PSI Screw Blowers

What is the difference between the models ?
200H
B
C
D

Do they all look the same on the outside ?

Are the rotors all the same ?

Case bottom opening different ?

Front bearing plate different ?

Thanks

 

the difference between a "D" and a "C" measure the female or driven rotor lobe thickness, there are small variation based on application and date of manufacture or customers specific needs but on average a "C" will measure .483-.485 a "D" will measure .594-.596 both blowers have a open port in the housing between the front shaft/bearing supports.

 

Thank You, I have seen the "open port " between the bearing hubs. Do you know if the "B" model has that open area ?

 

B rotor is for gas. Used on boats. There are old threads here that answer these questions.

 

Mike, do you have the same figures for the B PSI screw? Thanks in advance--

 

Thank You very much for the help !

 

The B blower has the same rotors as the D but the case is shorter and the opening in front of the rotors does not extend down past the
rotor shafts.The 200 has smaller dia. rotors I believe,and no vertical braces beside the mounting holes at the base.
-Dale

 

We have 3 model's, & will offer up assistance if we can.

We have a C rotor, aka 210
Also a 206B , billet rotors, yes, as stated, for gasoline/ hence offshore boat racing on race gas, as its common knowledge i hear that the laminated rotors dont like gas,

but alcohol, prop, & nitro, although (slightly debated, as use of say 90% nitro) a screw, sense it truely compresses its air/fuel mixture, but norm says amato tested the screw on nitro, amongst others, & its no problem @ any amount of dynomite juice im told.
Some, or at least 1 Engineer who wrked on developement w norm & Niver, on the other hand, didnt like the idea of compressing the juice between the rotors.

(btw, the 206b, or aka, boat D rotor, will NOT HAVE a burst panel built into rear cover,
like full tilt buggie 200H, D & C, all built w/ laminated rotors.

We have a 200H model as well,
& it does in fact have does have a laminated rotor in it,
(hence the H for high speed) & the 200H also has the burst panel in rrar cover.

I thk norm built a 200B, which again is billet rotor, small disp, like 38x cu in, for gasoline.

That lil 200H kicks butt, btw, for its size. Its combo of being a screw, laminated lite rotor, & decreased hp to rotate, really makes her a banger for her size.

I guess we are saying that, besides askin Norm, which is best, , we may be able to answer some simple ??s about them
But we dont have a mag case tad D to provide u any insites w.

The 206B(D size billlet rotor & the 200H are both, as stated earlier, are like 1.5" Shorter, by mrmory, not fact @ moment, and both use Alum Cases vs
magnesium cases like a D NHRA version, & the C, which is also Mag case obviously.

Im far far from being any kinda knowledge base on these, just saying we hav a few models if u got a ?? that, visually, we can verify an answer.

If u need specific details design,
& can refer to a model ur wanting to work w/, if thats a possibility?
Vs every model, that helps us as some are bolted on intakes.

or yes, smart thing is to call norm if u can get him or Andy
Regards

Oh, my understanding , & im sure i will be corrected on this if wrong, and all other accounts as well , w politeness of coarse,
is that the #s are a referance to diam. In millimeters for largest spec on rotor diameter...??
Hence 200 = 200mm in a B or an H
D=206 mm ,
206 models were made in a B, & now only a D to my knowing as the true D's are (laminated & longer by 1.5" & burst panel in tear cover, are most of the basic diff ive seen.

& lastly, the "980 Knocker", the C rotor, largest psi to date.
C= 210mm , no B model C rotor im aware of, not yet.

I thk i might have some really early drawings, 80s, somewhere of the early rotors.
Folk art now, and no real value but covering up holes in drywall.
Good hunting

 

If anyone has a billet cover D rotor, can be the first gen , block letter "PSI" LOGO version , or later,( may consider a nice mag frt cover thou,)
The billet frt blk letter logo's were buult/sold from about '06 to '09, we are looking to add 1 more to the ' museum' to pay hommage to Norm, ofcoarse.

Snouts, & hats included or not are ok, but not a necessary.

Thx to Lil Jerry as well as Norm, as he built nearly all the tooling, by Norms designs, for decades,
He even cut tip strip grooves on manual bridgeport.
him & Norm were one Awesome team together.