Alternative Screw Blowers

Over the past few years there has been a lot of talk of alternative screw blowers coming from various manufacturers. For example DMPE, SSI, Whipple, and possibly others. Anyone one heard anything more on this topic lately?........

 

I was at ssi shop a week ago an there still working on the screw blower. There making rotors right now look pretty sweet. Not sure about time frame thou.

 

Who needs new technology just put an a980 whipple from 1999 on a 4.500 stroke veney headed motor and run low 3.80s to mid 3.70s in a 2400 lb pro mod !!!!

 

SSI had one at PRI 2017 I think it was. Said it was ready to go but they were arguing with sfi about the cert process. Something like sfi wanted to spin the SSI higher than the PSI is what I remember hearing.

 

SSI was doing a D rotor blower looks promising for the Alky guys but no C blower. I think it will be a long time before a new one ever comes out jmho

 

I believe when they sent out the rotors to be spin tested by the testing agency the machine stalled before the 23,000 rpm was reached. This raised some eyebrows about the testing process and existing products.

 

I "think" that the PSI rotors have to survive a doomsday box up to about 30,000 rpm for about 15 seconds, and pass a post inspection. Procedure is here http://www.sfifoundation.com/wp-content/pdfs/specs/Spec_34.1_011317.pdf. Not sure if this is the most current version or not?

I notice on the back of my C there is a sticker that says "If this unit exceeds 26,400 shaft speed, it must be returned to the manufacturer". Does anyone really do this?.........

If the SSI rotors stalled out the test machine at 23,000 rpm, then I'd have some real concerns about those rotors swelling/mating/failing. Does anyone know if those rotors were solid, or hollow segmented?

 

I remember the story now. Pretty sure SSI has a blower dyno. I'm thinking they know exactly how much power it takes to spin theirs vs a PSI and whether or not the test machine should stall out.

 

I was told by psi that they've spun them to 40k for 30 minutes at a time.