Sorry if this was posted before, but I saw in the newest issue of C&D that Comptech is working on implementation of a positive displacement SC (I think it said Whipple) to replace the centrifugal blower (Paxton) unit. The blurb cited a 'lack of low end torque' with the current unit, or something to that effect.

There has been a lot of controversy over turbo vs. centrifugal SC vs. pos disp. SC on all the car nut boards. I'm a little unsettled on what is best, but I think that a positive displacement SC like an Eaton (modified Roots-type) or a Whipple would be an awesome match for the s2k's ferocious top end, by filling out that torque void under 6k rpm, despite a slightly lower efficiency over turbos or centrifugal blowers.

I'm not sure if people are having differential/tranny/clutch/driveshaft problems with the current blower from Comptech, but I bet a positive displacement blower would cause even more problems, since the s2k was not engineered to handle huge twisting force, especially at low rpms.

Comments?

I'm planning on an Eaton unit for my M3 once Downing Atlanta finishes their R&D on it, rather than buying a cheaper centrifugal unit such as a Vortech or Powerdyne (similar to the Paxton).



[Edited by frayed on 04-16-2001 at 09:01 AM]

 

Ive been holding off on a supercharger till bugs get worked out, but also would prefer the eaton style.

I will however re-work the engine before adding any blower.

Thanks for the good news!

 

We never said anything about redesigning the system.

 

Whoops, got the C&D blurb mixed up with some non-related articles. The blurb states "After trying and failing to boost the S2000's low-end torque via a belt-driven centrifugal supercharger, Comptech went for maximum power. The company claims its $4,895 supercharger kit adds 100 horses, thanks to six pounds of boost."

My bad.

In any event, as my 11 year old nephew says, "Duh." What would you expect from a centrifugal supercharger, which, by their design, will not make full boost till redline?

Anyone know why they didn't go with a positive displacement blower? Perhaps they experimented with this?

 

I was thinking about this on the way home last night as well. Perhaps Endyne(www.theoldone) could come up with a version for the S2000.


-shing

 

ARGGGHHH anyway I think High rpm and compression were things to get around besides the ECU.

Id still like the uddah kind.

 

A respected forced induction guy, Corky Bell, of Bell Engineering tried making a go of a positive displacement supercharger for the E36 M3. It didn't work for various reasons, detailed here:

http://www.bellengineering.net/BMWM3Turbo.html

Corky Bell is an author on the subject, and is published by Bentley:

http://www.bentleypublishers.com/author.ht...?who=Corky_Bell

The relevance here is that perhaps a positive displacement blower won't work on the s2k satisfactorily.

Like the s2k, there are only centrifugal blowers available for the M3 (although a german company called hiop is apparantly shipping Lysolhm-type (sp?) blowers as I type this).

So, if the M3 aftermarket can shed any light on the s2k aftermarket, perhaps your best bet for stump pulling grunt is a turbo.