Date:         Mon, 3 Jan 2005 01:05:20 +1300
Reply-To:     Andrew Grebneff <andrew.grebneff@STONEBOW.OTAGO.AC.NZ>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Andrew Grebneff <andrew.grebneff@STONEBOW.OTAGO.AC.NZ>
Subject:      Anyone gots a spare screw-type supercharger?
Comments: cc: SVXVanagon <svxvanagon@yahoogroups.com>
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I still plan to put a 2.2 3C-T turbodiesel into my Corolla. But I
want a Lysholm (screw-type) charger; I don't want all the
disadvantages of turbos and other superchgargers.

Lysholms (patent owned by Autorotor, licensed to Sprintex & Whipple
and soon others) are positive-displacement, compact and have no
blowby, are not rpm-dependent and do not produce waste heat hence do
not need an intercooler... and as a result do not need a huge exhaust
to dump heat so as not to dump valves or precombustion chambers.

Roots, the only other type of positive-displacement, look outwardly
like a Lysholm but are furnace-blowers designed in the 1850s (!) and
are extremely inefficient and create a large heat buildup.

Paxtons are belt-driven turbos and despite the numerous false claims
on the Paxton website, have all the failings of exhaust-driven
turbosuperchargers, but are worse for rpm-dependence (fixed rotation
rate), though they produce a bit less heat.

Turbos are too rpm-dependent and produce prodigious heat; they also
need a complex, clumsy, expensive and HOT exhaust system which
interferes with maintenance/repair around the engine bay.

I am fitting a Whipple to my SVX engine. With no other modifications
than NISMO Nissan injectors, there should be perhaps 350-400hp
produced... though I think more should be possible with no
reliability issues. The stock EG33 engine has forged rods & pistons...

Anyone know of a suitable Lysholm for sale privately?
--
Andrew Grebneff
Dunedin
New Zealand
Fossil preparator
<andrew.grebneff@stonebow.otago.ac.nz>
Seashell, Macintosh, VW/Toyota van nut