots blower set up?
I know most aftermarket blowers have soft strips that contact the case. I would think running a stripped blower without fuel would be detrimental to the strips.
Looking at running the fuel into the manifold after the blower. Thinking maybe a fresh Detroit diesel blower without strips would be the way to go in this configuration.
Any thoughts???

Most moderns cars with blowers inject the fuel into the port after the blower don't they? Call one of the blower shops.

Even with injection into the intake they still put some in the top to help cool the rotors.Might even keep intake air cooler.
I still use carbs,,SV1s at that!

Those aren’t roots blowers, and have oil lines for cooling.

The Eaton 2650 is considered a roots, no?
The rotors are coated, but no tip seal.

Perhaps improved tolerances allow adequate sealing with no physical seal

No roots. That’s actually a screw compressor.

I’m trying to do something a little goofy here. Some of you may be familiar with the Potvin blower set up. It is a direct link front mount blower drive that was used in the early salt flat and drag cars. The blower mounts in front of the engine, like where the radiator would go. I have an early hemi that I want to do this set up on.
Just wondering about blower temp/ life without fuel cooling the blower.

I have teflon strips in my roots.I never restripped as I an not a competitor looking for every single HP.Top fuel and alcohol teams restripe after every run or 2.Once they establish their clearance it never changes.

AFAIK Teflon can run pretty tight dry.
That Eaton model is a Roots, and simply moves air into the manifold. If the engine's normally aspirated intake volume (CFM) is smaller than the blower discharge volume it develops compression in the manifold. If the blower volume is less than the engine's, there will be intake vacuum and no boost at all.
How to tell: the left and right rotors are identical, and have continuous cross-section along the entire length.

The more complex Sprintex, Autorotor, Kennebell, IHI for Mazda, PSI, Whipple, &c. have asymmetrical rotors with different numbers of lobes (3 & 5, etc.) which change cross sectional area as they approach the discharge port.






More information on my site here (look for "twin screw"): http://victorylibrary.com/mopar/blower/blower-choices3.htm

Ok got on the roots /screw deal. i guess in my mind a high helix roots like the one shown by Outlawd is just moving air as described by Poly. Just because it is being screwed to the rear does not make it a screw compressor.
Anyway, I guess I will just call a blower company as suggested, and ask about doing what I want to do here. I have an internal struggle with this. On one hand, seems to me that the blower rotors may need more clearance in this application with no liquid for cooling. On the other hand, I know that more clearance creates heat.

If I remember correctly all the GM superchargers were mounted on the exhaust side of the engine-wouldn't have any fuel cooling there

They where set up to blow the exhaust out of the two stroke diesel motors, not force air into the cylinders
OP, the blowers heat up, all of them, when they compress air
The more pressure into the motor and the faster you turn the blower the hotter the manifold inlet temps get without a intercooler
Another thing to consider is on a Roots type motor mounted super charger the motor heat rises and will be conducted into the inlet manifold as well as the blower case from the heads and intake manifold

In the diesel application, they run dry. Only intake air runs through them. But in a diesel application they are there to make sure air is only moving in one direction, like a reed valve. They also assist blowing out the spent exhaust gasses. There is no compressing or boost created by the blower in the original application, so the blower assembly doesn’t get hot.

Important difference: all Roots blowers move air in the space between the rotor lobes and the case wall, nothing passes between the rotors (which almost completely interlock).
A twin screw type compresses air between the rotor lobes. The lobes never completely fill the opposite empty (mirror image) spaces. The inter-lobe volume is greatest at the intake port and gradually shrinks (lobes fill more of the space) until released in the manifold.

w/r/t screwed to the rear
All helixed rotors move the air forward, look how small the Eaton discharge port is (compared to the full length G.M.C. etc. window).
"Better" was invented 27 years ago, and no one caught on...